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JB1K
08-22-2011, 08:06 AM
Anyone know the “correct” RR upper shock mounting location / angle for an 01’ MasterSbilt (inboard / outboard, there are two mounts). Been fighting a tight in condition all year with the shock in the inboard location (puts the shock at more angle). Also how far from the rotor should the lower shock mount be (my info shows 7-3/8” for the LR, but nothing for the RR)? Any help would be appreciated.

ENVY Suspension
08-30-2011, 08:05 AM
Standing the shock up - moving outboard will help your tight condition. As for the RR measurement, im not positive of but to get it right, the 4-bar rods should be parallel to the bottom frame rail when the car is at ride height with the rear end set at the proper side to side measurement.

Kirk Loudy
ENVY Suspension

Dirt Man
08-30-2011, 12:08 PM
Standing the shock up - moving outboard will help your tight condition. As for the RR measurement, im not positive of but to get it right, the 4-bar rods should be parallel to the bottom frame rail when the car is at ride height with the rear end set at the proper side to side measurement.

Kirk Loudy
ENVY Suspension

I would like to hear your reasoning for that. We had an opposite condition where we were free getting in the corner. We spoke with our chassis dealer and he told us to stand it up and that made us a lot better!

JB1K
08-30-2011, 12:51 PM
Thanks for the replies guys. I tried this last week; seemed to do just the opposite of what I though it should - felt slightly tighter especially in the middle. Had to ust a lot of brake to get the car to turn. Any idea why?

Im going back to the inboard mount with other changes this week!

Matt49
08-30-2011, 03:11 PM
Standing the RR shock up will increase the wheel rate of the RR tire and decrease the roll rate of the rear end of the car.
So there is no silver bullet answer - it depends on the attitude of your car and a lot of other components of your setup.

MasterSbilt_Racer
08-30-2011, 03:59 PM
Thanks for the replies guys. I tried this last week; seemed to do just the opposite of what I though it should - felt slightly tighter especially in the middle. Had to ust a lot of brake to get the car to turn. Any idea why?

Im going back to the inboard mount with other changes this week!

If you were using the same spring, the wheel rate was increased initially, but it would be less progressive through roll. See Matt's post for a bit more info.

MasterSbilt_Racer
08-30-2011, 04:02 PM
There are effects to the "static" state of the suspension and dynamic effects. Sometimes one will be more dominant than the other depending on how the car is driven and the car's attitude.

Dirt Man
09-01-2011, 03:11 PM
Mr Envy, I would like to hear your explanation of your theroy.

Dirt Man
09-01-2011, 03:14 PM
Thanks for the replies guys. I tried this last week; seemed to do just the opposite of what I though it should - felt slightly tighter especially in the middle. Had to ust a lot of brake to get the car to turn. Any idea why?

Im going back to the inboard mount with other changes this week!

Just as I thought would happen for you. If you PM me your e-mail address I will get you in contact with our chassis dealer. He has been helping us out pretty much this year.

MasterSbilt_Racer
09-01-2011, 04:46 PM
If the two mounts are not the same height, that opens another can of worms as well.

JB1K
09-02-2011, 06:45 AM
My mounts are at slightly different heights, with the outboard one being lower. Between the two mounts it took almost 7 turns on the coil over nut to get the ride height back.

hucktyson
09-02-2011, 08:45 AM
Mr Envy, I would like to hear your explanation of your theroy.

Scott Bloomquist and Brian Birkhoffer would still be looking for there first win without having come in contact with the captain !!!! When you have those credentials you dont have to explain your self !!!!!!

Dirt Man
09-02-2011, 01:30 PM
I was not questioning his credentials Huck, I was wanting him to elaborate more on his theroy cause it certainly was opposite in our case! It's called education, I like to learn all I can.

C10
09-02-2011, 05:46 PM
Standing it up tightened the snot out of our car on entry. The idea I have on it is because the shock stays more upright putting more load on the rr instead of letting the rear rollover easily with the rr with angle in it. Then as well, as you stand it up, it makes the rr spring act like it is stiffer. BUT we did NOT run this tight when we ran a 250 to the now 225.

K15
09-03-2011, 08:50 AM
soften your spring 25lbs and try it again. there is a formula somewhere that u can figure your angle to keep the ride rate the same. basically more angle=more spring. less=less to keep the wheel rate the same