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Cratedriver
11-13-2012, 10:41 AM
Recently we ran a little 1/4 gumbo track that was hard packed with 0 moisture. My standard 5th spring is a 325 mounted 35" out with 2 rounds of Preload, normal travel on semi slick is 3 inches.
In the heat race, running the bottom of the track, the spring traveled 1 3/4 " and the car felt like it was on top of the track with no forward off the turns. I went to a 300 with one round of Preload and it was better on initial throttle. I feel like I could have went as low as a 275 to get the rearend to load up without shocking the tires. Anyone agree/ disagree? I hear mixed thoughts on spring rates for the 5th coil, but my thoughts by watching the travel is the less travel wouldn't let the tires have the torque cushion to prevent them from breaking lose when rolling back on throttle. I should mention that I kept my lr spring at 225 when I should have went to maybe a 200 or 175. This is a pierce 2012chassis.

lovinlatemodels
11-13-2012, 06:27 PM
Try staying with the 325 just move the 5th spring closer to the rear being that short of a track you won't need to hold the traction long also you will increase travel closer to the rear if you at 35 i would move back 2 inches to 33 JMO

Cratedriver
11-13-2012, 10:28 PM
Thanks for the reply.
Another question I have is, on the torque arm with the car at ride height and pinion angle set, should the arm at the spring be level? Would it cause any negative effects if the arm was un-level like down hill?

dualdj1
11-14-2012, 07:05 AM
on the pierces, he's got a plate on the rear end that should be level at ride height. the angle of the torque arm and pinion angle is set by that.

we've found the soft LR helps (us) with forward and planting the LR on slick stop and go type tracks. haven't messed much with the 5th arm yet though, other than trying a little preload, so I'm curious what you find out here. had too many other issues last year to be able to try it.

Cratedriver
11-14-2012, 08:29 AM
Yes it does have the plate to set the pinion angleand with it set,the torque arm is below the chassis abt 2 inches ... I can adjust the heims and level it out, I was just wondering if there was any negative affects with it being at a down hill angle

lm#9
11-14-2012, 09:23 AM
on mine with plate level the torque arm is even with bottom of x

dualdj1
11-15-2012, 08:36 AM
Yes it does have the plate to set the pinion angleand with it set,the torque arm is below the chassis abt 2 inches ... I can adjust the heims and level it out, I was just wondering if there was any negative affects with it being at a down hill angle

really shouldn't make any noticeable difference, as long as you have enough 5th shock travel, etc. the only thing it can change is the angle of your 5th coil, and as long as that's mostly perpendicular, you should be fine. if you change the angle though just reset your coil preload/etc, and good to go

Cratedriver
11-15-2012, 10:18 AM
Thanks sir for the info... last night I check everything at ride height and the angle of the spring was way towards the front at the top... I should have already checked this ..... I have the spring mounted at 36 and the torque arm was 5° downhill which had the shock nearly extended all the way. I level the arm out and reset the pinion angle and it all looks quite better. Plus added the recommended Preload to the spring..... we will try it out next weekend at Swainsboro

dualdj1
11-15-2012, 12:51 PM
cool good luck. I think a little bit forward angle is normal/ok. let us know how it works out!