Don't know anything about the existing cam except that it is not stock.
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Don't know anything about the existing cam except that it is not stock.
The heads are being supplied with stock springs and retainers. Valves have a 3 way grind
I've found a guy that has a set of Comp Cam b hive springs 26915 new in the box for $50. Looks like they will work, any comments?
To bring you up to date, I may be going over board with the heads but more is good right? I picked up a set of vortec heads on eBay from a head shop, they are the 906 castings. Took them to a local head shop and they checked out good and are in prime original shape. I ran accros a guy on a local web site that had recently bought a house with a lot of stuff left in the garage. He advertised comp Cam b hive springs no 26915-16, retainers no 795-16 and seats no 705-16 all for $50 so of course I picked them up. I still need to get locks but don't know what I need. I've also got the Mr Gasket pin kit. I have the Eldebrock AVS thumper 650 carb and the eldebrok RPM manifold is on order. Not sure what push rods I need and with the new springs what Cam specs I should be looking at. I think I'm going to be WAY over 300 hp, but that's ok. Might as well go for 400. Any help you can give would be appreciated.
Have you called Comp and asked them yet?
Been talking with comp Cam and found out that the springs were supplied with the wrong retainers for my application so I've ordered their recommended retainers and locks. I also asked there tech group what Cam they would recommend their response was Cam kit k12-423-8 502/510 lift, 224/230 duration @ .050 on a 110 lsa. I would really like some comments on this Cam from you guys that understand this stuff better than me. I will be running 4.10 greats.
Just checked out the Cam kit....don't need all the parts ant too many $$$$. What about the specs?
That cam will want a static compression ratio of about 10.00:1. Current thinking is that an iron-headed street motor should be capped at about 9.5:1 because of the propensity of pump gas to detonate with iron heads. My thinking is that if you carefully de-burred everything in the combustion chamber, on the piston crown and the spark plug electrodes and threads and used a fuel/air ratio sensor in each collector of the headers to set the proper fuel mixture, you could probably get by with the 10.00:1 static compression ratio on pump gas with no detonation. You would also need a tight squish/quench of 0.035" to 0.040" to create turbulence in the chamber just as the spark plug fires.
The cam is one of Comp's Extreme Energy grinds. I personally do not care for this technology, but some fellows are OK with the noise generated by the extreme ramps. With the 110 degree Lobe Separation Angle, it will be difficult to create much intake manifold vacuum for power brake operation, if you have power brakes. Power begins at 1900 rpm's, so you will need a minimum of 2,500 stall in the torque converter.
My best guess is that you told them you wanted a lumpy idle and this is what it costs to have a lumpy idle. Everything else has to take a back seat.
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Didn't ask for lumpy idle, just asked for their recommendation, not even set on a comp Cam yet. I would prefer to stick around 9.5:1 compression. Any recommendations at what I should be looking at? Comp Cams did say that with the heads/springs/retainers I have that I am limited to a max lift of .525.
How would I do it ?
0.030" overbore to 4.030"
Stock stroke at 3.480"
Cubic inches 355
L31 heads with ~65 cc chambers (chambers generally pour a little larger than advertised)
Keith Black KB193-030 hypereutectic pistons w/ 5/64" rings (makes 9.5:1 SCR) This piston has a compression height of 1.561", so I would cut the block decks for a block deck height of 9.001". This will make a zero deck motor. (1.74" crank radius plus 5.7" rod length plus 1.561" piston compression height equals 9.001"). Using a Fel-Pro 1003 head gasket that compresses to 0.041" will give you a 0.041" squish/quench and will insure that the motor will run on pump gas without detonating.
Have your machinist insure that the angle between the heads and the intake manifold is zero so that there is no leak. If there is a bottom gap due to differing angles between the manifold and the heads, this will allow the motor to suck oily vapor from the crankcase every time an intake valve opens. Often, this is mistakenly blamed on valve seals or the piston rings not sealing up. So, make sure the intake manifold and the heads are dead nuts parallel top to bottom and end to end before final assembly. THIS CANNOT BE OVER-EMPHASIZED. if the gap is at the top of the ports, it can be found by spraying a combustible mixture onto the manifold while the engine is running, but if the gap is at the bottom, no such finding is possible, the motor will be an oiler and there is nothing you can do about it except disassemble and re-machine the surfaces or buy new parts and cut them to fit. Your machinist will know what to do it you show him this post.
Knowing what I know about motor oils, I will never recommend a flat tappet cam in today's world. Anyone doing so is just asking for trouble unless he takes various precautions and includes an oil supplement with every oil change. Extreme lubricants phosphorus and zinc have been eliminated from off-the-shelf motor oils, so you must add these chemicals to the oil in order to insure that the lifters will not frag the lobes of the cam. There are other precautions that can be taken if you just absolutely have to use flat tappet lifters......
http://www.crankshaftcoalition.com/w...ips_and_tricks
With 9.5:1 static compression ratio, my pick of cams would be a hydraulic retro-fit roller, Howards # CL110235-12.
https://www.summitracing.com/parts/hrs-cl110235-12
The lobe separation angle of 112 degrees will allow production of more intake manifold vacuum for power brakes. This is always a back and forth choice, with a smaller LSA favoring more low end power, less top end power and less intake manifold vacuum or a cam with a larger LSA favoring less low end power, more top end power and more intake manifold vacuum. Regardless, if you have power brakes, you need to address that need as well as the need for power. Most OEM cams are ground between 114 and 117. Most hot rod cams are ground between 112 and 106. You will have to figure this out for yourself. I made the choice of 112 for you because I think this will make enough intake manifold vacuum for power brakes and still make good power. Everything in a street motor is a compromise.
Intake duration at 213 is perfectly matched to your 9.5:1 static compression ratio. This cam will work with a 3-speed or 4-speed overdrive transmission. I would match it up with a 28" tire and a 3.50 to 3.73 rear ring and pinion with a non-slip unit of some kind.
I would use a minimum 2000 stall converter and a 2500 might work even better. Use a 10" unit that is build for the purpose rather than a 12" converter with the fins bent over.
Use 1 5/8" long-tube headers with an X or H tube installed immediately after the collectors. You may also want to install an air/fuel ratio device in the collectors that will tell you whether the mixture is rich or lean. 2 1/2" pipes from the collector to the rear of the vehicle with mufflers of your choice somewhere along the way will be fine. I like to run the pipes all the way to the back bumper to prevent my ride from sounding like an amateur build and reverberating the sound under the vehicle against the body or bed sheet metal.
Use a 14" diameter X 4" tall air filter assembly so the motor can breathe.
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Wasn't planning on doing anything with the block. Has good compression (see numbers in earlier post) and doesn't burn any oil. $$$$ are main reason. Also as stated earlier I've got a TH350 tranny, no overdrive. Would the suggested Cam, gaskets and other top end items still be a good fit?
I keep hearing that using a flat tapped Cam is a no no. I've got a 1969 sbc with vortec heads so from what I've read it allears as though I would need to use a retro fit roller Cam which are pretty pricey. Tech inspector 1 gave me a great plan above but I don't have the money to do everything he has suggested. If he or others could help me out on some of decisions I need to make it would be appreciated.
The engine in its current state runs good, has consistent compression on all 8 cylinders and burns no oil.
Transmission is a 350 TH recently rebuilt with installation of a Trans Go shift kit. I know I will need to change torque converters. Looking at a 2500?..
Need to change rear end to a 4.10 ? With posi.
Need a Cam that will work between around 1800 to 5500 rpm.
Will be putting on headers with an H cross.
When pulling the heads I will determine if I will look at pistons to see if I need new ones , suggestions on what I need would be appreciated.
Once I tear into the engine in my 76 Vette the cam and lifters will be replaced by a Howard's flat tappet cam. There are only a couple of manufacturers I would trust and Howard's and Isky are two of them. IMHO, the rick to breaking in a flat tappet cam is spring pressure and the proper oil. I will break in the new cam with the worn springs currently in the engine and some ZDDP additive. After the cam is broken in I'll apply air pressure to each cylinder and replace the springs with the ones that came with the cam.
I keep hearing about money as a barrier to doing the build correctly. I've told the story many times that I was on a budget of $50 per week when I was building my '27 T roadster. I wanted a set of All American coilover shocks for the front that were $550, so I had to wait for 11 weeks to get them.
The proper way to build a motor is to begin with the bare block and have your machine shop verify the mains and cut the decks to ZERO, based on the "stack" of internal parts that you will use. Then, the thickness of the head gasket will determine the SQUISH/QUENCH, which should be 0.035" to 0.045" ideally. Cutting the block decks will also give you a "square" block that will allow the heads and intake manifold to seal up and insure that all combustion chambers are the same volume to make a good motor. If you or anyone else reading this thinks that the decks or anything else is square on a production block, then I have some land in Florida that I'd like to sell you.
You can half-azz the build if you want to, but I really don't want to be a party to it. Now, sit down with your wife, make a REAL budget for the build and stop being silly. If it's $10 a week, OK, it's $10 a week. I can show you how to make a flat tappet cam live in your motor, but it takes some doing. NTFDAY (Ken) knows how to do it, look at the post just above this one. Here's the rest of what it takes.....
http://www.crankshaftcoalition.com/w...ips_and_tricks
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i have at least 20 builds out there with grate motors and flat tappet cams . new cam, new lifters and correct break in is all important . so far i have not had a failure. but in any future builds i will use ls motors or at least go roller motor . my days with mr. goodwrench truck motors are over. i can score an ls1 with trans and all acc for around 2500-3000 .
i remember those days Tech . it took me about 4 months to buy my first set of cragars . could only buy one at a time .
Has anybody heard of or have experience with PRW lifters? Should I just forget about using roller lifters and stick with stock lifters
I hear you guys and I don't need to seem whiny. I'm retired with my only income is SS. I can budget things out but will be a very long process. Here is where I'm at now.
Vortec heads
Comp Cam beehive springs with retainers and locks
Mr Gasket stud pin set
Edelbrock AVS 650 carbuator
Edelbrock RPM intake
What I know I need
Headers
Mufflers
Posi rear end and new gears
New torque converter
Rocker arms
Push rods
Bolt and Gasket sets
Valve Covers for Vortec Heads
Cam and lifters
I've got about $3,000 to finish off the the above and anything else I can accomplish. Any thoughts where I can save $$$$$ ? I'm not comfortable replacing the rear end myself. I've worked on engines and trannies but never differentials.
Ever thought of buying somebody elses project motor complete?? I had a buddy, he bought a show car with a motor (454) with less than 3000 miles and sold it to the machine shop for 600 complete, every bracket everything because he wanted numbers matching, there are a zillion take outs out there, same guy just sold his Novas small block complete carb to pan for $800 with edelbrock heads and new carb, you could drive the thing it ran great, sometimes building a motor is way more expensive than buying a crate or take out, just know what your getting and check it out well, my thoughts of being on a budget, nothing wrong with having to be conservative but building is generally more expensive I have learned.
Heck your talking small block stuff here, its not rare. Yeah my next motor will have roller lifter but do it right if you do flat tappets, check the cam manufacturers recommended oil and break in procedure, not a bunch of strangers on the net, you ask 10 guys and get 10 answers (though those on here are really good) but fact is if that cam goes bald and you tell Isky you did what Joe on the net said they will not only laugh they will most likely tell you see if he will warranty it then and your out at least $300 more. I use a flat tappet Isky( hemi build) and they where VERY clear on what to use, they said Brad Penn, not his break in oil, just straight Brad Penn period, I called and asked about using Brad Penn break in oil and the tech said, did it say break in, I said "No" and he said then don't use it. Use there recommended oil afterwards and drive the hell out of the thing, like we did for 50 years with flat tappet motors with the right oil.....Best of Luck
As I have said many times, the problem with using a flat tappet cam in today's world is that the oil companies have removed extreme pressure lubricants from the oil that used to protect the contact point between cam lobe and lifter. I'm going to post this link again because it includes all the information that you need to make a flat tappet cam work in today's world.
http://www.crankshaftcoalition.com/w...ips_and_tricks
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Did some shopping around and picked up a 010 block already bored 30 over and recently honed. Guy totaled his camaro and was parting it out. Came with speed pro hypereutecic H 6180 30 over pistons with stock rods and caps. Guy also threw in a Summit aluminum Cam cover and cam button. All for $280. Looks pretty clean, no ridges on cylinders. Taking to a shop next week to get checked out. This approach will delay completion of my build but will hopefully work out for the best
Going to try and stay as close as I can to techinspecror1s recommendations. Old guys can still learn but we do it at a slower pace.
So with the added cost of block work I thinking that roller rockers may not be the best choice. Having vortex heads that require self guiding narrow body rockers I'm thinking about going with the summits sbc rocker arm kit no 12495490. Any comments? I would still be going with a Howard retro fit roller cam.
If I didn't want to spend the money for Scorpions, I'd use the 12495490's. When you do the first mock-up of the motor, pay close attention to the holes in the heads where the pushrods come up through from the tappets and make sure the walls of the pushrods are not rubbing on the iron heads. There are 3 ways to center the rocker over the valve stem tip on a SBC, by using rail rockers or guide plates or the factory production holes in the heads where the pushrods come up from the tappet. You can use ONLY ONE of these methods. Using two or more will give you a headache, trust me. So, if you are using rail rockers, you have to clearance the holes in the heads and NOT use guideplates. You can use a Louis Tool as a guide to cut the holes in the heads a little or you can just get in there with a rat-tail file and enlarge the holes by hand to prevent contact.
Every good build should include making certain that the pushrods are the correct length. Here is the very best guide to accomplishing that.....
https://www.youtube.com/watch?v=o5is9BsH5OU&t=2s
I'm pretty sure this is the piston you mean, H618CP......
https://www.summitracing.com/parts/s...make/chevrolet
These will do a great job in a street motor and are the correct piston compression height (1.560") to keep the stock dimensions on the factory stack of parts (9.000") Cutting the block to 9.000" and using a Fel-Pro 1003 will put the squish-quench at 0.041" and will also leave the motor ready to accept aluminum heads with a 1003. You have not mentioned aluminum heads, but that is normally the next change that a fellow will make, so I wanted to address it here.
Usually when fellows bolt on a set of aluminum heads, they use the stock block deck height ~(9.025"+) and use a thin steel shim gasket to set the squish at ~0.055"-0.065" or so (not thin enough to generate a good squish/quench). The aluminum heads and the iron block grow and shrink from hot to cold at very different rates and the material on the softer heads can be abraded (called fretting, where material is actually removed from the heads in certain places along their mating surfaces) and the head must be re-surfaced to use it on another build. This can be eliminated by doing it properly in the first place. Every aluminum cylinder head manufacturer that I know of recommends a composition material head gasket for use with their products. This allows a little "give" between the heads and the block as they heat and cool and prevents the fretting of the aluminum material. It's like bolting the head onto a cushion where it is free to move around a little without doing any damage. Pretty cool stuff, huh ? The GO-TO gasket for a SBC is the Fel-Pro 1003 that squeezes down to make a 0.041" squish/quench when used with a 9.000" block deck height and 9.000" stack. Oftentimes, fellows will find that they can drop down one or two grades in octane and still not experience detonation from their motor by following this prescription.
This is why I try to convince every hot rod engine builder that I talk to to cut the block decks for a zero deck and use the gasket thickness as the squish/quench. You'll need to work closely with your machinist though, and make absolutely certain that the heads and intake manifold will bolt together with no gaps top or bottom to make vacuum leaks. Your machinist will have formulas to get everything to fit together like a glove and not leak. The worst scenario is to put the motor together with a gap at the bottom of the head/intake manifold ports. You cannot find this vacuum leak with a combustible material such as spray ether like you can if they are gapped open on the topside, so every time an intake valve opens, that cylinder draws in oily crankcase vapors from the bottom of the ports that make the builder think that it may be rings or valve seals that is causing the motor to oil when it is actually caused by a mis-fitment between the intake manifold and heads.
GET EVERYTHING FLAT AND SQUARE IN THE FIRST PLACE AND YOU WON'T HAVE THESE PROBLEMS. WORK CLOSELY WITH YOUR MACHINIST. if your machinist won't spend time with you addressing these problems, find another machinist who will. This is too important to do in a half-azzed manner.
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I will be buying a new crank for this build. Any suggestions?
If replacing just the crank, i would ask the machine shop if they have one that will magnaflux good. A cast crank will work just fine for your purposes. If you needed more than the crank, like pistons too, you might opt for a 383 kit from Scat or Eagle. Otherwise, a cast crank off craigslist will work just fine, have the machine shop magnaflux it for cracks and maybe turn it down to the next standard diameter for use with undersize bearings. They will turn 0.010", 0.020" or 0.030" undersize on the mains and/or rods.
I've been checking on limited slip units. It seems to two most talked about are the Auburn Gear cone/clutch units and the Eaton disc units. Any comments or recommendations between these two. My only experience was with the late 60's GM units.
I think Auburn would get the nod if it were mine.
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The block I have has a no by pass oil filter attatachment. Any comments about this? Should I keep it or go back to a standard by pass type?
I'm putting an Eldebrock AVS carburator in the el Camino and find one area of the instructions confusing. There are two distributor vacuum ports on the front of the carb. Facing the carb, the instructions say the one on the left (passenger side) should be used for emission controlled cars then later on it say it's for a full vacuum advance distributor. The say the one on the right (drivers siide) is for non emission control cars. My engine has a hose running from the valve cover to the air cleaner and has a GM HEI distributor. Any idea which side I should be hooking up to?
Go to this site:
http://www.crankshaftcoalition.com/w...op_dead_center
Scroll down until you get to this title:
FACT AND FICTION CONCERNING VACUUM ADVANCE....
Start reading....
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Crazy good link Tech. Thx.
Thanks Tech! That article clarified everything!
Got the block back from the machine shop, washed out, squared, new Cam bearing, new soft plugs and a fresh hone. Machinest says for best reliability I should use cast iron rings, any thoughts? Also got in the Yukon Posi and Richmond gears to be installed on the 15th. Looking at getting a Scat crank and Speed Pro competition main brings as well. Any input on these selections would be appreciated.
Let's let Hastings clear the air for you concerning ring composition.....
https://www.hastingspistonrings.com/...ecommendations
You should also know that different compositions require different hone finishes on the bore. Cast iron requires a rougher finish and in my opinion, will not last as long as a moly-faced ring which requires a smoother bore finish. Ask the machinist for an estimate in his opinion of the service life of cast iron versus moly-faced. If he says the moly rings will last longer, but require a smoother bore and are more expensive, then it is up to you as to whether or not you want so spend the additional jack for additional service life. I would expect a cast iron ring rebuild to have a service life of 60,000 to 75,000 miles, while I would expect a moly ring rebuild to have a service life exceeding 100,000 miles. I'm not sure what the OEM's are using for piston ring material, but my 2004 Ford F150 SuperCab has over 235,000 miles on the little V8 motor, uses very little oil and still has good power.
As far as ring width, that is governed by the width of the ring grooves in the piston. In the past, you could order either 1/16" (0.0625") or 5/64" (0.078"). I have always preferred the wider ring for a daily driver and the narrower ring for a strip or street strip motor. The narrower the ring, the less tendency it has to flutter (and lose seal) at higher rpm's because of its lighter weight. The wider the ring, the more surface area it provides to effect a good seal against the bore. Current thinking is to go with narrower rings, which will lend a little extra horsepower and therefore, mileage. Of course, if you are not changing pistons, then you will have to use the ring width you have now.
Don't know anything about Yukon, but have used Scat parts since Noah was a teenager. And of course, Speed Pro has been around forever.
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Mechanic said I could expect 100,000 with cast iron. Older guy and I'm not sure he's up to date with newest technology. Hasting site has be thinking about cast or Molly. I could expect extended periods of operating around ,3,000 rpm but have never seen temp go over 190 in it's present state
Trying to get more info on my block. It has a casting stamp of GM3970010. Engine code V0412CKH and partial vin 17R457174. Any info, year, 1 or 2 piece rear main, main journal size, etc would be helpful.
Try this site Small Block Chevy Engine Codes - Page 1
010 block is very common and CKH is 73-74 350
3970010 was cast between 69 and 79 and was actually in some 302 engines but most predominately 350 in both 2 and 4 bolt configurations in cars and trucks.
V0412CKH translates as follows:
V = Flint assembly plant
04 = April
12 = 12th day
CKH was found on the following:
CKH 1972 307 with a Powerglide in F A X/Apollo/Ventura
CKH 1973 350 m/t, 4 spd, (L48) in F A X/Chevelle/Monte
CKH 1974 350 m/t,3 & 4 spd, (L48) in F A X
Your complete VIN probably starts with 1C80 17R457174
1st digit – This is the manufacturers identity number, 1 is Chevrolet
2nd digit - This is the Model Series, “C” is El Camino. If it is a “D” it is a Custom El Camino
3rd and 4th and digits - body style, 80 is 2dr Sedan Pick-up
5th digit is engine size and it’s always a letter:
D = 250cid L-6 1-bbl (L22)
F = 307cid V8 2-bbl (L14)
H = 350cid V8 2-bbl (L65)
J = 350cid V8 4-bbl (L48)
U = 402cid V8 4-bbl (LS3)
W = 454cid V8 4-bbl (LS5)
6th digit the last digit of the model year (engine replaced with a 1977?)
R = Arlington, TX (7th digit - This is the Assembly Plant code)
457174 = (8-13th digit, Sequential Production Number)
Hope this sheds some light,
Glenn
Thanks for the response. Very helpful.