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latemodel22
12-20-2017, 09:40 PM
I feel like I need a better understanding of what happens when raising and/or lowering the car at each corner. IE: What happens if we raise the rr of the car up 1/4"? I understand the car gains weight on that corner and bite goes down and the car isn't going to travel downward to the same point now.

latemodel22
12-25-2017, 11:02 PM
Anyone care to chime in ?

CCHIEF
12-25-2017, 11:41 PM
Not sure what you are asking.....how handling will change??

MasterSbilt_Racer
12-26-2017, 08:29 AM
I feel like I need a better understanding of what happens when raising and/or lowering the car at each corner. IE: What happens if we raise the rr of the car up 1/4"? I understand the car gains weight on that corner and bite goes down and the car isn't going to travel downward to the same point now.

Assuming a simple single, linear spring, the car has more rr weight at all points on the track than before. It will also have more uphill bar angle. Biggest thing is looser exit with the change.

latemodel22
12-26-2017, 12:59 PM
I see. This is some of the info I was looking for. so it wont have much effect on entry? I would have imagined that it would have let the nose turn alittle better. So that brings me to the next question, what about the LF? obviously lowing that corner gives you the aero advantage but what else does it do?
Assuming a simple single, linear spring, the car has more rr weight at all points on the track than before. It will also have more uphill bar angle. Biggest thing is looser exit with the change.

latemodel22
12-26-2017, 01:01 PM
Yes, entry center and exit changes
Not sure what you are asking.....how handling will change??

MasterSbilt_Racer
12-26-2017, 01:07 PM
I see. This is some of the info I was looking for. so it wont have much effect on entry? I would have imagined that it would have let the nose turn alittle better. So that brings me to the next question, what about the LF? obviously lowing that corner gives you the aero advantage but what else does it do?

Bar angle loosens off gas entry. The weight tightens it. Doesn't seem to matter much in my experience. Wheel rate and steer seem to be king for entry adjustments.

LF changes get pretty tricky because car attitude and the track play a huge roll in what happens. Sometimes you are really on the lf spring on entry, sometimes you are not. Impossible to give a one answer fits all.

hucktyson
12-26-2017, 01:49 PM
To actually raise the RR a 1/4" it's going to take a decent amount of turns as you crank the adjuster down the further the spring compresses as it increases the load on that corner. If you are running at a track where you stay in the fuel in whole way around it will tighten entry for sure. I have no clue what it will do on a stomp and steer bullring as I avoid those places

latemodel22
01-08-2018, 05:45 PM
what I have noticed is our car/driver likes to trail the RR, 1/2" at a lot of times. If we do not, the car seems to be pushy on corner entry. I'm looking to get away from all that trail as it seems there is something we can do to rr spring to kinda sorta do the same thing. Any thoughts?

a25rjr
01-08-2018, 06:25 PM
what I have noticed is our car/driver likes to trail the RR, 1/2" at a lot of times. If we do not, the car seems to be pushy on corner entry. I'm looking to get away from all that trail as it seems there is something we can do to rr spring to kinda sorta do the same thing. Any thoughts?

I always liked to soften the lf spring for entry tightness. It doesn't seem to affect exit either.

You could soften the rr but thats a pretty major adj....imo

billetbirdcage
01-08-2018, 07:52 PM
what I have noticed is our car/driver likes to trail the RR, 1/2" at a lot of times. If we do not, the car seems to be pushy on corner entry. I'm looking to get away from all that trail as it seems there is something we can do to rr spring to kinda sorta do the same thing. Any thoughts?

If you constantly have to add trail to RR bars, then likely the rear end is too far left for your set up/car. Typically if guys are close to 3/4" of trail, Then I have them move the rear end 1/4" or so right and remove the trail and try that.

That's a very generic answer though.

LF spring is a viable option, but that depends on if or how much the LF is accepting weight. On a very round track, it may be so little, the change isn't very noticeable and other places where the LF accepts more weight or much more at one particular place on the track then that is where it's most noticeable. So LF spring can be very track sensitive and some places you can change it and see very little difference.

missile07
01-09-2018, 07:34 AM
Could you accomplish the same thing by spacing the RR tire out (either with a spacer or changing wheel offset) or bringing the LR wheel farther in?
I noticed this past weekend at the Ice bowl that Ronnie Johnson's Capital crate car had the LR wheel tucked in further than normal. I have also noticed a few local Xr-1's with a 1-inch spacer on the LR to start the night and then they remove it as the night progresses.

Kromulous
01-09-2018, 10:09 AM
He off the gas when it gets pushy, or is he trying to power slide it ? Whats the track and is it tacky?

One adjustment for smaller tracks that are heavy to start with is indexing the top bar on the RR birdcage down a hole. It will help you steer the car with the throttle, basically when you need to power slide the car thru the corner.

What about a heavier LR spring? Also how about the heavy LR set up, i hear that helps the car rotate, and loosens the car when you let out of the gas. Never run it, so i don't know. I have used the heavier LR spring at smaller tracks to loosen the rear of the car overall.