What are the affect of lowering or raising the j-bar are both ends equally?
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What are the affect of lowering or raising the j-bar are both ends equally?
changes roll center to a certain point higher or more rake will tighten car up and vice versa. higher roll center transfers more weight. this is all my findings, some others I'm sure will chime in. we made a 1/4 jabr adjustment this year(raised on chassis) and it made a difference (for the better) car seemed tighter getting in and through the middle.
To much j bar can make a loose on throttle feel. More drive off but unload rr. I've seen cars win on dry with 3" split and cars win with 11" split. Length is a factor too. I've seen 19" win and 22" win.
That is the least complicated way to adjust it. Generally speaking...Quote:
Originally Posted by nathan12
Higher at both ends will reduce chassis roll and loosen the car.
Lower at both ends will increase chassis roll and tighten the car.
You could get into a situation where perhaps the more steer from more roll out-weighed the tightness gained from less roll resistance.
mastersbilt_racer thank you that it was i was looking for.
ive been struggling in the slick and have been all over the car set up wise and have made jbar adjustments but mostly rack adjustments. was thinking i might need to move it as a whole rather then one end at a time
Have not chimed in on this for a while.... but something to keep in mind and maybe want to check at the shop. When you make the changes, you can shift the rear axle left to right or opposite. Just make sure your rear axle stays in the desired locations side to side when you adjust the j-bar. It's easy to assume it stays and you actually make a change there at the same time.
The past few years I've been leaving the J bar in one spot on the pinion and make slight adjustments on the frame side only (I typically never move it there either). I've found that it's one more thing that can get you dialed out of the ball park if you move the pinon side. Put it at pinion center for 9" or for QC 1 1/4" above the pinon, then work on the rest of the setup. JMO