That should be hell for stout! Nice piece of work right there, And thanks for taking the time to share with us all.
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That should be hell for stout! Nice piece of work right there, And thanks for taking the time to share with us all.
Thanks and your welcome! Back when I made a living doing machine and fab work, we built a lot of stuff for the oil patch. Everything had to be way overbuilt and I guess old habits die hard. As bad as some of the roads are around here, it's probably not a bad idea!
Man! I can't believe it's been over 2 months since I last posted anything on this thread. I've been busy and got a lot of stuff done, just not as much on the car as I wanted. That always seems to be the case though. So I'll be "binge" posting until I get caught up.
There have been a few more changes to the plan. This car seems to be evolving more than any other project I've done. It's slowing progress down and costing more, but I think I will have a better car in the end. I hope so anyhow.
I had originally planned to go with Mustang II coilovers. These are the ones that have the barrel shaped spring that fits the MII coil pocket on top and taper down to about 2 1/2" at the bottom. The problem with these is that the special springs are only available in 4 spring rates in the short MII application and only 2 of those would be anywhere near correct for the weight of this car. I decided that I would be better off modifying the upper spring pocket to take a regular coilover.
Of course, I had this little epiphany after I had already made some modifications to the upper control arm mounts. I had altered them so that the front end had some anti-dive built in and to make the caster/camber adjustments with shims. The original setup on this car had no anti-dive. It also used the original MII method of adjusting the alignment by sliding the upper arm in slots.
While I was at it, I made the upper arm mount adjustable for height. This allows the roll center of the front end to be altered as well as the camber gain. By adding or removing shims from under the upper control arm mounts, you can alter the spacing on the control arm pivot points. This isn't normally something that can be changed on most cars.
My current ball joints are Moog parts, but QA1 has some racing ball joints that will fit my control arms and are available with different length studs. This effectively alters the length of the spindle and changes the angle of the upper control arm. All these things will change the camber gain and the roll center height of the front end. Will I ever use all this adjustment? I don't know, but it will allow me to experiment and see just how altering the front end geometry will affect the handling. Who knows, I might decide to auto cross this thing one of these days. The QA1 ball joints are also very low friction and rebuildable.
I built the upper control arm mounts with the ball joint centerlines off set for about 4 1/2* of positive caster. This saves stacking a lot of shims on one end to get the caster that you want in the first place.
http://i185.photobucket.com/albums/x...pslvq5ol8d.jpg
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Some of the welding is unfinished in these shots, but you can get the idea of where I was headed. The bracket in the first pic bolts to the top and is braced by the vertical plate. The upper control arm attaches to this bracket. By putting shims under the bracket, the spacing of the control arms can be altered.
I cut out all the mounts I had built and rebuilt them to accept true coil over shocks. All the original adjustment modifications I made are still there, but I think they turned out better the second time around. Regular coilovers have a much wider selection of springs available than the MII coilovers, including some that are variable rate. I was also able to get the upper control arm mount lower by not having to maintain the MII upper spring perch. This just gives me more adjustment,but I doubt it will need to be that low. I'll be building a cross brace between the shock mounts later on.
The coilovers in the pics are not the ones I'll be using. They're an old set I had, but they do give a starting point. I'm leaning toward Viking double adjustable pieces. They are made in the USA and are adjustable for both compression and rebound.
Luckily, all these changes so far have only cost a little material, labor and time.
http://i185.photobucket.com/albums/x...psfznuxznj.jpg
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Here's a little bonus video. I needed to thin one side of the control arm bracket a little, so I used my antique shaper. These are fascinating old tools to run and can do an amazing amount of different jobs. They are slow by modern standards and considered obsolete. They are great in a home shop if you have the room. In this case I was able to use a cheap and simple hand ground tool to remove this metal instead of an expensive mill cutter.
This really has nothing to do with car building,but I thought some might enjoy seeing the old tool at work.
http://i185.photobucket.com/albums/x...pswnvlz3an.mp4
I'll be posting more updates ASAP.
Mike
I also built an adjustable steering rack mount. It adjusts both vertically as well as forward and backward by adding or removing shims. It's common for the Mustang II front end to have some bumpsteer. There are kits available that lower the outer tie rod ends and allow adjusting most or all of this out. The aftermarket kits use long studs and aircraft rod ends (heim joints) to replace the stock tie rod ends. The heims are probably plenty strong enough, but I would prefer to use parts purpose built for steering.
My setup allows the rack to be raised and accomplish the same results while retaining the stock tie rod ends. Most cars don't have room to raise the rack because of oil pan clearance issues, but this isn't an issue with the Sebring due to the engine being well behind the axle centerline. I also laid the rack back a few degrees. This is a street rod trick to give a little more clearance around the engine and straighten the steering u-joint angIe out.
The new rack mount is built for the later model Fox body Mustang rack. These have slightly narrower mounting hole spacing than the Mustang II parts, but are supposed to have better feel and ratios. The Fox power racks can use standard pressure GM pumps, too. MII racks need lower pressures and can have sensitivity problems as well as leaking issues if used with the wrong pump pressure. I have experienced that over boosted sensitivity on my 46 coupe and it isn't fun. I mocked up with a regular Fox power rack(3 turns lock to lock) of unknown origin, but I may use a faster ratio unit in the final assembly.
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I decided that the next thing to attack was the engine. I wanted to get it and the trans in before moving to the rearend.
I had said earlier that I was going to use a 383 small block, but that was actually my second choice. I was originally thinking of going with one of the newer LS type engines, but really didn't know anything about them. I was studying them, when I learned that there was going to be an issue with the LT1 T56 transmission that I already had. The model of trans I have can't be converted to LS configuration. The input shaft is not available for my gearset and synchro setup. I either had to sell the trans I had and buy another or go with a Gen 1 small block. I didn't have any luck selling the T56, so I just moved on from the LS to a small block.
Then I went on the Power Tour and it seemed that every car I looked at had an LS engine of some kind. Everything from dragged-out-of-the-weeds beaters to show cars. I really wanted to see what all the hype was about. Everyone I talked to raved about them. I decided on that trip that I would look at them again.
I bought (and read) several books, read a bunch of articles on the net and poked around on some LS forums. I consigned myself again to trying to sell the LT1 T56 so that I could buy an LS trans. I had talked with some of the vendors on the PT and was quoted prices in the $4500-$5000 range for a new trans package, but there was no way that was going to happen.
One evening I was reading an article on adapting older 4 speeds to the LS and a (somewhat dim) light bulb went on over my head!
See, if you use the right aftermarket flywheel, you can bolt a regular Gen 1 Chevy bellhousing and trans to an LS and use the regular old Chevy clutch. You wind up short one bellhousing bolt, but there are a bunch of folks running them like this.
I had already bought a special T56 bellhousing for the small block made by a guy in California named Weir. It allowed the LT1 trans to be used on any big or small block Chevy. You could use a 1 or 2 piece rear seal and any size flywheel. It came with a custom hydraulic throwout bearing that made all this possible.
I started thinking that if you could hang a regular 4 speed on an LS with the right flywheel, why couldn't I hang my LT1 trans on one using the bellhousing I had? It turns out after some measuring that it will work. It's not the ideal setup, because it actually costs more to do it this way. The Weir bellhousings are kind of rare (I found mine on EBAY)and I don't know if he even still makes them. I already had the parts so it was cheaper for me. Boy, that sounds like hard justification if I ever heard it, but where there's a will there's a way!
Soooo, I decided to go back to the LS engine I wanted to start with. The trouble was, I didn't have one.
http://i185.photobucket.com/albums/x...psy2wnahjv.jpg
The Weir bellhousing is very well made and heavy duty. It isn't rated as a scattershield, but it is a very thick casting. You could make several of the stock LT1 bellhousings with the metal in the Weir part.
http://i185.photobucket.com/albums/x...psqhx1jsxp.jpg
This is the LT1 T56 I have. It has a 2.97 1st gear and a .64 6th. It's my understanding that this is considered a close ratio unit.
Great work, nice welding, and great execution. I was thinking of going with an LS and a 4 speed too but I ran into the issue you had as well. I just decided to keep the original plan I had and quit trying to make it more difficult. It seems 5.3's can be found all over for $500-$950. I wanted to go with a 6.0 and those seem to be about double or more than the 5.3.
Thanks 40! I still have a lot to learn about the LS engines. Like you. I wanted something bigger than a 5.3. However, all the folks I've talked with say that the little engines are stronger than you would think (especially with a little tune on the ECM). The big difference seems to be that everybody says they don't make as much torque down low as a 350 SBC, but make up for it with a higher rev range than a typical stock based 350. The stock LS heads have pretty big ports compared to a typical Gen 1 350.
Everybody recommended gearing them so that you can use the revs. Just about to a man, they said to let'em rev and you'll be surprised. I did wind up with something a little bigger than a 5.3 and I'm hoping I will be surprised. I'll post that part of the story ASAP.
After searching for some time I learned that 4.8 and 5.3 truck engines are plentiful and fairly cheap, but I really wanted something bigger. The 6.0 and 6.2 engines are in demand and their price reflects that. The big engines were either high mileage and expensive or low mileage and even more expensive. The early 5.7's that I found were fairly simple and most had cable operated throttles, but all were pretty high mileage and since they came in Camaros and Corvettes, they were pretty expensive too in spite of their mileage.
Also, many of the really late model engines have displacement on demand (cylinder deactivation) and/or variable valve timing. They also have drive by wire throttle bodies. I didn't want to deal with all those things on my first LS swap.
I finally located what I thought was a pretty good engine in Arkansas, about 350 miles from my house. It's an almost new 97 5.7 Corvette engine. This was a long block replacement engine that sat for years in a guy's unfinished project before he decided to part it out. He said it had only been test fired. His project was unfinished so I tend to believe him. The engine doesn't appear to have been "cleaned up" and is too clean in hidden areas to have been run much. It came with an aftermarket wiring harness and a reprogrammed computer. I heard it run on video and he had it pulled out of the Jeep and strapped to a pallet when I got there.
Now we've all heard about the engine that "came out of my brother's/uncle's/whoever's 'Vette" and was 375 HP, even if it had a 2 barrel carb! I can say that this engine still had the factory paper bar-code tags on it and they did indeed identify it as 97 LS1. After the previous owner told me how the engine was setup when he got it leads me to believe that it really is a Corvette engine. 97 is the first year and they had a few changes made in later years, but this engine was rated at 345 HP at the crank as installed in the Corvette.
Most folks I've talked to say that with a good exhaust system and a little computer tune, it should make 30-50 more HP without turning a wrench. I know the ECM has a sticker saying that it has an "off road" tune, but that probably just means it had the after CAT O2 sensors and other pollution stuff disabled.
The previous owner swapped the Corvette's drive by wire throttle body out for a cable operated one and that's OK by me. He also swapped the water pump and harmonic balancer out for Camaro parts because of the special power steering pump he had on it. No problems there either. The shorter Corvette parts would have been nice, though.
The one thing he did that will have to be changed is that he swapped out the nice "batwing" Corvette oil pan for a truck pan. The truck pan is way too deep for my car. The shallow Corvette pan was heavily baffled to prevent oil starvation in corners. That would have worked out nice. The engine also had a set of Advance Adapters steel motor mounts, a set of "no name" stainless truck headers, a Camaro alternator and a starter.
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These are the previous owners pics. I forgot to take any when I went to pick it up.
I paid more for the engine than I wanted to, but if it truly is an "as new" engine, I got a bargain. I can tell more when I pull the oil pan to swap it.
I would like to think that I had the first Sebring to get an LS engine, but that's not the case. There are at least two others out there somewhere. I found pictures of them on another forum. Unfortunately the threads are more of a "this is my car" type thing instead of build threads. So there is not much info on what they did to get it all to work. Both cars appear to have Corvette engines or at least Corvette engine covers and accessory drives. I think both have automatics. Also, both engines appear to sit very high in the engine bay.
Time for another series of long overdue updates. I've gotten a good bit done since the last posts. I've been pretty busy, but not always on the car and not everything I've done on the car has worked out like I hoped.
When I left off I had just acquired a 5.7 LS1 and needed to get it in the car.
In the LS swapping world, there are dozens of adapter plates that allow Chevy motor mounts to be attached at various places on the block. I think the other cars I found online used some version of these plates to bolt up to the existing Sebring mounts.
When I finally got around to getting my engine and trans hung over in the chassis, I looked at going in that direction. The problem is that you wind up with a motor mount on an adapter and then that is bolted to the original adapter on the frame.
That's a lot of stuff and it looks awkward. The original Sebring mounting system made a lot of sense from a manufacturing standpoint. You made one chassis and a bunch of different motor mount adapters. You could fit just about any engine that way with minimal effort. The main drawback is that it's a bulky system that gets in the way of good exhaust.
I decided to get rid of the original mounts and build my own. I wanted to use the Corvette style mounts that would have originally came on the engine. They mount well forward on the block and would have given plenty of exhaust clearance, but they just didn't work out. The fluid filled mounts are pretty big and also have a tendency to leak nasty dark fluid out if they rupture(one of the ones I had was already leaking). I have read that they will fail if you use a lot of right foot. I tried swapping the fluid mounts out for the old Ford biscuit style mounts. Street and Performance recommends this route, but that didn't work either. They were going to interfere with the 1 x 2 lower frame braces.
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This is what the original Corvette mounts looked like.
I wound up using the steel mounts that came with the engine and the Ford biscuits. I had to fab some frame mounts. Before I could mount anything I had to get rid of the original mounts. I cut the old strut brackets off at the same time. I still need to do some grinding on the bottom of the rails, but that will have to wait until I can flip the frame over for better access.
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The frame mounts are pretty simple and I had to make a special stepped washer because the mount bolts are 7/16" while the holes in the engine mounts are 5/8". One is longer because the centerline of the engine and trans sits one inch to the passenger side. I had to move it over to clear the firewall on the driver side. I'm not worried about it because many cars have offset engines and it will just balance out the weight of my fat butt on the driver side.:LOL:
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I trimmed the Advance Adapters steel engine mounts that came with the engine and reused them.
http://i185.photobucket.com/albums/x...psibdmu2z3.jpg
The frame mounts are actually upside down in this shot. I realized that the engine was going to be way to low with them like this.
I realized pretty quick that the truck headers that came with the motor wouldn't work and even if they had, the collectors would have been right next to the driver and passenger foot wells. That would have been pretty toasty.
I found a set of LS2 Corvette manifolds and they actually fit pretty good, but I had to replace the square tube rails that snake around the engine from the trans tunnel to the top of the frame. The rails just wouldn't let the me get the engine back without hitting the manifolds. I made the rails longer and higher and solved that problem. I'll eventually brace the rails to the frame, but I'm waiting until I get the steering and exhaust done in case there is any interference.
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A few days after I got all this done, I took a short vacation to Mena, Arkansas for some motorcycle riding. That's the home town of Street and Performance.
I dropped in on their shop to pick up a straight thermostat housing, since the original angled one isn't going to work. While I was there, they took me on a tour of their operation, which is actually a manufacturing plant and full service custom rod shop. They even have their own aluminum foundry and chrome shop!
They also fab their own headers and while we were in the header shop I spied some parts that I thought might fit my car. I really wasn't planning on buying headers, but these looked too close to the right size and shape to pass up. As it turns out, they actually fit with more clearance than the iron manifolds. I actually could move the engine back some more, but I'm going to leave it as is. If I have problems with the headers, I know I can switch back to the manifolds.
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The ceramic coating should help keep underhood and footwell temps down.
Once I had the motor mounts in I moved on to the trans mount. I have lowered the engine so the original trans mount was too high.
I thought about a few different ways to build it, but in the end I decided to just make one similar to the original. It simply bolted through some reinforced areas in the floor. The floor in this car is 16 gauge steel and the doubling plates made it almost 1/8" thick.
The new 6-speed is several inches longer than the original trans so the mount fell outside the reinforced area. I didn't have any 16 gauge on hand, so I added some 1/8" plates to the new location.
I drew the new crossmember on my welding table and bent it out of some flat bar. A few holes and simple braces and it was done.
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With the engine finally in place and the driveline angle more or less set, I decided to tackle the rear suspension. I kicked around several options including a 4-link, 3-link and a torque arm. I wanted something that could be tuned for extra traction by adding anti-squat and all of these could do that. I spent a lot of time reading all the books I could find on suspension for handling. I poured over several websites dedicated to "pro-touring" also. General info was easy to find, but specific design stuff was very thin. I eventually had enough info that I thought I could come up with something that should work.
I eliminated the 4-link because as you add anti-squat, they can bind as the body tries to roll in a curve. The 3-link and torque arm both can roll without binding.
I was leaning toward the torque arm because they are fairly easy to package under the car, but the length of the arm was going to wind up being pretty short on this car. Actually 36 inches or less. When you get a TA that short, you will have very high anti-squat, but it can cause loss of traction under braking even to the point of "brake hop". In extreme cases, the rear axle can actually lift off the ground. Also, the TA has very limited tuning capability, so what you build is pretty much what you're stuck with.
This meant that the 3-link was what I was left with, but that's not really a bad thing. The 3-link can have a high anti-squat percentage and still roll without bind. The main downside to the 3-link is that they are notoriously hard to package under a passenger car. The upper link is the culprit, because it wants to intrude into the passenger compartment.
There was another option that I considered and that's a decoupled torque arm. It's a hybrid combination of the 3-link and the torque arm. A very short TA is used for high anti-squat under acceleration and the arm is set up to decouple from the chassis under braking. A sliding upper link (like a 3-link) is set up to do nothing under acceleration and come into play under braking. The upper link is arranged to give a long virtual swing arm during braking so there is no loss of traction. This suspension theoretically does everything well, but it's complicated and heavy because of all the different links that are needed. From what I could gather during my research, tuning the transition from acceleration to braking is tricky, too. It looked very interesting and I was tempted to try it, but I decided my limited knowledge might get me in trouble with this setup. So I passed on it.
No matter which suspension I used, I was going to need something locate the rearend laterally, too. The 2 most common ways are either a panhard bar or a watts link. The panhard bar is simple, but forces the rearend to move side to side slightly as the suspension travels. The bar needs to be as long as possible to keep this to a minimum. Because this car is fairly narrow, the PB was going to be short, so that option went to the bottom of the list.
I went with a Watts link. It has the advantage of only allowing the rearend to move straight up and down, but not side to side. Also, the roll center is literally a fixed pivot and can't change. It is a lot more complicated than a panhard bar, though.
I built a lot of adjustment into my setup. Probably finer than actually needed. I cut serrations into the front link mounts that allow me to move the bars in .100" steps. The serrations allow the adjustments are locked in so they can't slip. I also have 3 holes on the lower rearend mounts. The roll center can be raised or lowered by moving the watts link center rocker (propeller). The upper and lower shock mounts can be raised and lowered, so getting the ride height spot-on should be easy.
I used heavy duty rod ends on the upper and lower links. These are from Spohn Performance. I picked them because they are adjustable for tension, rebuildable, and greaseable. They're forged 4130 and should last forever. The lower links are 1.25 OD with a .120 wall. According to the 3-link spreadsheet that I found (after I started building, of course), the upper link has an 18x safety factor under acceleration and the lower links have a 26x safety factor! The calculations in this spreadsheet are supposed to be based on 1 G of acceleration (which I seriously doubt is going to happen), so I guess they're just a tad overbuilt. At least I could go drag racing without worrying about failure due to weak parts! 3-links usually aren't used for drag racing because of the single upper link.
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I've got a lot more construction pics. I'll try to get some more stuff up tomorrow night.
Vary nice wook
WOW! That's NICE!
Thanks guys. I put a lot of time and cussin' into it!:3dSMILE:
Both upper link mounts caused me a lot of trouble, but that's not uncommon. I studied the Factory Five Cobra/34 roadsters because they were the only cars that I could find that are similar to mine using a 3-link. I know someone that has a FF 34, so it was easy to get a good look at one.
FF hangs their upper axle link mount way out on the axle tube. Offsetting the upper link to the right helps to load that tire more under acceleration. Without any real design data to go on, I out started pretty much copying FF's mount on the rearend. I was well into that build when I found some fairly reliable info that recommended starting at 8-12% of track width. My car is has a narrower track than a FF car and putting it where they did would have put it well over 12% offset.:mad: Now it may still have worked fine, but I didn't want create a problem that couldn't be fixed without major surgery.
I scrapped all that I had built and started over. Because the 8.8 rear has a cast center section, I couldn't reliably weld the top link to the housing. I came up with a bolt-on link bracket.
I machined a section of the rear cover flat and made some steel spacers to go under the plate. It also bolts to a bracket welded to the axle tube. It's solid, but heavy(too heavy). When it comes off next time, it will go a serious diet. I need to do a lot of trimming and you can expect it to look pretty "swiss-cheesy" when I'm done with it.:D
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The upper frame mount had problems of it's own. The only solid thing to weld it to was the trans tunnel. The tunnel is a deep section box and is a pretty stout structure in the direction it'll be loaded, but it's thin.
I built a complicated mini-crossmember that tied into the tunnel with a large plate and stretched over to the frame rail. The cross piece had to be angle cut to match the back of the passenger compartment. There was just enough room to squeeze it in.
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I couldn't just let the link adjustment "box" just hang down with no other support. I built a gusset that ties into the bottom of the link box and the floor. The gusset falls right on the same plane and level as the floor, so any stress is fed into a large area. I'm confident that this mount will handle a lot of horsepower.
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I also add a row of nuts to the back of the link box so that I could bolt on some boxing plates after I get it adjusted. These should reinforce the slot and keep it from spreading under load.
I have enough adjustment to get close to 100% anti-squat with no roll steer, but I'll never use that much. The info I've found says that for a car that goes around corners, about 40% is all you can use. Any more and the car starts to lose rear traction if you decelerate entering a corner. Of course, that's for a race car right on the limit of traction, a street car may be able to use a little more. It's available it I want to experiment.
Here's a couple of videos. The first is the shaper working on the blanks for the sides of the link boxes. This will have a step in it for the adjustment serrations.
http://i185.photobucket.com/albums/x...pszvqapkeu.mp4
This one is the serrations being cut. It was a looooooong process.**) My wife says that machine work is like watching paint dry!
http://i185.photobucket.com/albums/x...psao7qscfu.mp4
I'll put some stuff about the Watts link up tomorrow.
Your wife is right! At least a shaper has a motion you can follow. The horizontal looks like the travel was painfully slow.
It's not as bad as it looks. That's a horizontal attachment on my Bridgeport CNC. It doesn't have full CNC capacity, but I can write simple short programs. I really didn't have to sit and stare at it the whole time. The program did all the boring repetitive stuff. I was running it with a fairly slow feed rate to protect the cutter. I only had one with that contour.
I could have mounted the watts link rocker on the rearend, but chose to mount it to the frame. If you put it on the rearend, the roll center stays the same height from the ground, but the relationship with the center of gravity changes as the suspension moves. Mounting it on the frame keeps the distance to the center of gravity constant.
The argument for frame mounting says that since the tires are loaded by weight transfer acting from the center of gravity through the roll center, frame mounting gives more consistent tire loading. This made sense to me, but lots of folks mount it on the rearend with apparently good results.
I built the rocker to take tapered bearings like a wheel. Actually, the bearings are 1" trailer bearings. I used a kit that serviced one trailer wheel. I had to make a short spindle. If I had mounted it to the rearend, I would have carved the rocker out of aluminum to save weight. Since I hung it off the frame, I used steel.
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The frame that holds the watts link had to bolt in. If it didn't, working on the rearend would have meant pulling the whole rearend out.
I had originally intended to use poly bushings in the link ends, but there is too much movement fore and aft. The bushings were going to have to flex in a direction that they didn't have much give. I swapped over to heim joints. If I was building it over again, I would use tie rod ends. That's what Chrysler did on the PT Cruiser. It has a watts link on the rear axle.
The center rocker can be raised and lowered in 3/8" jumps to move the roll center.
I still have some rough edges to clean up and most of it is just tacked together. I have a lot of welding left on the whole car. I'm waiting until I strip the chassis down so I can position it for better access.
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I must admit. I've never seen a watts link NOT mounted to the rear axle!
The picture(s) made me think about it's motion / travel... ;-)
I decided I needed to reinstall the rear body section to check some clearances and do some future build planning. To do this, I needed to repair the broken and bent rear body mounts. There is no way that these mounts can be accessed without removing the rear body section. That's another reason I decided to tear the car down in the first place.
These mounts were originally simple pieces of angle iron with a threaded bushing welded on. A 1 1/4" aluminum sleeve extends this bushing through the rear of the body. This body area is reinforced and serves to locate the body on the chassis. The aluminum sleeves are also used to mount the rear bumper brackets. The threaded bushing on the driver side was broken off. The weld appeared to be poor, with little penetration. You can see how much the mounts were bent. I could have used heat to straighten them, but decided to cut them off and build new ones.
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I built my new mounts differently than the originals. I salvaged the threaded bushings and welded them to short sections of DOM tubing. These were welded to a long flat bar that spaced them out for the body openings. The bar was slotted and bolted on with carriage bolts. The slotted bar gives me some lateral adjustment of the body position and the nuts can be accessed with the body on. I had noticed that the rear fenders were not centered over the chassis and this adjustable mount will allow me correct this.
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When I attempted to set the body section in place I got a surprise. The body wouldn't fit! The lower roll pan that wraps under the chassis was hitting the rear leaf spring mounts. I was 100% sure that I had the new "straight" mounts in the right place. After thinking it over, I came to the conclusion that the rear mounts had not gotten bent in an accident as I had thought. I don't think the body fit correctly from the beginning and whoever built this car purposely bent them down to "adjust" the body to clear the spring mounts. That explains why the bends were fairly consistent on both sides. The rear bumper was bent, so the car did take a little hit at some point, but probably not enough to bend the mounts. Chances are, the weld on the driver side bushing was damaged during the original bending and the bumper hit finished breaking it off. As I said earlier, it's automotive archaeology. My conclusions might be completely wrong.
I didn't really need the spring mount, so I trimmed it for clearance. I left most of it because it might come in handy for hanging the exhaust. If I don't use it, I'll remove it completely when I tear the car down for finish welding.
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This is after trimming. You can see the light colored scratches where the mounts contacted the body.
After the trimming, the body section slipped on just fine. At least it's looking a little more like a car now. I did manage to get the axle centered in the wheel wells this time around. The original axle was off center by about an inch.
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OK. It's been a few months and a lot has happened, including a little work on the car!;)
I decided to take a break from suspension and get a few other things done. I still have a long list and decided to concentrate on the fuel and exhaust systems. No particular reason for choosing those other than they needed to be done.
I wanted to run a decent sized fuel tank. I could only get about 10-11 usable gallons in the original Chevette tank. It was supposed to hold more, but venting problems made it pretty much impossible to fill completely. It may have also been a gauge sending unit error and I wasn't going to take a chance on walking to press my luck by running it down below "E".
I wanted to keep the tank bottom as high as I could so that exhaust wouldn't be more difficult to run than it was already going to be. Snaking around the watts link was going to be challenge enough. Four inches seemed like a reasonable number, so that wound up being the under frame depth. To get a fair volume, I had to build the tank up between the frame rails as well as having a section below.
The dimensions are 36x16x4 on the lower section and 26x16x3 on the upper part. This works out to 15.3 gallons. Not as much as I had hoped, but still better than I had. As you can see from the pictures, I added a small round sump to the bottom. I'm running an in-tank EFI pump and this gives a small quantity of fuel (.4 gallons) that won't slosh away from the pump.
Pump starvation is a real problem for EFI cars that are asked to go fast around curves. The really serious setups use a separate 1 gallon or so surge tank to feed the EFI pump that is fed by a separate low pressure pump. My setup is a simpler compromise that should work OK for street use. The tank has a couple of large baffles to keep sloshing down and some additional vanes on the bottom that funnel fuel toward the sump. The hole in the tank bottom is smaller than the sump forming a lip that should keep gas from crawling out under G's. This lip was formed down into a rough funnel shape, too. The watts link frame should offer some protection for the sump.
To keep from running the filler hose through the already small trunk, I put the fill pipe in the lower section. This required a large vent in the upper part. The vent hose is 3/4" and I am hoping that this will vent quick enough to allow reasonable fill-up time. It will eventually connect to the upper part of the fill hose near the gas cap and will only come into play when the cap is open. The normal running vent is a 5/16" line that will connect to a roll over valve mounted high under the rear fender.
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This is the large vent that I made for the top section.
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I built a pump module setup along the lines of a factory unit. It holds the Aeromotive 340 pump, return line and the fuel sender. It's hard to see in the picture, but the return line does double duty as the pump mount also. I made it from 1/2" tubing for extra strength. There is a reinforcing ring welded to the inside of the tank that the module bolts thread into. The gasket in the picture is Neoprene, but that was only used for leak testing since Neoprene isn't compatible with gas. I'll replace it with something else during final assembly. Most likely Viton.
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The small white parts are electrical bulkheads for the fuel pump. These are made from Teflon (PTFE) which is unaffected by gas or alcohol. They're sealed with Viton O-rings. I made them to the same general shape as the B+ connection on a GM alternator. That allows them to use the same insulating boots.
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The tank is built from 5052 aluminum. This is an alloy recommended for aircraft and marine fuel tanks. The aircraft part didn't mean a lot because aviation gas doesn't contain ethanol, but a marine tank will almost certainly see contact with water. I was concerned about corrosion due to fact that ethanol can hold a good bit of water. I try not to use ethanol, but that's just not always possible.
I actually had enough 304 stainless on hand to build the tank, but it was going to be pretty heavy. Since all that weight is behind the axle, I decided to switch to aluminum. However, I am definitely not an accomplished aluminum welder and this tank is the single largest project I've ever done in that material. I pressure tested it with 3 pounds of air and soapy water. I found 3 pinhole leaks that were fairly easy to repair. Considering that it should never see any pressure normally, I think that's good enough. I did add some doubling strips where it lays against the chassis and where the mounting straps lay.
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I noticed after getting it hung that I need to add some reinforcing where the mounting brackets are on the frame. It would be easy to for the steel frame bracket to punch a hole in the tank in an accident.
They say that disaster can strike in an instant and when you least expect it. I can testify to that.
Just about the time I was finishing up the gas tank and before I had it mounted, I was getting ready to attend a car show in another state. I had my 46 coupe under the carport (it normally lives in my shop) to load it for the trip and was trying to get my lawn mowed before a thunder storm came through. Suddenly the poop hit the fan as they say. As I sat on my mower, I saw a strong wind hit the trees in my neighbor's yard and I turned in time to see the shingles being ripped from my house in huge chunks. The swinging doors on my shop broke the chains that hold them open and were banging back and forth. I also saw the roof being ripped off my neighbors equipment shed and the power poles behind it torn down. I had just witnessed a small tornado and it quite literally went right over my head. I never actually saw it, but my neighbor who lost the shed told me later that he did. I don't think the funnel ever made it to the ground or maybe my house acted as a shield, but my guardian angel was most definitely looking out for me. I hate to think what kind of shape I could be in. As it was, I didn't get a scratch until I tried to close the doors on my shop and got slapped pretty hard by one.
It wasn't raining and there was almost no wind before all this happened. Just some rain clouds off in the distance like we get all the time. I wasn't the only one as several homes in town suffered roof damage and many power lines were pulled down. The "official" report said straight line winds, but I have to believe my neighbor. I also find it hard to believe that straight winds would have removed shingles from both sides of my house.
It vacuumed over a third of the shingles from my roof and pulled a large swath of siding off. The shingles that were flying around acted like super coarse sandpaper and damaged the paint on my truck, 46 coupe and my motorcycle. Most of the damage was just surface scratches, but one place on the coupe was ground all the way to bare metal. The wind pushed my 750 lb Goldwing about 3 feet backwards into my 46, but didn't cause any damage. The doors on my shop were warped and had to be tied shut. Our power was out for almost 2 days. Luckily I was able to get a roofer out pretty quick and get tarps on the roof so there was only minor water damage. My shop was full of mess that was blown in. Shingles, siding and leaves.
Of course, all this shut down work on the car for several weeks. The various insurance companies have paid and some of the repairs have been completed. The roof is back on, but the siding is still waiting. The shop doors took about 2 days for me to straighten well enough to close. My truck has been repainted and I actually sold the Goldwing with the scratches. The new owner said he would take care of them. The bruises on my arm where door got me have faded.
The 46 will eventually get a complete repaint, but insurance only paid for spot repairs. The paint is 20 years old and shows some age, so I'll pay the extra for a make over. That will have to wait for the Healey to be finished, since I have some other work to do on it too.
From where I sit now, I'm thankful that the damage was just to things that could be repaired. As far as I know, no one in town was injured. Compared to the utter devastation I've seen with other storms, it could have been much, much worse.
Now let's get back to building a car.
Glad to hear that you're ok with a minimal amount of damage. Since I'm in tornado alley I know exactly what you're talking about and at times it can sure be scary.
What state are we talking about? It seems these days tornadoes have no boundaries and can pop up at any time no matter where you're located. Sure wasn't that way when I was a kid.
WOW! I guess straight line winds are tricky. Glad to hear you are OK, everything else is replaceable..
I can attest that straight line winds can indeed cause that kind of damage - they hit one side of the roof, pushing the singles ahead of the wind, then as the wind goes over the peak of the roof it "rolls", forming an extreme low pressure area on the opposite side and literally lifts shingles into the wind. Saw a brick wall in Corpus Christi that had two layers of bricks, face to face with a brick cap on top and the wall was standing after the hurricane winds, but on the downwind side about 1/2 the height was pulled away by the vacuum formed by the 200mph winds hitting the face. Imaging the damage those bricks caused getting sucked off the wall, then flying at 200mph velocity impact!!
Glad that you're OK, and that your damages were not worse. "Stuff" can be replaced, but lives gone are gone.