Hey fellas,

I recently attempted my first pull in Trinidad CO, on June 10th. I did pretty good except for the bouncing of the truck. I had my 33" Ground Hawgs inflated to 20 PSI. Stock 3/4 ton springs in back with a 4" block. Corporate 14 bolt rear with 456 gears and a spool. Dana 60 front with same gears and 4" procomp springs. I had plenty of power throught the pull but lost alot of footage due to the bouncing. I'm running a 454 with rectangle port heads and 10.5:1 compression, with a 4 speed and a NP 205. Is my problem in the springs? Or could it be not enough shock?


Thanks for your reply,


A..........

My truck bounces real bad and I can't figure it out. Uknow some of the pro-stock aren't much more than what you got and myself included. Some of the pro-stock trucks front suspensions are all wore out farm and construction trucks just like mine and probably yours too. Those trucks go down the track like there on a cement hiway. Some have shocks, some have double shocks, everyone of them have different air pressures. I'm beginning to think it just can't be fixed. Every year about mid-winter I start wanting a new pull truck thinking this one won't bounce. Is your truck short wheel base? Mine is about 10" shorter than everyone elses(maybe that could be a problem). By the way, If you make it to Mitchell Ne. I will probably see you there. Unless my clutch goes out. I am going to a pull in New Castle Wyoming Fri. night and I'll know after that.

Are you using ladder bars? I fabricated the ladder bars for the rear axle, that extend up to the back of the cab. On the front end, I went with dual gas charged shocks on each corner. Also, I ran 55psi in the rear tires and 45 in the front. With this setup, I only bounced once last season, and that was because the track was wet from a misting rain all day. They skimmed off the top layer but apparently the grader operator didn't think anyone would make it to the 300' mark, so he didn't work that end as well, and that's where I bounced. (still won the class though).
Also, last season, we weren't allowed to use a weight bracket out front, so I had a lead filled OEM front bumper and 300lbs in the cab.

My Daddy always told me if your bouncing your not pulling ..You Have to get that puppy to lay down and go...

So here's my 2Cents......

Put 35 # of air in the rear tires .. and drop the front tire pressure to 13 #...
Everyone well tell ya you have a flat .. but don't' worry they should stay on the beads.

By the way have you ever tried to bounce a flat basketball..

Oops that was about a dimes worth...


Send me the change from your first win at the next pull....

ShaZam

First I want to say I am in no way a Pro at this. But it is in my experience. A truck will benefit alot by running as soft as possible springs in the front with as little upper arch as possible. In other word try to change springs to the point that they will just hold up the front and what weights you may add if any. Some guys here even change to coil springs in the front. Hope this helps good luck.

we've had the best luck running soft springs in front and very stiff springs in the rear, to the point they really don't move at all (didn't squat the truck with 8,000+ lbs in the rear, although thats probably not the safest test). ladder bars have also helped tremendously, but around here some places don't allow them. we also run 20 to 30 psi in the front tires and anywhere from 40 to 75 in the rear, running the higher pressures with nearly worn out tires, and the lower with brand new tires. Also if you are not running ladder/traction bars in the rear, those 4 inch blocks probably are making it worse, as they allow the axle to put more torque on the springs, causing more axle wrap. Every truck is different so this may or may not work for you, just my $.02.

I have ladder bars in the rear welded to the axle with suspension blocks.18 lbs pressure in the front tires. I watch videos of my truck and it is definately bouncing in the front.

We also run bars in the front, only off of the bottom side being as there is limited room on the top of the axle. Our front springs are set so that the truck sits level as it is pulling, with I believe only two or three leaf springs per side, so that it sits on the bump stops. The truck sits low in the front when parked, almost like a older two wheel drive 3/4 or 1 ton truck, but stays almost perfectly level when hooked. Our front springs also have enough down-travel that the truck can be lifted up 7+ inches before the front tires leave the ground.

From what I've learned from all you animals...this is what I'm gonna do for Springer NM:

- Instead of 22 psi all around, 30 in the rear and 15 in front.
- Getting rid of lift blocks in rear replacing with lift springs.
- Replacing all shocks with good quality stiff shocks.
- Adding another plate in front to get right at 6200#.
- Try to find a way to get headers on my engine.(no room)

I tried like hell to get ladder bars in the front but just no room with headers,steering shocks.

I don't know what your truck is, but in my 90 F250, I couldn't find off the shelf outside the frame headers, so I put in a set of Hooker supercomps last year. Knowing I needed larger tubes for the motor this year, I did some checking around and found a drag racer not too far away that will make headers to your specs. I'm wishing I would have checked into this last year because now I've got the supercomps sitting in the barn that I gave $400+ for last year and he charged me $690 complete for a set of custom fitted outside the frame headers.

The moral of this story is ask around to see if you can get a custom set made, you'll be money ahead in the long run.

Thanks man....I've got a BBC in a 69 3/4 ton. My motor mounts are custom, and I have very little room from head to block (1/4"). Also I have power brakes, clutch linkage, and heater core shroud to deal with!!!!! I think custom is going to be my only option.

Look at the Stahls. They are in a kit so you still need to build them but they are designed to work with your year of truck. It took us a about 3-4 hrs to get both sides done on the truck. Ours is a 79 frame with an 85 cab on it. Turned out very nice and clean.

Here is a link

http://www.stahlheaders.com/Frame%20New%20TT.htm