I'm lost, need help badly

[washeduptoo]

At the start of the year, car was getting way too much pull bar travel, now it only gets 1 1/4in. Tried different pull bars, different springs and biscuits, still only 11/4. Tried brand new pull bar, still the same and its not rolling over on rf, got 3 1/2 shock left. Taken all springs, shocks and pull bar off and rear end rotates into tranny. Took all the springs/shocks off front and lowers move freely, uppers move freely, ball jts are good. Just don't know, need help. It makes no difference if track is heavy or slick, still same travel on pull bar and rf.Thanks

[powerslide]

At the start of the year, car was getting way too much pull bar travel, now it only gets 1 1/4in. Tried different pull bars, different springs and biscuits, still only 11/4. Tried brand new pull bar, still the same and its not rolling over on rf, got 3 1/2 shock left. Taken all springs, shocks and pull bar off and rear end rotates into tranny. Took all the springs/shocks off front and lowers move freely, uppers move freely, ball jts are good. Just don't know, need help. It makes no difference if track is heavy or slick, still same travel on pull bar and rf.Thanks

what brand of chassis?

[washeduptoo]

2012 Impressive, called him today and he provide me with some things to look at. If anyone else can provide any thing to look at, it would be appreciated. Trying to race this weekend. Thanks

[HRJ]

How much droop are you getting in your LR, are you running a wrap shock, and is your axle moved drastically to the left from baseline? What's the forward drive like? Driveshaft yoke isn't binding under load?

[xxxmod]

When i was looking at the impressive the pullbar seemed to high on the housing with to much angle at ride height,
High on the housing = less pullbar travel and under braking its trying to push the back of the car down and not pin
the right front.

[washeduptoo]

Will have to measure to see how high pull bar mount is. No dampner shock, lateral set to specs. 4.25 on drop, hardly any forward bite. When car had the rear end to the left about 1in more, it would pull the biscuits into. Not sure if I should move it back there as it had so much travel it broke the jbar and slung drive shaft and you know what other damaged happened. Thanks for the help. I can't run but every other week due to work and time is running out for the season.

[oldtrackchamp4x]

I had the same issue on dry slick. What i did was make the RF ride height 3/16 in lower than the LF, making sure my scale numbers stayed the same. I then put in two turns in LR and raised j-bar 1/2 in on frame side with pinion side 3/8 in below center. These changes were done after setting ride heights and off the scales These changes made a huge difference on my car getting it over on the RF. I have maybe 1/4 in of travel left on the RF shock, when before the changes i had 2 in left. I only get 1 1/4 in travel on my pull bar also but the car is fast. Can't comment on what to do on tacky, as i haven't had that problem. JMO

[powerslide]

Will have to measure to see how high pull bar mount is. No dampner shock, lateral set to specs. 4.25 on drop, hardly any forward bite. When car had the rear end to the left about 1in more, it would pull the biscuits into. Not sure if I should move it back there as it had so much travel it broke the jbar and slung drive shaft and you know what other damaged happened. Thanks for the help. I can't run but every other week due to work and time is running out for the season.

If it was too much of a good thing w/ an inch to the left maybe try 1/2in. I would't go much more than 1/2in either direction from the specs in most cases. Too many other adjustments to use. On the pullbar travel probably wouldnt worry about that either, 1 1/4inches isnt bad.

[HRJ]

When car had the rear end to the left about 1in more, it would pull the biscuits into. Not sure if I should move it back there as it had so much travel it broke the jbar and slung drive shaft and you know what other damaged happened. Thanks for the help. I can't run but every other week due to work and time is running out for the season.

When it slung the driveshaft, did it hurt the yoke or trans output shaft? Yoke/splines will act differently under load than up on jackstands in the shop.

[dlm82]

Do you have your pinion angle set correctly? Just a thought.

[washeduptoo]

Thanks for all the replies. I'll try to answer them in order. This is a QC if it makes a difference.

Oldtrackchamp, we talked tonight about if car doesn't get on rf, lowering the rf ride ht or it sounds like you raised the lf ht, sounds like that might work better?

Powerslide, I did move the rear end to left 1/4 inch tonight, to see if that helps also.

HRJ, as best I can tell with tranny in car, everything there is okay, drive shaft slides in easy(I really thought that was problem) when I started looking.

dlm82, I checked the pinion angle first, it was 8 degrees.

Things that might be problem is no preload in lr spring(got that fixed) and it appears the slider might have had too much play under load, it leaned a little in the middle toward one side(not centered in spring). Changed that out.

I got the old straight panhard out and taking it with me, I know it will bury that rf. Thanks again and will let everyone know how things work this weekend.

[BlackSlick2008]

Just an FYI... the older Bert trans has shorter splines on the input shaft. They fixed that in the newer ones. So running an 8" yoke would be pointless due to binding issues. If this were to be your problem then its fixable with a lathe. Have done many of them.

If your sure thats not the problem, I would rule out any suspension bind. Once you rule that out, focus on the RC's. Kind of like what OTC did when he moved J-Bar.

[washeduptoo]

Thanks blackslick for the information. Tranny about 2 yrs old and we do run the 8in yoke still thou. The weird thing is earlier in the year on slick tracks we didn't have this problem with pull bar or rf. I did last race move the jbar down on pinion, didn't really seem to help. Thanks again.

[washeduptoo]

XXXmod, I did check the pull bar ht and its 12in above center of axle tube. I guess its about ready except washing(again) and we'll give it a whirl tonight. I'll let know if its improved and again thanks to all for the help and suggestions.

[washeduptoo]

Well car wasn't any better on slick in heat. Haven't measured pull bar travel but it looks close to the same and not rolling onto rf, still had 3.5in of shock left in heat. Lowered the rf ride ht 2rds and put 2rds in lr and it was better for feature and 2.5in of shock left. I'm begining to think its too much jbar rake and going lower on frame for next race in a couple weeks if we get to run. It that doesn't work, going to lighter spring rf and it that doesn't work, going to increase lr drop. Anyway thats the update but we did move forward in feature,just got to keep working at it. Thanks

[oldtrackchamp4x]

What weight is RF spring? How much LR drop? Did you check your RF ride height to make sure it was 3/16 lower then the LF? Check it at the center of the front Aframe bolt before adding or taking out rounds. JMO

[washeduptoo]

Its all set to specs, rf is 600 spring. I didn't measure to see if its lower but will in the shop. It should be still higher than the lf. LR drop is 4 1/4.Thanks

[charcoal01]

If you took two rounds out of the rf and put two rounds into the left rear I think you actually took wedge out of the car. On my car if I take two out of the front I h e to put four rounds back into the left rear in order to come back to my numbers.

[washeduptoo]

Your probably right since the threads are different, but at this point, I'm not really concerned about the wedge, just getting the chassis over on the rf better. Only have 1-2 races at the most left and would like to know what helps for next year. Thanks for the help.

[xxxmod]

XXXmod, I did check the pull bar ht and its 12in above center of axle tube. I guess its about ready except washing(again) and we'll give it a whirl tonight. I'll let know if its improved and again thanks to all for the help and suggestions.

10 - 12 " above centerline should be right but IMO the pullbar angle should be 12 degrees at ride height.
J bars with a lot of rake generally pin the right front,do not exceed 6" difference between mounting points,move the whole thing down to promote roll
When looking at your car is the RR sticking out farther than the RF.... It shouldnt be