Traction Advice Pure Stock
 

I have 2 completely stock 1965 GTOs that can't find traction on a soft M & H tire's.

One is an automatic and other is a 4-speed, both react the same way when leaving on the green, like a snowy winter launch. :--)

It's a bit odd that a 4 inch "street radial bias look" from Coker will perform slightly better than the 8 inch M & H tire.

I did all the air pressure adjustments too.

They both are survivor type cars that I'd like to keep that way for the next generation to enjoy.

Any ideas for improvement without making any permanent changes?

https://imagizer.imageshack.com/v2/8...922/hHocxq.jpg

What is the current set up suspension wise? GM A bodies are one of the easiest cars to get to hook iMO.

Look on youtube, Horsepower Depot, he goes over how to get a FAST car to hook.

Mike, the suspensions are completely stock.

P.J. Yes Horsepower Garage is a good channel. Almost embarrassingly so to the competition how they can run that hard on F70 Firestone's. Even with the technology they run, power is power.

Are the cars just spinning or wheel hopping?

This would be where I would start:
Boxed Factory Lower Control Arms
Bolt on sway bar from 70 model (or aftermarket)
Good Bushings
Factory style 4 speed triangulation braces
possibly upper no hop bars or lower relocation brackets from UMI.

Spinning, no wheel hop -- like still in the water box.

I'm just surprised at how hard it is to get some bite.

I appreciate your input, thanks.

(In my previous post I meant Horsepower "Depot" not Garage, I've been enjoying the YouTube channels for sure)

Anyone look to see if water was dripping from wheel wells?

Some cars are worse than others on that. My old lemans was bad about it. A friend caught it when he went to put down some track-bite. Started dodging the box and doing dry burnouts after that. Went from spinning in water launch to stripping the guts out of stock converters

Clay

That's a good point. This weekend I'm giving the radials another try, with little or no water.

I used to watch Jim Mino launch his RAII Firebird and I can tell you for sure he had developed a technique that involved applying just enough power to hook without spinning the tires but it took a HEAVY toll on the clutch. He told me one time that he was so good at changing out the clutch he could roll under the car and swap one out at the track if needed and most times get it done before they called him back to staging for the next run.

From what I've seen you don't want to "smack" those type of tires like we do race slicks, drag radials and DOT type bias ply race tires. The compounds in those get sticky enough with a good burnout to hook well when hit with full power.

You might want to wonder over here:

https://www.facebook.com/groups/765517070206972

You may get some good advice from some of those folks, several of which race Pontiac's........

Jim and I use to talk about traction with red lines. He noticed some of the other cars had tire on their quarter panels. Thinking maybe a a softer compound was available to some. Experiment with adjusting shocks,bushings.

Drive around the water box, not through it.
Back into it enough to get some water on the tires and then pull back forward.
Do a solid burnout.
Look at the track ahead of you to see if there are any spots from the guy that just ran.
On my car I tack up to around 2500-3000 and on the third bulb lift the brake and roll into the throttle.

Once you find the technique that works, you can do it every time.

At the Pure Stock Drags we usually have several A-body cars from 64-74 at each race, every car responds differently, some need hop-stop bars (which we recommend on all A-body's with both trans types since they apply downforce leverage proportional to the power applied, so always more pressure on the tire patch), some don't. My TH400 RAIV '70 Judge runs 12.80's with it's factory original (old!) suspension. Dan's '71 TH400 455HO T-37 needs Hop-stop bars and old front shocks (loose) to get it to hook (12.50's). I'll be racing my 'new' '70 Tempest 330 hp 400 with a TH400/3.42's this May at the F.A.S.T. race and it has an original rear suspension without the hop-stop bars. It shouldn't need them as the previous owner raced it with a 461 making 475 HP/550 TQ and he ran high 11's without wheel-hop but on 275R60/15 drag radials. We have found over the 30 years of doing the pure stock drags that the repop Firestone and Goodyear fiberglass belted bias ply tires hook pretty good with 35-40 lbs of pressure. We let the 64-66 A-body's run them as well in black wall, red or white line (no raised white letter to maintain the factory look).

Obviously, a rear suspension with new rubber bushings (or poly if you want) with good 50/50 shocks and the rear sitting at the stock (low) height with G70x14 repop tires should work well. You can also add spacers (washers) under the front sway bar brackets, install old worn shocks or 90/10's up front and install A-arm bushings without the serrations to improve lift at launch. Try bouncing your front end at the bumper...if it's stiff and doesn't move much, that is limiting the cars ability to transfer weight at launch. If it moves quite a bit both up and down, that will help on the track (not on the road).

At our event, we have the track prepped for street tires, so it is 'glued' the first 1/8 mile and the sticky stuff reapplied at the line every hour and between rounds on race day. We don't use the burn-out box, so no water ever for treaded tire, and as Boss said, drive around it not through it so you don't have water in the front tire treads to drop on the track at the line.

I hope this helps. Dennis

Guy's, thank you for your input and good information. I'll go through these items one by one. If you see this car in the pits at Lebanon Valley please say hello. It's a good honest 1965, however it was slightly neglected, storage wise by it's first owner.

https://imagizer.imageshack.com/v2/6...922/fOZ8gl.jpg

That's a nice '65 and it runs great from what I recall i an earlier thread (14.40's?). Best wishes on finding that elusive traction.

Dennis

I always carry a spare driveshaft.When I was a teen I witnessed a guy drop a driveshaft then try to find parts to get home.That made an impression.

I'd put a rear sway bar on since they are plentiful and cheap addition with boxed control arms and teflon bushings. What rpm are you launching? Do you have a posi in those cars.? And go around the water.

Mike Davis & Straycat both mention a factory rear sway bar with boxed lower control arms that have teflon or polyurethane bushings in them along with the braces are very helpful for better traction due to stiffening the chassis distributing the load more evenly to the rear tires. The '70 Tempest I mentioned does have all the above (not so sure about the bushings though...can't see them) and I'm sure that's why it went high 11's without wheel-hop and had good 60' times (1.6's with the drag radials). It doesn't have the hop-stop bars however.

Dennis

The launch RPM is low, either from idle or up to 1500. Off idle is fun, I flip the clutch out and roll into the throttle. almost feels like an automatic with a stock converter. As a matter of fact, the 4-speed car and the automatic run within .01th of each other when I use that method with nearly identical MPH.

If I bring it up to 1500 or higher it's more of a balancing act of traction and fear of walking home :--)

Both cars have open rears with the Pontiac standard 3;23 ratio.



Years ago I read that the Reynolds Buick went 14.00"s with headers, slicks and 4;10's with their 1965 Gran Sport. Personally I went 13.87 with a bone stock 1965 442 automatic with 3;90 gears.

I'm trying to run 13.99 (or better of course) with a stock tire because that seems like a very good stock benchmark for a 1965 4bbl. GTO manual or automatic and I want to carry the good Pontiac name, I'm a biased fan. :--)

These short videos are from last year, the 4-speed went 14.44 and the auto went 14.45.

https://www.youtube.com/watch?v=5ED-...hannel=NYS-GTO
4-speed

https://www.youtube.com/watch?v=Zmxt...hannel=NYS-GTO
automatic

I always used air bags in my gto’s and grand am worked well

That might be your whole problem.