soft lr spring

[riddle28]

ive been experimenting with a softer LR(125), when the track is fast the car is hard to beat, when it blows off it never gets the rr in the track. Hard to explain but what it feels like in my mind is instead of compressing the RR as the LR rebounds its just using the rr as a pole vault of sorts and rebounding the LR and not planting the rr. Shock travel is alot less now too. I havent changed anything else, same bite and ride heights. Are there any supplemental changes you need to make to go along with the soft LR?

[collateralDamage]

It sounds like you have too much preload.

[riddle28]

I’ve got what it takes to get my normal bite up

[collateralDamage]

I have used a bumpstop and packers to hold the left rear up if it droops too much. Just make sure you aren't racing on the bumpstop! There are other ways around it as well.

[garrett87]

Sounds like you are not driving in deep enough and keeping it up on the bars. We had the same problem with the softer left rear. I was told it was entering the corner and it was.

[billetbirdcage]

Like garrett said it can be driving or track style causing the issue.

First thing is you need know: Is the LR setting down more then before. If so then you need to look at driving or it may be due to a more paperclip style track where you off the gas and on the brakes while the car is still going in a straight line.

Figure out if the LR is in fact coming down more by asking crew guys (I know most of them are just watching the race and not really what the car is actually doing, lol.) or get some video unless you have data to look at.

After that you can decide where to look next or what to do to fix it, but since you lost RR travel I'm gonna guess the car is setting down more then it was before, but that might not be the case and that is where you need to start.

[riddle28]

I’m pretty good at trail breaking not setting the lr down, we can’t run bumps so I can’t do that anyways. I softened almost 100 lbs and i can feel the lr digging harder(more bar angle with increased droop) but feel like what I’ve gained on the lr I’ve lost on the rr

[mmarineservice]

Take some of the drop out of lr when it starts to slick off

[Jim11h]

We were just told by a chassis builder to basically run top lr rod in bottom hole and with full drop adjust bars so that birdcage is straight up & down. This same person also says he runs a 100# RR spring (gotta be bump I'm thinking). Says the soft lr & birdcage give drive in slick.

[MasterSbilt_Racer]

We were just told by a chassis builder to basically run top lr rod in bottom hole and with full drop adjust bars so that birdcage is straight up & down. This same person also says he runs a 100# RR spring (gotta be bump I'm thinking). Says the soft lr & birdcage give drive in slick.

100# rr or lr?

The birdcage deal is just a geometry problem. You get rid of anti-squat lock and bring compliance back to the system.

[CCHIEF]

Crate or true super late....what make make/model/year... or updated to? ,what springs are you running everywhere else. What do you change up when the track loosens up... if anything? What did you run in the LR previously...and why did you change up. Did the car handle well in low traction previously. "when it blows off it never gets the rr in the track" ...... so the car is loose on corner entry/decel/braking??? and therefore loose overall in slicker conditions

[riddle28]

steelhead, 09 bwrc, 350 rf 500 lf 250 rr and was on 225 lr before the swap, the only reason i swapped was to get some more hike and roll steer out of it which it does in the traction. We ran well at talladega all year last year, one of the slickest tracks in the south, loose from center off but steers in great. It just skates off the track and doesnt plant. No other changes ive made other than the spring, which is why i was wondering about supplemental changes before i swap back to i know what works and look elsewhere for speed

[CCHIEF]

No experience with BWRC, "loose from center off but steers in great." is this on your old deal or with the 125? So if you actually got more "hike and roll steer", the car will be looser, Steer gets excessive in the last inch of travel)Possibilities>>softer rf spring will load the rr more, don't know what you can get away with on those cars...Ive been as low as 250 rf on blue rockets on smooth momentum tracks with a 125 in the lr, and they recommend a 325 as a baseline, but they have the necessary ground clearance >> limit your drop to keep roll steer in check 1/4" @ a time if your beyond (more) than the recommended baseline, the baseline is usually a good compromise of steer vs dynamic wedge. Too much roll steer will kill a well balanced car. Your car will definitely roll up easier with the soft lr spring, you may need to increase lr compression to control hike down, hike down tightens the car and un loads the rear of the car... It's all about entry..... its all about entry...attitude and yaw, keeping chassis roll in the car as the track loses traction and keeping the rr loaded. Ideally your front wheels should stay as straight as possible thruout the corner, the car should need minimal steering input once initially steered into the corner, part of that is setup and alot of it is driver. If your swinging beyond 11 turn in to 3 o clock exit, your off in the slick...usually tight to loose just as you begin exit(indicates tight entry or excessive roll steer) you can lower your LR lower bar @ frame but that will tighten entry an tighten rolling the corner.but may work well for you. What you need from the car to keep the steering input to a minimum is what and where @ you need to relay to your crew(chief) or make mental notes of if your calling the shots. You make no changes as the track slows down to maintain roll in the car? Now and pre soft LR?

[fastford]

are you on a stacked LR or a single spring?

[tmo54]

Lengthen your left side rods and add a few rounds to the rr. That's what we do when adding droop to keep drive off