I have a 95 Rayburn swing arm under slung car can't seem to get any forward drive. Scale numbers are 54.8 cross 54.8 left and 57.3 rear it has a 400 LR and 350 rr any one got any suggestions?
Printable View
I have a 95 Rayburn swing arm under slung car can't seem to get any forward drive. Scale numbers are 54.8 cross 54.8 left and 57.3 rear it has a 400 LR and 350 rr any one got any suggestions?
Replaced pullbar spring lately?
No I haven't had it apart few weeks ago just looking at it didn't seem broke then but stiff as o board. I believe it probly came new on the car in 95 because when I called the other company's like winters for rear end parts and gave them the serial numbers they told me of was sold to CJ rayburn in 1995 and same with the rack
Those things don't last very long.
you def need to change the spring, it actually needs to be changed every few races, i think we changed them every 6 races if we went any longer we could start to notice a difference in the car. someone can post a link to the best place to get them, its been a few yrs since we had a rayburn an cant remember where we got them.
thanks, 4bangerhotrod
OK thanks its like 2 inch in diameter and 4 inch long
mcmastercarr.com High-Performance Chrome-Silicon Steel Die Spring
On my old Rayburn we ran 450 lf 525 rf 400 lr 375 rr as our best dry slick sprng set up. The rear bar adjustments were all the way down on the left and all the way up on the right. Your percentages look ok but we ran alot of bite, over 300lbs, which gave us a high cross weight and I found that how much the rr was moved back also influenced drive off, more was better, to a point. Like everything, others will disagree, like CJ, but that car was fast when set like that on the slick.
new pull bar spring for sure. then if you still are lacking, move it towards drivers side (both pinion and frame).
no the rails are in the same spot on the lr i made that rail not so thick so the axle dosent hit it i was told to do that by billetbirdcage i believe and its a 1995 year lm chassis not a modified chassis
500 in the front i think never had them checked though and 350 in the rr and 400 in the lr
dont you thing that might be something important to know what springs you have in the front end of the car
You really need to, "Know" what your springs are... I know your new, but this is very important. A common mistake newbies make(and some veterans) is trying to fix the turn exit first, when the handling problem started much earlier. For example if your car is tight on entry and your braking it loose, you'll never get it to hookup like you want on exit. Also if your throttle tight thru the center you could get what's called a, "Push/Loose" condition and spin the tires on exit. What happens is you throttle up, have too much traction and the nose pushes. Next you crank in more wheel to try and turn the car until the frontend finally grips, snapping the rear loose and spinning off the corner. None of these may be your problem, but since your new I thought I'd share some experience.
The first rule of chassis tuning is, first fix entry, then fix the center and finally fix the exit.
is there any way to tell what the spring rates are with out gettin them checked? because i have no spring rate tester
You can get close to what a spring is using the formula on dirt forum tool box, http://www.thedirtforum.com/toolbox.htm
but it is best to get them checked as switching spring rates is real big in making a car run well, in both turning and drive off. Always adjust entry first, if you can't get in a turn you can't get out well.
Also drive off is affected by frt springs more than you think. As weight rotates to the frt right on braking and turning the weight goes past the left frt spring, the heavier the left frt spring is the less weight that ever gets to right front. Then on acceleration the right frt spring pushes the frt end up again, sending the weight back to the rear right and then to the left rear. So if the right rear is too heavy it stops the weight on the right rear before it gets back to the left rear or if the right rear is too soft the weight goes past the right rear not getting the drive on that wheel it should have.
Remember the heavy spring gets the weight. This weight rotation, it's speed or timing and amount is affected directly by spring weight.
Having raced Rayburns and won with them adjust the car more by what the car is doing than the book settings or what your competitors are saying, CJ's tunning tips is all you need, just don't get all hung up on what is working versus what the book says for bite, springs and weight percentages. Then when the car is fast weigh and measure the car for your records.
Earlier in this thread I pretty much gave you a setup I won with for a Rayburn swing arm, you don't believe it or want to try it thats your choice. JMHO.
We dont run Rayburns anymore, but we've won a ton of races running the same setup whether the track was heavy or slick. You can try this setup if you want, its been really successful for us in Georgia, Florida, and the Carolina's.
RF 500
LF 550
RR 300
LR 350
Purple Bar 5.5 on frame
Pullbar .5 left of center REPLACE SPRING
54.5 left
55.5 Rear
235 lbs bite (dont worry about cross)
Make sure you have a 1" and 2" wheel spacer, when track slicks off put 2" on LR and 1" on RF, put 4 rounds in left side and take 2 rounds out of right side. You shouldnt have to get too crazy with the bars, iv'e never been in the top or bottom hole on either side. If you have the old weld in bungs, make sure you put an extra bung between the "money hole" and the second hole on the LR. Thats way too large of a difference when adjusting.
Thats about what we ran as well, though we weren't as drastic with the spacers (1" LR), and we probably should have had that much. The main difference is we ran short straight left side panhard, and Z RR. had swing a long time and Z was more smooth, worked well on paperclip track.