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jsf74
07-12-2014, 03:21 AM
Im looking to tighten my car up a bit more for the feature and am wondering what adjustment would make the bigger change.

Change rr rim from a 3" offset to a 4" or move my rr top z link bar up one hole on chassis?

Currently I switch rr from a 2" to a 3", 1lb less air pressure in rr, fill with fuel and move rr top z link bar up 1 hole.

js11
07-12-2014, 10:35 AM
Is this a mid corner, corner entry, corner exit or ALL ABOVE problem. If all around, do a small change and make a drive adjustment. Ultimately, it depends on your chassis (e.g., is it 4-bar 4-bar, or 4-bar-Z link, etc), your springs, the track, etc. The offset change you described has worked for me in the past.

Also changing brake Bias for more front brake (helps entry) and your driving style will also help if the track slows down dramatically. Keep in mind when you put the 4" offset on the RR, you gain a bit of side bite off the gas, but could make you looser coming out. You cold also try putting a turn on the LF and RR corners and Taking them off the RF and LR corners (most affects middle corner and exit). I tend to shy away from radical bar changes on the R side except for the lower bars. Try less angle on the RR lower bar (if 4 bar) if your track is not too tight in the corners. Not too much though. Be incremental and most of all, make a driving adjustment. If you feel comfortable doing this, go to a higher gear ration to get into your motor's power band quicker and help turn the car going in (soft peddle it).

Good luck.

js11
07-12-2014, 10:38 AM
Good post. Is this a mid corner, corner entry, corner exit or ALL ABOVE problem? If all around, do a small change and make a driver adjustment. Ultimately, it depends on your chassis (e.g., is it 4-bar 4-bar, or 4-bar-Z link, etc), your springs, the track, etc. The offset change you described has worked for me in the past.

Also changing brake Bias for more front brake (helps entry). Keep in mind when you put the 4" offset on the RR, you gain a bit of side bite off the gas, but could make you looser coming out. You cold also try putting a turn on the LF and RR corners and Taking them off the RF and LR corners (most affects middle corner and exit). I tend to shy away from radical bar changes on the R side except for the lower bars. Try less angle on the RR lower bar (if 4 bar) if your track is not too tight in the corners. Not too much though. Be incremental and most of all, make a driving adjustment. If you feel comfortable doing this, go to a higher gear ratio to get into your motor's power band quicker and help turn the car going in (soft peddle it). There are some other guys on here that can turn you onto some shock changes that could help also (not my strong point). Thanks for posting the question.

Good luck.

jsf74
07-12-2014, 12:36 PM
car is a 2010 lightning. lr clamped rr z link. the heats its fine but the biggest problem in the feature is the car just feels like its not underneath me if that makes sense. on entry as soon as i touch the brakes it wants to swap ends so corner speed has to be a lot slower. pretty good drive off but im loosing all my momentum on entry. i have 22 turns front to back and start at 8 off rear and add 4 more for the feature. seems like the more front brake i add the worse my problem WOULD get? its a top 10 car with a best of 3rd this year but its just not there for some reason. how many turns past center is normal.

powerslide
07-12-2014, 01:13 PM
Do you have brake gauges to confirm pressures front/rear?

jsf74
07-12-2014, 01:31 PM
no just did a static test in the shop.

jsf74
07-12-2014, 01:48 PM
thought that too jeff but no its going the right way.

powerslide
07-12-2014, 05:04 PM
My understanding is whichever master it's going towards is gaining pressure. I've never had gauges and was cranking it the wrong way for awhile

langdonracing48
07-14-2014, 04:20 AM
Are you running with the right front brake shut off? Is the brake line in good shape?

JustAddDirt
07-14-2014, 08:06 AM
Do what Lightning Chassis set up sheet tells you to do.