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Discussion Starter #1
Hi all,
Just tuned my 69 and she runs awesome. When I'm sitting still or on a slow roll and hit it, all I get is wheel hop. Looking to burn some rubber from the tires but not having much luck. Any thoughts. Will a rear sway bar help?
 

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Sway bar probably won't help that. What's your rear suspension setup like... factory arms and rubber bushings?

Bear
 

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Usually, a lifted rear suspensionis the culprit. There are no -hop devices available if you want to run with it jacked up in the rear and want to eliminate hop. Stock suspensions usually are pretty good about not hopping. It's all about pinion angle and load. Google No Hop bars for GM for more info.....
 

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Discussion Starter #4
Thanks for the replies. Factory areas and rubber bushings it is. Rear sits a little low especially with a full gas tank even though the spring are new (previous owner installed). Kinda don't want to put anything that will make it all jacked up in the rear. I'll take a look at what's available on the web. I was hoping this would be an easy fix.
 

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Here's the answer to all your suspension questions http://www.dickmillerracing.com

I actually typed out a rather long answer yesterday morning but my computer locked up :willy: when I submitted my reply and I had to be off to work.

Flex in the stock control arms, bushings and too short of an instant center on the stock suspension is the Cliffnotes version. Dick Millers book is a great reference and he defininetly knows how to get a GM A body to hook!

Edit: Some people might call him "Richard" Miller lol. Dang profanity editor :shutme.
 

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Here's the answer to all your suspension questions _ Oldsmobile, Suspension GM & Cutlass & Chevelle & Ford: Dick Miller Racing Oldsmobile Performance Parts.

I actually typed out a rather long answer yesterday morning but my computer locked up :willy: when I submitted my reply and I had to be off to work.

Flex in the stock control arms, bushings and too short of an instant center on the stock suspension is the Cliffnotes version. Dick Millers book is a great reference and he defininetly knows how to get a GM A body to hook!

Edit: Some people might call him "Richard" Miller lol. Dang profanity editor :shutme.
I corrected the problem with the censor,
 

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Thanks for the replies. Factory areas and rubber bushings it is. Rear sits a little low especially with a full gas tank even though the spring are new (previous owner installed). Kinda don't want to put anything that will make it all jacked up in the rear. I'll take a look at what's available on the web. I was hoping this would be an easy fix.
My first suspicion would be the rubber bushings, especially if they're old and worn. A fresh set might tighten things up 'just enough'. With factory control arms though you DON'T want to put in hard urethane bushings. The geometries involved would make everything want to bind up in turns, maybe bending/breaking things. The real fix is to replace the factory arms with aftermarket pieces that have some sort of spherical joints on the ends (OK if they're just one one end for the uppers). This kind of joint will take all the fore/aft "slop" out of the arms (that's what's causing your wheel hop) while allowing a much more free movement of the suspension in all the directions that it's supposed to move. I'm running Spohn pieces on my car.

Bear
 

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There are no-hop brackets that attach to the diff housing at the center section and they are undetectable when the car is sitting on the road. They have been around for decades, and they work great with a stock suspension. They are not traction bars or ladder bars, merely brackets that keep the diff from winding up and changing the pinion angle on hard acceleration. I would go with those, or Air Lift air bags. Cheap and easy, if all you need is to stop wheel hop but don't want to modify the suspension.
 

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Every car is going to react differently, so it's going to take a little trial and error to find your car's happy place. I'd start with the minimum pressure on both sides (as per the bag manufacturer's specs), then add a little at a time. It might take some stagger (more air in the driver's side). And, there's always a chance the bags won't completely solve the problem. If you're control arm bushings are worn/loose that can cause the problem too.
Sometimes you'll get hop even with new bushings if they're the rubber ones and your car is trying to hook/is making good power. If that's the case, then the only real solution (in my opinion) is different control arms with some type of fully articulating spherical ends. Stiff poly bushings will probably cure the hop with factory arms but they also introduce other problems you don't want.

Bear
 

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Discussion Starter #13
Again you came through for me Bear. I will follow your directions and see what happens. I did have the car on the lift the weekend and noticed the bushings were original with 85k miles and have seen better days. Ill let you know how it turns out.


Sent from AutoGuide.com App
 

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Again you came through for me Bear. I will follow your directions and see what happens. I did have the car on the lift the weekend and noticed the bushings were original with 85k miles and have seen better days. Ill let you know how it turns out.
If that's the case, then I'd recommend you replace them with new rubber ones before you do anything else (or if you're up for some *significant* improvement in all regimes of operation, replace all 4 control arms with some adjustable ones with sphereical ends). You might just find that new rubber bushings will cure the wheel hop.

Bear
 

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X2. The hot tip seems to be about 5-8 psi on the driver's side and 12-15 psi on the passenger side to compensate for torque shift/load.
 

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Interesting subject guys. Have been watching this thread to see where it goes. I too have a similar problem but not exactly. On acceleration I get a snap, snap from the rear on the drivers side, loud enough to hear from inside the car. I looked under the old girl and everything seems tight. My under carriage looks the same as the picture post previous to this post, only I have air shocks, not bags. New sway bars, springs with 3:73posi. Running 275/60/ 15 on 8" rims, plenty of meat on the ground.
The question is, when I was looking to see what the snap was, I put a breaker and socket on a wheel stud and moved the car forward and backward, to see if the U joint was getting bad and that's when I saw the rear end ( pinion and U joint move up and down about an inch. Should there be that much play or travel in the rear end? Bushings getting bad in the control arms for the snap? But I never seen where the pinion would travel that much. It's like the whole rear end pivots/ twists down and up in reverse. Any suggestions?
 

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Have the solution atleast to my problem. Control arm bushing are all shot, especially the top ones.
Thanks for all the info guys in this tread. Helps everyone out that has or may have the problem come up in their ride.
 
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