Compression travel on the rr!

[ZERO25]

On the straightaway, how much does the rr spring/shock compress?(from ride height)

[MasterSbilt_Racer]

On the straightaway, how much does the rr spring/shock compress?(from ride height)

Depends on track shape. Often it's extension.

[manwplan]

Depends on track shape. Often it's extension.

Yep and actual data would blow most people's minds. Often what you think happens is quite the opposite.

[ZERO25]

Depends on track shape. Often it's extension.

Ok, give me some parameters!

[MasterSbilt_Racer]

Ok, give me some parameters!

Until something stops it, unless you really tie it down with a shock. Anything from 1/4" compress to 1.25" extension is well with reason.

[ZERO25]

What do you think their goal should be? Wouldnt it help aero wise to get it down lower.

Some of the better cars at Eastbay were quite a bit lower. I saw a couple of rr springs that were put on before the features and they were very small.......i would say in the 150 range.

[MasterSbilt_Racer]

What do you think their goal should be? Wouldnt it help aero wise to get it down lower.

Some of the better cars at Eastbay were quite a bit lower. I saw a couple of rr springs that were put on before the features and they were very small.......i would say in the 150 range.

You get the rr too low, it kills aero. Air is going to get under the front. It could be because the rr tire was the only one that worked, due to compounds allowed. They were probably trying to get the car to turn off throttle.

[JustAddDirt]

Lift arms will Lift, until something stops it.(chain, heavy tie down shock...etc) Plus lift arm is on the right side of the rear end bell, which will try to plant the rr just a little harder because it is the closest tire to lift arm.
Then there is the J bar....
Also with the rotational direction of the gear set in a QC, it is trying to plant the RR harder as well.
Lots of things not thought about going on, with the RR of these cars.

[MasterSbilt_Racer]

Lift arms will Lift, until something stops it.(chain, heavy tie down shock...etc) Plus lift arm is on the right side of the rear end bell, which will try to plant the rr just a little harder because it is the closest tire to lift arm.
Then there is the J bar....
Also with the rotational direction of the gear set in a QC, it is trying to plant the RR harder as well.
Lots of things not thought about going on, with the RR of these cars.

With shorter lift arm lengths being the current trend, that has a bigger effect than it used to.

[hunterracing]

We won a few races several years ago with lift arm 30 inches on a 250 spring no bump

[ZERO25]

With shorter lift arm lengths being the current trend, that has a bigger effect than it used to.

History repeating itself?

Like the old Smack days......325 @ 32"! Thats what worked for us in the nlms days!

[CCHIEF]

You may find some 4" bump/helper springs on the rr to increase the extended load down the straight and maintain compression load. Without DA who knows on rr compression, personally I work with the 2" # and visually observed posture.

[MasterSbilt_Racer]

History repeating itself?

Like the old Smack days......325 @ 32"! Thats what worked for us in the nlms days!

I haven't done anything different on 5th coil since 1998. Tried stuff, but never found anything better.