Since the camaroz28 forum never got any responses I'll do the honor of asking here.

What are the optimal settings for the Spohn torque arm and LCA bracket for drag racing. I know Steve reccomends 3-5 degrees down pinion angle on the torque arm but how do you determine the best position for the LCA. Everything on the web refers to traction bars and 4 links and trying to find the instant center of the vehicle but nothing is mentioned about third gen rear suspension.




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Stephen's racing page

87 IROC-Z Pro ET Bracket Race Car and knocking on the SuperPro ET class
383 stroker (carbed) with double hump cast iron heads and pump gas
Best ET on a time slip: 11.857
Best corrected ET: 11.163
Best MPH on a time slip: 117.87
Best corrected MPH: 126.10
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!

Member of the Calgary Drag Racing Association

 

-4 pinion angle on a car faster than 12.0.

LCAs on the lowest setting in the brackets is the best setting for drag racing.

On lowered cars that are set up for primary performance in AutoX/Road Racing applications, use the center setting on the bracket to put you back to OEM geometry. The lowest setting will induce some over steer in those applications.

For ANY car looking for the best 60', drop the LCA all the way DOWN! Most people see at least .10 off the 60' with the brackets at the lowest setting.

Steve

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Spohn Performance, Inc. - F-Body Suspension Specialists

 

Thanks Steve. I fabricated my own LCA brakets and the lowest hole is 3" down. My last race of the season is Sept 16/17. I'll re-adjust the pinion angle and move the control arms all the way down before I race again. I won't know how much of an improvement I'll get since I just changed from 3.27 to 4.10 gears and from 26" tires to 28" also.

Here's hoping for a 1.5 60' but I'd be happy with a very low 1.6