I need help with my bounce issue

[getblown5.9]

There is a local guy that pulls with us in Pa a lot that has a pretty stout 7.3 that would hop the front end real bad, always had that front axle chatter. He tried many things, tractions bars, tires, more weight, less weight, and the solution to his problem was a dual shock kit for the front end with some quality shocks to help keep the front end planted.


Also for some reason the extended cab fords just have something about them that makes them bounce bad. I dunno if its an issue with the frame or suspension geometry that creates a harmonic bounce thats impossible to drive out of or what but I know of quite a few of them that have bad bouncing issues.

Also what brand tires are you running? The guys that were running a bigger more aggressive tire had problems with it having too much traction off the line. Less traction and get the tires spinning quick so they cant squat, bite and wrinkle and start to bounce.

 

[bubba2400]

Need to put more angle on the hitch and get it closer to the top of the frame. Way too much leverage that far above the frame. Just two leafs in the front is all you need along with a good set of gas charged shocks, not oil filled! Good luck with it, hope you get it smoothed out.

 

[SEOHPowerstroke]

Thanks alot guys, I've cut the hitch out and I'm moving it back and at frame level. I'm also doing what I mentioned earlier to the front suspension like Ben Miller has. I hope to finally have this ironed out.

BTW, I have 35 inch BFG All Terrains, I ran 25 psi in the front and 50 psi in the rear, does that need any attention? Thanks

 

[mech2161]

What gear ratio, automatic?

 

[cummins724]

Thanks alot guys, I've cut the hitch out and I'm moving it back and at frame level. I'm also doing what I mentioned earlier to the front suspension like Ben Miller has. I hope to finally have this ironed out.

BTW, I have 35 inch BFG All Terrains, I ran 25 psi in the front and 50 psi in the rear, does that need any attention? Thanks

I had a bad bouncing issue & was running 50psi in my 33 bfg a/t. I checked my pressure before pulling Saturday night & noticed that my lh rear tire only had 45psi rather than 50. I aired up to 60psi in the rear & no bounce. I also lowered my hitch before the pull to 24 from 26...not sure which was the problem.

 

[bubba2400]

Thanks alot guys, I've cut the hitch out and I'm moving it back and at frame level. I'm also doing what I mentioned earlier to the front suspension like Ben Miller has. I hope to finally have this ironed out.

BTW, I have 35 inch BFG All Terrains, I ran 25 psi in the front and 50 psi in the rear, does that need any attention? Thanks

That sounds like it should take care of the suspension and hitch issues. Try to keep that hitch in line with the chain when it is hooked and tight.

Those tire pressures should be a good start without giving you any problems.

 

[SEOHPowerstroke]

What gear ratio, automatic?

My gear ratio's are a big problem right now, I'm running 4:10's with a manual NV4500. I run 4th low, or 5th low if the track is loose.

I plan to go to 6:20's this winter when I go to a Rockwell and drop box/reverser. These fast gears are too rough on drive line parts.

 

[RyanB]

Personally I also don't see the reason to go with coil-overs. From what I have seen 99% of all wheel hop is either because of shocks or tires. I had some crazy wheel hop (alsmost more of a chatter) that would go right thru the drive train and you could the effects of it in the engine from loading and unloading. Check out this video.... YouTube - Orangeville Truck Pull 07

I then added a pair of 90/10 competition engineering drag shocks (recomended to me by Van Haisley) and it solved all the problems. What happened then after realeasing the clutch the whole front end of the truck would lift up and then slowly settle back down going down the track. The 90/10's are 90% harder to compress than to extend and this works in taking out that bounce and chatter.

Here is anotouher video after they were on...not the best as its in the dark but you get the idea.

YouTube - Fergus Fall Fair Sled Pull

RyanB

 

[house]

get rid of the front lift! my truck hopped till went back to factory leafs in front and all quit

 

[6.0superduty]

i disagree 100% for one its not legal in any class rules and secondly you wanna pull down on your rear end and let your traction bars distribute your weight to the front and pull up on the front of the truck and then have the weight on the front do their job, out of all the pulling trucks my buddy has built taking the hitch up that far to the front of the truck has NEVER worked for us, not saying it wont for someone else but i watched it last night and the truck is bouncing like a basketball because its preloading the rear end and everything is too tight need some give. Just my opinion.

If its not legal, how was he doing it? Why would you want the front end to be lifted? Doesn't that defeat the whole purpose of having 4 wheel drive? In a perfect world, you want only a horizontal load on the hitch and nothing pulling down on the hitch and 100% of the trucks weight on the front axle. You want the hitch as close to the same angle as the chain as you can get it.

 

[SEOHPowerstroke]

Thanks Ryan, I will look into those shocks, they sound like a better idea. And I got rid of the lift House, it is bouncing like this on stock suspension with the rear shackle welded up.

 

[SEOHPowerstroke]

Just to clarify I pull in two circuits one being the Central Ohio Truck Pull Circuit and neither of them have any hitch rule other than stating that pull type hitches are allowed. I am running a pull type hitch.

 

[mech2161]

Thanks Ryan, I will look into those shocks, they sound like a better idea. And I got rid of the lift House, it is bouncing like this on stock suspension with the rear shackle welded up.

Setting the suspension up like a mod truck is ok if you have that kind of power. You need the suspension to be a soft as possible. If not it will transfer the energy to the frame. While the Ford frame is tough, it's also the most flexible. When you put the power to it on the line it stores energy. When the tires brake loose the energy is released. This is where the bounce begins. There are several way to go about stoping it. Spinning the tires sooner stores less energy in the frame. Making the frame stiffer will not allow it to store as much energy. It's finding the happy medium that's hard.

Watch the frame flex between the cab and the bed.

[MEDIA]http://www.youtube.com/watch?v=lJXY1QFDgxM&feature=channel_page[/MEDIA]

 

[smokin06]

If its not legal, how was he doing it? Why would you want the front end to be lifted? Doesn't that defeat the whole purpose of having 4 wheel drive? In a perfect world, you want only a horizontal load on the hitch and nothing pulling down on the hitch and 100% of the trucks weight on the front axle. You want the hitch as close to the same angle as the chain as you can get it.

because he pulls at all vannests pulls where they allow nitrous so anything goes and nobody even knows what they are looking at as far as hitchs heck they measure your turbo with a tape measure, anyways you make the truck as light as you can to put the most weight on the front so as the weight comes down on the back it distributes the weight to the front the sled will put the weight on the back for you. but his point is too far forward and its pulling up on the front of the truck and loading the rear and thats why its bouncing. if he pulls it back where its supposed to be it will distribute the weight better and not pull up on hte front of the truck.

 

[SEOHPowerstroke]

Here is the rear suspension setup that I have been running for the last 3 pulls since I bent and twisted the old bars that were pictured in earlier threads. Here is also a picture of the new stance of the truck. I went up in the rear to help transfer weight forward as well.

This is a very rigid setup now, the frame has no flex and I doubt it stores much energy as it is currently. I know that I am shy of Mod truck HP, but I think I'm definitely in a different league now than I was with my 700HP powerstroke that I had absolutely no suspension issues with. I would estimate my current HP rating between 1100 and 1200 to the ground.

 

[smokin06]

Just to clarify I pull in two circuits one being the Central Ohio Truck Pull Circuit and neither of them have any hitch rule other than stating that pull type hitches are allowed. I am running a pull type hitch.

ok then dont change it, try going to london or up to wilmington and pull see what happens we built a truck 3 years ago jsut the way you did with your hitch and couldnt pull at any big pulls. just trying to help, you stated in your build thread that you were only pulling at american farm pullers pulls and they didnt have a hitch rule, which they dont but its not legal anywhere that knows what they are looking at.

 

[smokin06]

Here is the rear suspension setup that I have been running for the last 3 pulls since I bent and twisted the old bars that were pictured in earlier threads. Here is also a picture of the new stance of the truck. I went up in the rear to help transfer weight forward as well.

This is a very rigid setup now, the frame has no flex and I doubt it stores much energy as it is currently. I know that I am shy of Mod truck HP, but I think I'm definitely in a different league now than I was with my 700HP powerstroke that I had absolutely no suspension issues with. I would estimate my current HP rating between 1100 and 1200 to the ground.

the truck looks good and definitely has the power, youll get it figured out, i plan on having my truck out for gallipolis, weston is helping me with it and its gonna be 1,000hp 12v. i am from pomeroy i work at mountaineer plant and worked with your dad he was there for luburgh.

 

[SEOHPowerstroke]

because he pulls at all vannests pulls where they allow nitrous so anything goes and nobody even knows what they are looking at as far as hitchs heck they measure your turbo with a tape measure, anyways you make the truck as light as you can to put the most weight on the front so as the weight comes down on the back it distributes the weight to the front the sled will put the weight on the back for you. but his point is too far forward and its pulling up on the front of the truck and loading the rear and thats why its bouncing. if he pulls it back where its supposed to be it will distribute the weight better and not pull up on hte front of the truck.

I agree with that post whole heartedly. I have been saying that since the third hook of the year, but everyone else was saying no. That is why earlier this evening I cut that big pain in my butt out of there and put it where it is supposed to be.

I just hope everything else works out this time.

I'm gonna wear the darn tow rig out before I put a full run on my motor:bang

 

[SEOHPowerstroke]

the truck looks good and definitely has the power, youll get it figured out, i plan on having my truck out for gallipolis, weston is helping me with it and its gonna be 1,000hp 12v. i am from pomeroy i work at mountaineer plant and worked with your dad he was there for luburgh.

I worked there over the summers when I was on break from college. I put all the liner in that darn hole. Then dumped all the money in this bouncy ball:kick:

 

[smokin06]

I agree with that post whole heartedly. I have been saying that since the third hook of the year, but everyone else was saying no. That is why earlier this evening I cut that big pain in my butt out of there and put it where it is supposed to be.

I just hope everything else works out this time.

I'm gonna wear the darn tow rig out before I put a full run on my motor:bang

if ya need any help pm me and ill give ya my number and i can help ya what i can, the guy that built your hitch argued with me at mineral wells i told him what i thought would work but he didnt listen i would love to see that thing run so if ya need any help let me know.