New Guy Needs Help !
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New Guy Needs Help !
Hello everyone
I've been reading the forum for some time now and finally have some questions for some real racers. I've been helping my brother with his truck this spring and we're having some major wheel hop issues. Its a 1949 chevy with a chassis engineering 3 link back half with a late 70s nova front clip. It weighs 2850 with driver and 1700 front and 1150 in the rear. It has single adj. coil overs with 110 lb springs. The wheel hop is so bad that it broke both axles a couple weeks ago. The only thing that seems to help is loosening the rear springs and raising the tire pressure. I don't think the spring pressure is perfect but it should be close. The slicks are kinda old but would this cause wheel hop? Tonight we played with the shock settings with no real results. I think the tire pressure is just a bandaid fix for something else. Anyone have any ideas?? Thanks
I've been reading the forum for some time now and finally have some questions for some real racers. I've been helping my brother with his truck this spring and we're having some major wheel hop issues. Its a 1949 chevy with a chassis engineering 3 link back half with a late 70s nova front clip. It weighs 2850 with driver and 1700 front and 1150 in the rear. It has single adj. coil overs with 110 lb springs. The wheel hop is so bad that it broke both axles a couple weeks ago. The only thing that seems to help is loosening the rear springs and raising the tire pressure. I don't think the spring pressure is perfect but it should be close. The slicks are kinda old but would this cause wheel hop? Tonight we played with the shock settings with no real results. I think the tire pressure is just a bandaid fix for something else. Anyone have any ideas?? Thanks
- John_Heard
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Adding air pressure is probably just band-aiding the problem. The first two things I would sugguest is a fresh set of slicks and some good video of what the truck is doing at launch so you can watch it in slow motion.
My 1971 X275 Nova | Facebook
Well we tried a new set of tires today with the same results. After looking at some video the truck looks like it wants to bite then unhooks. It also looks like it squats alot more on take off than we thought so we looked at the shocks and the drivers side is bottoming out. My question now is shouldn't the suspension be working the other way and would moving the front of the ladder bar to another hole help plant the tires harder? The mount has five holes and were in the middle now. The bars are almost paralel with the ground. Any help woud be appreciated!!
- John_Heard
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If you want to extend the shocks more at launch, you'll need more anti-squat, since you have laddar bars this will be easy to try. Just move the front up a hole or two, that should shorten he instant center and make it plant the tire harder at launch. Give that a shot. At least you know now that the old tires are most likely not the issue. Do you have a way to post the video that you took?
My 1971 X275 Nova | Facebook
- jones_performance
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We got to take the truck back to the track again this weekend. We moved the bars from the middle hole to the top hole skipping one. We now have to much separation and are running out of shock travel on extension. I guess we moved the instant center to far back. We're going to try the hole we skipped and maybe figure out a way to put some weight in the back. This is getting old real quick!
- John_Heard
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It'll be worth it when you get it all figured out. You may end up needing shocks with a stiffer valving on the rebound/extension.
My 1971 X275 Nova | Facebook
- Mike Peters
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- Location: Wichita, KS
Just a few thoughts here.........first of all Chassis Engineering shocks are not good. I think you've already proven this to yourselves with statements the shock looks like it bottoms out. Sounds to me that the shocks can't control the violence of the launch of your truck. I would set the ladder bars back to the hole which is parallel at ride height. Spring pressure really doesn't have anything to do with launch other than setting vehicle ride height. If your springs are too weak, you can be using up shock travel trying to compensate for a spring that needs help holding the vehicle to the desired ride height. If the spring is too stiff, it can fight the shock valving. I would say I'd like to know how much power you're trying to put to the track as a high horsepower vehicle chassis set-up is not the same. Until you can control the reason the truck is hooking and then unloading, trying to plant the tires harder by changing suspension geometry is not going to solve your problem. Moving ladder bars or other suspension links changes so many things and is not as simple as unbolting and moving them to the next hole. So many things need to be checked but, I would say buying a good set of shocks would be the first step. Hey, you haven't even discussed the front suspension. I've seen cars unload the back tires when the front suspension tops out. If the truck is initially hooking and then unloading as you described, you need to track down the reason for the unloading and not looking to try to dial even more bite into the chassis. Just so many things it could be........
- Mike Peters
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