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View Full Version : Dropping BOTH right side bars one hole on the frame, what would the effect be?



hpmaster
07-12-2013, 12:49 PM
When would you do this? Are they not both sorta opposite in effect? Has anyone done this and when?

MasterSbilt_Racer
07-12-2013, 02:33 PM
When would you do this? Are they not both sorta opposite in effect? Has anyone done this and when?

Assuming 4 link with rr spring on front of cage:

Both remove steer. Lowering lower increases wheel rate. Lowering upper decreases wheel rate. Both decrease thrust loading of rr tire.

I have done either or both at the same time.

rubbinsracin
07-12-2013, 03:59 PM
lowering both bars should tighten exit. the have opposite effects on entry.

money17
07-13-2013, 01:24 AM
drop lower rr bar tighten entry and middle
drop upper rr bar tighten middle and exit

right?

hpmaster
07-13-2013, 08:49 AM
Out of curiosity last night and a bad draw in the feature, dead last, I did drop both right side bars, yes it is 4 link with rr spring on front of cage. Car was good in, ok in the middle, slightly loose out before dropping bars. In my car it did not effect entry to any great amount but tightened middle and exit on a dry slick track that was rough. Car was good as long as I did not try to pinch it down too hard on exit, loss some side bite. Also wanted to pick the left front slightly out, 2 or 3 inches acording to the guys helping me. Overall something to work with I think.

Dragoon55
07-13-2013, 10:52 AM
Out of curiosity last night and a bad draw in the feature, dead last, I did drop both right side bars, yes it is 4 link with rr spring on front of cage. Car was good in, ok in the middle, slightly loose out before dropping bars. In my car it did not effect entry to any great amount but tightened middle and exit on a dry slick track that was rough. Car was good as long as I did not try to pinch it down too hard on exit, loss some side bite. Also wanted to pick the left front slightly out, 2 or 3 inches acording to the guys helping me. Overall something to work with I think. Exactly what I expected. The reduced thrust angle and reduced indexing of spring is why the car wanted to lift LF. You also had less rear steer in the RR which tightened your middle and exit. Essentially it let the LR be more dominant and RR be more submissive. With less wheelbase change in the RR it handles bumps better too.

racedad17
07-21-2013, 08:37 PM
Out of curiosity last night and a bad draw in the feature, dead last, I did drop both right side bars, yes it is 4 link with rr spring on front of cage. Car was good in, ok in the middle, slightly loose out before dropping bars. In my car it did not effect entry to any great amount but tightened middle and exit on a dry slick track that was rough. Car was good as long as I did not try to pinch it down too hard on exit, loss some side bite. Also wanted to pick the left front slightly out, 2 or 3 inches acording to the guys helping me. Overall something to work with I think.

now with the above adjustments you made, how or what would you do to regain the side bite that you lost without moving those bars or is that possible.

hpmaster
07-23-2013, 10:40 AM
I am going to raise the Jbar one inch on the frame side this week leaving all the bars where they are at.

setup479point2
07-23-2013, 11:54 AM
now with the above adjustments you made, how or what would you do to regain the side bite that you lost without moving those bars or is that possible. Raise some weight or take a little LS% out

racedad17
07-23-2013, 10:10 PM
Raise some weight or take a little LS% out

was going to do this for next race, (raise weight) and was thinking about lowering lr bottom bar one hole, was needing alittle more drive off.

racedad17
07-23-2013, 10:16 PM
was going to do this for next race, (raise weight) and was thinking about lowering lr bottom bar one hole, was needing alittle more drive off.


I am going to raise the Jbar one inch on the frame side this week leaving all the bars where they are at.

let me know how this works for you, i wont be racing this weekend but was going to raise ballast and lower lr lower bar one hole to help with alittle extra drive off

7uptruckracer
07-24-2013, 07:15 AM
I'd raise the Left Upper for more drive off unless your whole corner is getting progressively looser throughout the corner then I'd drop the LL

racedad17
07-24-2013, 08:54 PM
I'd raise the Left Upper for more drive off unless your whole corner is getting progressively looser throughout the corner then I'd drop the LL

track has been dry slick top to bottom from entry turn 1 to entry turn 1

hpmaster
07-25-2013, 08:31 AM
As for weight in the car 16 gal. fuel cell is against the decking and forward to axle centerline. Weight is all on top rails inside of wheelbase and track, 44 lbs, except for one 30lb piece 22 inch up from ground just in front of RR wheel.