The S1's would be a good choice. The S2's are designed for even bigger turbos than the 35R.

 

For some reason I was thinking it was the s1s up until the 30r or so and then s2s would be used after that.

 

Im pretty sure you are correct. S1 is good up to a 30r and like you said, s2 after that. Thats what GSCs website says. Lovin my S1s btw haha but I wont be going 35r.

 

The S2's would be a better option for a 35R this is pushed very hard on race gas, but for a stock block 500-550whp car, Greg is going to say the S1's are better. I don't want to answer for Greg, you can easily post your question in the GSC forum and he'd probably stand a better chance of seeing the thread and responding with his expert opinion.

He's wokring on a S1.5, or so he says in a thread in the GSC forum.

 

s2's would work great, s3's are the one that are rated for 40/42r turbo's.

 

It might be worth reading some of the threads in the GSC forum that Greg states his viewpoint. Here's a good one to start with regarding where the breakpoints for the S1 vs S2 are.

https://www.evolutionm.net/forums/sh...d.php?t=280996

And S3's are for those looking for 4 digit power.

https://www.evolutionm.net/forums/sh...d.php?t=296506

 

subscribed!
Im getting HTA 35R but i have a complete head job stock valvetrain with drop in pistons and rods!(wiseco+eagle see my sig.) Right now I have hks 280's i'm leaning on BR cams or Jun 272's im still doing research about GSC's.

 

on numerous websites it states the s2's r made for gt-35r and higher??

 

I already have HKS 280's and spin it daily to 8k without a single problem with the stock springs and retainers.

Monday I'm ordering the HTA 35R with tubular manifold and plan to run it as hard as it will go on pump gas before I start with meth.

I'll likely keep the HKS 280's in there at least until I do a built motor/head

 

really on stock block? no head studs or rod bolts upgrade?

 

I do have ARP head studs...forgot about that.

 

The BR cams are awesome but you'll need a good tune.

 

so many different options...way to make it a tough decision guys lol

 

hks 280's on stock valves/retainers??? and the stock valves/retainers r holding fine? wow

has anyone done a comparison between the two ?