2014 SIM 1SS/1LE Search & Build Thread

[cdb95z28]

It was a good season at the track. I learned to trust the ST43's and really pushed the braking deeper. And as my RE-71Rs wore down, I kept getting faster. I then threw on the Goodyear SuperCar 3R in 305 which is the same tire on the front of the Gen 6 ZL1 1LE. These tires have a ton of grip. I believe there is more room to reduce my lap times further.

My OE 1LE differential was showing continued signs of degradation. Even after changing to fresh fluid it would spin just the inside, less loaded tire. This is common on 1LE's that see alot of track time. I also think the car could use a bump in power to help accelerating out of a few corners.

To remedy both, I purchased an Eaton TrueTrac and a set of AFE/Pfadt 1 7/8" headers/cats. I bought the TrueTrac from RDPstore.com. Steve had a Black Friday sale going on, and his price was fantastic. And he had it to my house in less than 48 hours, for which one day was Thanksgiving. He does not carry the AFE/Pfadt headers so I found a PA shop near Philadelphia that also had a Black Friday sale, and their price for the headers was unbeatable. CSPracing.com specializes in late model GM.

With the TrueTrac, I may be able to downshift to 2nd gear on a couple of corners and still be able to put the power down.

I do not think I am going to make any other changes except adding solid cradle bushings. I am currently running the Prothane inserts and while I did notice better cradle stability, I believe the solid bushings are superior.

I am also going to try swapping out the Z antiroll bars for the bigger 1LE antiroll bars. I think the car may have a tiny bit more roll with the 3R's, plus reduced roll will help with camber control. In the back of my mind is adding Detroit Speed's package, Speed Kit 1, which is their drop springs and front and rear antiroll bars.

[AG1LE]

Have you used CSP racing for any installs/tune? I'm not too far from them.

[cdb95z28]

Originally Posted by AG1LE

Have you used CSP racing for any installs/tune? I'm not too far from them.

No. I first heard of them when they introduced themselves with their black friday sales. I checked out their site and they just happened to have the AFE/Pfadt headers. Even with the PA sales tax their price was better than the next best. I dug around to see if they have some history. Looks like they've been around for a while, they have a youtube channel since 2007 with lots of videos and info. They are in a big market, they must be doing something right. Fast shipping, great communications.

[cdb95z28]

I've been buying from Steve at RDP Store also. Steve has outstanding communications, fast shipping and great prices. Great website too. I'm amazed that some vendor's online stores are a pain to navigate.

[AG1LE]

Originally Posted by cdb95z28

I've been buying from Steve at RDP Store also. Steve has outstanding communications, fast shipping and great prices. Great website too. I'm amazed that some vendor's online stores are a pain to navigate.

I've done a bit of business with Steve too (parts / tune) - great guy, usually has the best prices, excellent communication.

I recently moved to the northeast (I'm about 1.5 hr north of Philly, 15 min from the PA border) - need a good performance shop that isn't too far away.

[cdb95z28]

Originally Posted by AG1LE

I've done a bit of business with Steve too (parts / tune) - great guy, usually has the best prices, excellent communication.

I recently moved to the northeast (I'm about 1.5 hr north of Philly, 15 min from the PA border) - need a good performance shop that isn't too far away.

Cool, maybe CSP can help ya. Is your car almost complete, Jason?

[AG1LE]

Originally Posted by cdb95z28

Cool, maybe CSP can help ya. Is your car almost complete, Jason?

Good question...I’m honestly not sure what “complete” looks like...

[cdb95z28]

AFE Pfadt headers and TrueTrac diff install complete. I also had them Jet Hot coated. Car sounds good with the OE NPP. At idle, just a touch louder with the NPP flap closed, alot more louder with the flap open. I haven't taken it for a ride as the roads are full of rocks from winter and I need to get it tuned. The AFE Pfadts went in super easy. I had to unbolt the lower connection of the steering shaft, unbolted the motor mounts to raise the engine about a 1/2". Easiest header install I ever did. I was able to even torque all the header bolts and new spark plugs. I also had to spread the left and right bank tubes of the NPP where it connected to the AFE Pfadt cats. It was off only a 1/2", but a porta power had no problem spreading them. I also installed the Z/28 rear diff cooler. Brake calipers looked good from last years season even though I am braking later, but braking in a shorter distance. No burnt piston dust seals. I also installed the OE 1LE front and rear anti-roll bars (ARB's) which are 2mm bigger each than the OE Z/28 ARB's.

Other than a tune and a fresh brake/clutch bleed, the car is ready for 2019. I may install solid cradle bushings this year and experiment with adjustable tie rods for bump steer control. When I increased the caster well above the OE specs, the bumpsteer was unbearable. Track use tire wear was improved with the higher caster. If I can minimize the bumpsteer with the high caster, that would be a good thing.




Attachment 978019

[h018871]

How much caster are you running?

[cdb95z28]

Originally Posted by h018871

How much caster are you running?

Currently, 6.4*

IIRC, you did the Gen 6 radius rod install on your Gen 5?

[cdb95z28]

Geoff, I do see that you did the Gen 6 radius rods. Great work on installing them. I have been considering doing this also. My only concern is whether these aluminum radius rods are as strong as the cast iron of the Gen 5. In my case a heavier car with 100 TW tires on the track.

[h018871]

Weight difference is a few hundred pounds, spread that over four tires and it is minimal....in my opinion. Aluminum is quite tough these days, think about wheels.
I wanted to be a metallurgist eons ago, but ended up on a different path, so my opinion does not carry much weight (pun intended).
I suspect when in failure mode it would fracture rather than bend. As the arm is mostly in a tension load, even in a crash. IMHO not a big concern.
Definitely a personal decision though

[cdb95z28]

Originally Posted by h018871

Weight difference is a few hundred pounds, spread that over four tires and it is minimal....in my opinion. Aluminum is quite tough these days, think about wheels.
I wanted to be a metallurgist eons ago, but ended up on a different path, so my opinion does not carry much weight (pun intended).
I suspect when in failure mode it would fracture rather than bend. As the arm is mostly in a tension load, even in a crash. IMHO not a big concern.
Definitely a personal decision though

Good info, though the fracture vs bend depends on the grade of aluminum, just as for varying qualities of wheels. I would think an arm that will bend (to a point) is more desirable than one that would easily break. A bent arm is safer than one that will catastrophically break.

[h018871]

100% concur, bend is better than break I have a fairly high level of trust in the gm engineers, they’re going to put in a bit of over design in the suspension bits. Personally I’m comfortable