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05-02-2007 09:59 PM #1
The recaps you have, are "show car" tires and not really designed for drag racing. If you go to a real drag slick or a DOT drag slick you will notice a big difference in traction. Caldwell Tires in Pasadena used to be the place to buy recap slicks in the Los Angeles area years ago, but they are now gone.
We have had great racing success with M&H tires. They are sensitive to air pressure changes and need a good burnout before going to the line. We run our slicks tubeless and you will be surprised how much lighter they will be than your recap tires when installed. Just call the national M&H distributor Hashim's in Bakersfield, CA and ask for John Hashim. Nobody knows more than John who has been in the game a long time. Tell him The Palmer's VW team recommended you.
I also agree that putting more spring weight on the right rear will help out on our launch with an open diferential. Maybe look into a stiffer rate coil spring on that corner if running a coilover four bar set up? I always felt that if you could set-up the car to launch well with a open differential (by correcting corner weight), then going to a limited slip would be the best set-up.
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05-03-2007 08:45 AM #2
Tech's comment about pre-loading an open diff car's rear axle - and sometimes the left front - is an excellent point.
As a small fwiw, both my roadsters have the battery mounted low in the frame, right side in front of the rear axle.
May as well put the weight where it will do some good.
Back in the day, little brother and I ran a C/Gas car - 50 Ford coupe w/built Olds Rocket motor.
Traction aids were:
Recap slicks, hard ones, this was just a couple years before wrinkle-wall slicks came out.
Open 4.27 diff.
Traction Masters - home-made, they look like the bottom half of a four bar setup: they control wheel hop and aren't much in the chassis tuning dept.
A couple of aluminum spacer blocks in the left front coil to put some weight there.
Air Lifts - an air bag inside a weak coil spring that goes between frame and rear axle. Air Lifts were designed as a load carrying assist device, but it wasn't long until the drag racers figured out what they were really good for.
We 'tuned' the chassis by doing short burnouts at the back corner of the dragstrip and taking note of the tire marks.
Black all the way across indicated proper tire inflation - dark in the center = too much air, dark on the outside edges = not enough air.
Comparing the black tire marks from one side to the other, if one was darker than the other, that indicated too much weight on that tire and conversely, not enough weight on the other.
Adding or subtracting air pressure from the Air Lifts would even out the marks.
Results with the early daze chassis tuning stuff meant that we could launch against a posi equipped car that didn't have a particularly well tuned chassis and hold our own.
It didn't take the other guys long to learn though and once they went the air lift weight jacking bit things got tough.
When they bought wrinkle wall slicks and we were still running our old-style hard recap slicks things were pretty much all over for us.
You may want to keep in mind how little wet weather traction there is with slicks - or cheater slicks - run on the street.
As well as many of today's soft, wide, fat radials work quite well in street use when installed in powerful lightweight coupe/roadster type cars....C9
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05-03-2007 12:43 PM #3
....WOW, this is a lot of info for me to digest! THANKS for ALL the replys....
..... I need to start out with the 'less expensive' ideas & go from there. I had this same motor {less 20 HP} in a 2850 pound Camaro & all I did was put a traction bar set up on it, posi rear, & real wrinkle wall slicks. To drive it I just put it in drive, punched it & held the wheel straight. 400 pounds less makes a WHOLE lot a difference. A TOTALLY different animal!!!... Yes, I need to work on driving technique. I tried the 'feathering the throddle' & 'punching it from a roll' yesterday & it works a lot better {actually pretty good}.... I was supprised to hear that even all out drag race cars DON'T hook well on the street! My battery is right behind the rear seat in the center. May be I should move it to the trunk & over the right rear tire? But the fuel cell is in the trunk so I'm leary of putting the battery there. I'm going to get the lower geared posi & then try the tuning methods r/e; looking at the burn out marks to make sure they are evenly colored on both sides. Although I didn't realize that the posi unit will handle differently in a 2450 pound car verus a 2850 pound car.
After I do this stuff I'll try the M & H tires. I didn't reallize that I have 'show tires'. May be that's WHY they look so good!!! I least I like the look!!! .....
I don't know that I want 'the look' with an air shock on one side. So I'll try the other stuff first. Although the stiffer rear spring on the right side is an option....
THANKS again, Bill
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05-03-2007 06:54 PM #4
You can take tha air shocks and set them up as individuals instead of in a pair. that way you can adjust the Air Pressure in one side and it wont effect the other. If you lower the right side by 5-10 lbs it will change the way the car hooks dramatically. (This will allow more movement in the suspension and in effect transfer more weight to that side)
There is a drawback to this as it makes the ride a little weird. The right rear will feel like it has a broken spring or a really soft spring. Easy fix is to have your air shocks attached to a mini air compressor with pressure guages and release valves. You can make adjustments on the fly without ever getting out of the drivers seat!
And to get to the issue of the battery in the trunk with the fuel cell. If the Cell is properly vented and the battery is located in a secured battery box you shold be OK. We have a 22 gal fuel cell sitting right next to our Optima battry in the racecar and have never had any issues. Even when I welded my wedding ring to the frame with my finger still in the ring! (Long and painful story)
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05-04-2007 07:42 AM #5
Not sure if I've posted this before.
Battery box made from 1" x 2" rectangular tubing.
It works well in this location.
I use an Optima nowaday, but the original battery was a DieHard.
Since it's cool under the body - as compared to the engine compt. - I only had to add water twice in about a 4 year period.
Cables are no problem.
There are insulated bulkhead fittings available - Speedway for one - and you can combine standard length battery cables to get to the solenoid/starter.
Cable from battery to master disconnect switch, cable from switch to supply panel/Ford solenoid under the seat, cable from Ford solenoid to GM solenoid at the starter.
Works well . . . use the large #1 cable.
Same deal for the ground cable, ground it several places on the frame and especially ground the engine to the frame.C9






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I bought the 76 in August , but haven't been able to work on it. When I get a chance I'll post some pictures.
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