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Old 09-15-2012, 11:10 PM  
VIR Specialist

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Drives: Camaro Justice
Join Date: Jun 2007
Location: Virginia
Posts: 20,246
Lingenfelter L/28 Tech

Pedders R & D on the 5th Gen never ends. This week we ran at Road America with our friends from the OPTIMA Challenge. We got great data and great results. I want to than Mike Copeland, his wife and our driver Danny Popp for a great day! We spent the weekend testing with the Lingefelter L/28. The results were impressive and we got great data. The L/28 was brutally fast. We are going to make a few tweaks based on our data along with tire temps and input from our driver Danny Popp.

Videos from Three Optima Events


Speed Stop

Road Course

Data Points

Steady State Average Gs Across the Events and Lap Sectors 1.2 Gs. That is the AVERAGE. The theoretical limit on a street tire is 1.3Gs. we saw that number and then some across the events.
Top Speed on a Short Straight at Road America 148 MPH. That is screaming on the short straight.

Danny is extremely fast behind the wheel. His driving style is very aggressive. We found the front setup with -2.2 degrees of camber and caster adjustment maxed out to be virtually perfect. The tire temperatures inside to out were very even. The LPE motor puts down 590 at the rear wheels. Danny's style along with 590 all motor normally aspirated RWHP were roasting the inside of our rear tires. We'll dial down the rear camber to help Danny put down more power coming out of the turns. We have a few other tweaks in mind that we will share with the C5 community as soon as we test and get good data.

If the L/28 were a street car and not a street car wants to be a race car driven by a hot shoe we would leave the setup almost exactly as it is. Our intent is to still be a street car want to be a race car with even more bad attitude.

We are taking street car to a new level. To drive a 5th Gen fast you want stability and predictability in your handling. That starts at the foundational level with bushes. We want the arms to articulate freely, but within a tighter operational range. The amount of lateral movement in the 5th Gen lower rear arm with OE bushes and even with Pedders bushes is to great when you are looking for 1/10th or a 100th in a corner. We'll be testing this banded thrust bearing system this weekend. It is going to shift the load and our testing is designed to find out where ans what if anything we break on the Raymond's Performance Camaro and the L/28. Having survived the Danny Popp on track torture test we are pleased to announce the lower rear inner control arm banded thrust bearing solution is working well.

How stable is the Rear LCA Pedderised? This stable.

While we are on the subject of lower control arms, here is a how to on removal of the OEM lower inner control arm bush.

The OEM rear trailing arm bush is great for driving in the 8/10ths range. Pushed to 10/10ths or 11/10ths it allows too much movement creating instability. The increase in stability is enormous. Using a durometer you can see the differences in material hardness. Normally you wouldn't use a durometer to measure the hardness of steel. We did that for illustrative purposes. Both rubber and urethane soften with heat. The amount of heat generated by a 2 ton Camaro with LPE power through the exhaust and rear brakes is enormous. Using Pedders EP7265Z in the knuckle for the trailing arm reduces motion because there is less material and the material that is there is harder than the OE rubber bush.

Getting a good reading on the edge of the bush was problematic. The durometer is 85.

The L/28 running at the OPTIMA Face Off at Road America June 23, 2013.

Last edited by JusticePete; 06-26-2013 at 08:26 PM.
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