Loose, loose, and loose.

[ambonci21]

OK here we go. Got a 4/4 spring behing shock in front lr, spring in front shock behind rr, both on sliders. Chevlle front stub. 1/4 mile banked track always slick. Car is always loose no matter what we do. Cars loose in but driver likes it like that to a point, loose in the middle and spinning tires like crazy on exit. I'll try and give as much info as possible. Scale #sLf-497 Rf-485 Lr-705 Rr-606 Rear%-57.2 Cross%-51.8 Left side-52.3 All numbers are WITHOUT driver. Springs: lf-700 rf-800 Lr-200 rr-175 Shocks, bilsteins.Lf-30/50 rf30/50 Lr-30/50 rr-30/30 JBar 7 3/4 up on frame, bottom hole on pinion 9in. Pull bar bottom hole on frame- 18 degree of angle, can't remember off hand on spring rate, moved slightly to left on rearend .RR leading by 3/8 Tire pressures. Lf-8 rf-12 lr-8 rr-10 Lrb 27- 46 at full drop. Llb 3 Rru 12 Rlb 0 0Last night bottomed out lr shock in the heat, changed the rf spring to a 650 and scaled it at the track and went with 74lbs lr. The car was absolutely terrible, no drive off and looser then before. We won a month ago but since then we had been lacking forward bite. We won with a 650 lf 700 rf 225 lr 175 rr but car was still loose that night. We are pulling our hair out and tempted to go clamped up zlink. Hoping to get pointed in the right direction. Thanks guys.

[washeduptoo]

Have you tried higher up on frame with jbar? What offset on rr? How much shock travel on rf? Some things to consider, some like the jbar with little rake in it, others with a lot of rake in it. Try to get entry like he wants and go from there, a higher wt spring on lf usually helps. Is there a reason why your running rr shock behind?Best of luck

[dirtracr33]

springs r pretty stiff for chevelle...650 left, 600 right..175 lr, 200 rr...lotta lr w/o driver...might bump down to about 50 w/o driver...put shock and spring together on rr in front..

[ambonci21]

4in on rr. We had like 1.5" left on the right front shock for travel. It seems like the taller the spring is on lr the better the car is. Softer lr and rf springs will help the car rotate and have better traction? Are you saying to put the rr on a coilover? Thanks guys

[25drtrkr]

I really think ur having driver issues. I think hes over driving the entry. The dead give away is the 3/8 rr lead. That's a sure sign that the car is really too tight. If you don't think that's the case, make some big swings both ways. Sometimes you have to do that to figure whats really goin on.

[ambonci21]

I just checked the setup book and the rr is leading a 1/4 not 3/8. Sorry about the confusion. Shouldnt you trail the rr and lead the lr? Also the chasis is kinda old (07) and at ride height the lr axle tube only has 3.5" till it hits the underslung so we have a chain setup so it stops just before hitting the underslung bar.

[swartzman]

I'm not saying you have not checked this but make sure you do not have a a birdcage or anything binding the car up at all, take everything loose and check it all. you would be surprised how many times that has caught people..

[washeduptoo]

Most run the rr with a c/o set up in front with a 4link. Check your brake bias to see if he is using front or rear brake, if its rear, it could be too tight like was suggested earlier. You might can try the softer springs like was suggested earlier too. Best of luck

[ambonci21]

Will do. You guys are great by the way, glad I'm on this forum.

[DaveBauerSS6]

If you won a month ago,at the same track, with the same driver,why would you change to a z bar? Something in the car changed. Verify all the shocks are good, check for bind at all pivot points, front and rear.Put the car back to the setup one month ago as a baseline.
BTW after you find your way back, I would drop the front spring rate.

[ambonci21]

We didn't change to zlink. We had the same setup in the car as far as baseline till the other night. I agree something in the car changed but the track also changed quite a bet also for the worse as far as bite.

[Bcollins82]

the lr axle tube only has 3.5" till it hits the underslung so we have a chain setup so it stops just before hitting the underslung bar.

IMO, this is a lot of your issue up off the corner. Cut that underrail out and replace it with one that will clear about 5" of LR drop. Use an adjustable chain and I would set it between 4 and 4.5" to start. Reset your left upper angle so you are still at 45* with full droop. Then I would roll the RR back some. As others have said, it's probably way tight and the driver is breaking it loose to turn in causing it to skate and never scotch up. Another sign of that is the bottomed out LR shock you mention in your first post. If that happened under green obviously he's letting it slam down on entry. That will kill sidebite and make it loose on entry through center.

[ambonci21]

so today is race day and we will soon see what happens with our changes we made. we did soften up front springs as recommended, changed to lf 650, rf 600. we also put in a 16" lr 175 spring. we ran that spring last year but car at times would not turn, would just want to go straight. what we realized is that we were running so much preload in that spring that it was making the car super throttle tight, but the car had way better drive off with that spring, when we put it in the other night we now have very little preload in it. we also lowered lr bite to 50lbs recentered rear end, put all bars back to a neutral setting, also we found some signs of the pull bar binding, so we completely took it apart and cleaned everything. We are close to last years setup which we were faster with two wins and are back to a more baseline setup. we have double features tonight so we will be getting good track time. thanks for the help guys and good luck to all at the track this weekend.

[ambonci21]

well what a different car last night. the first feature the car was loose from middle off, but we were also high on RRU , LRL, and RRL. after that for the heat race we lowered LRL bar one hole and and the RLB bars one hole, won the heat convincingly but still tick loose off. come feature time we lowered the RRU bar two holes and added 1 turn into the LR spring slider. feature time the thing was spot on fast. after many any cautions we came home with another feature win. on a side note, still have 1" or so left of rf shock. anyways thanks for all the help. will keep posted if needing any more help.

[Reddy Powered]

Sounds like you got it figured out but I'd like to add. For anyone that's suddenly loose through middle and exit, take your axles out of the reared and look all the way through the housing to make sure it's not bent. I had a nightmare of a few weeks because of a bent housing. It was on the car when I bought it used.

[washeduptoo]

That's great, congrats, best of luck next race.

[ambonci21]

Dirt racer, we do run the shock behind on the rr. j bar rake is like 6" if I remember correctly 7 3/4 up on frame and bottom hole on the pinion. rr is still ahead of lr by 1/4", why do you ask? Just curious

[ambonci21]

RR spring is a 13" 175, shock is a bilstein 30/30. Not sure on slider angle, I will check it tomorrow. whats a good angle to be at running this setup. I do know that we are only getting 2-3" of shock travel on RR. I doesn't get on the RR that much. RR offset wheel is 4" this past week we won the track was used up slick little rubbered up and dusty. thanks. what are the benefits going to a coil over vs shock behind on the RR?

[ambonci21]

same shock as we run now? I hope to try it before the end of the season

[oldtrackchamp4x]

If you won your last race i would think about not changing anything. Make sure you write down exactly how car was setup that night, and track conditions. If you do decide to make a change you can put car back like it was. And don't be too concerned about how much you are compressing the rr as the track, according to you, was dry slick and dusty. JMO