[SnowWhiteSS]

Alright, so I just did a few upgrades to my 17SS. Gpi SS2 cam, gm performance upgraded lifters, btr dual springs, hardened pushrods, c5r timing chain and arp head studs and rod end bolts. Already on E and have a ported Msd and 2” headers.

I’m worried about the valves though. I was watching a YouTube series where this kid did a ss3 cam and after a month of driving he broke 2 valves and ended up destroying both heads and a few pistons and sleeves. He was revving to 7300 rpm and said it was the pressure on the valve from the springs that caused them to shear at high rpm. I don’t know if it’s true or not but I DO NOT want this to happen to me.

Do you guys thing I’ll be good with the stock valves if I’m only revving to 7k? I’ve heard these cars have some issues with stock valve train but I thought it was from the springs not the valves. Should I have done valves too? I didn’t think about it while I was doing the heads to be honest. I sent them out to a machine shop and had everything cleaned and milled and totally forgot to get valves.

What are you guys thoughts?

[18.2SS.1LE]

I've been beating on mine for about a year at 7,100, no issues yet. Plenty of cammed cars running around without issues.

[adamjwilson]

Assume you got rid of the stock aluminum pistons and replaced with forged rods and pistons?

[KingLT1]

Some of the stock head failures are from aggressive cam lobes causing "valve bounce" and that tears up the valve seats. BTR revealed these issues even with their own products through spintron testing. Hence why they revamped their cam lineup to remedy the issue. GPI cams have a reputation for being hard on valvetrain parts from what I have seen. I wouldn't expect your valve train to live a long life at 7k with those parts imo. I would put a set of fully worked heads on it.

[18.2SS.1LE]

Originally Posted by adamjwilson

Assume you got rid of the stock aluminum pistons and replaced with forged rods and pistons?

If your question was directed toward me, stock pistons and rods.

[SnowWhiteSS]

So in other words, your saying I have theoretically built myself a ticking time bomb??

[Katech_Mike]

Originally Posted by KingLT1

Some of the stock head failures are from aggressive cam lobes causing "valve bounce" and that tears up the valve seats.

I agree with this statement.

We use stock valves in every build that doesn't opt for titanium and we have never dropped a seat or broken a valve.

We do Spintron all of our valvetrain sets ups to insure we have the best/most durable package possible.

[SnowWhiteSS]

Originally Posted by KingLT1

Some of the stock head failures are from aggressive cam lobes causing "valve bounce" and that tears up the valve seats. BTR revealed these issues even with their own products through spintron testing. Hence why they revamped their cam lineup to remedy the issue. GPI cams have a reputation for being hard on valvetrain parts from what I have seen. I wouldn't expect your valve train to live a long life at 7k with those parts imo. I would put a set of fully worked heads on it.

I’m not finding any evidence supporting that gpi cams have been known to be hard on valve train but I did research the Spintron and see that they do not Spintron test their equipment. Hindsight I should have gone with cam motion or Katech for peace of mind insurance but i don’t think it’ll cause too many issues If I don’t spin it to high rpm’s. I’ll probably set the limiter to 6900 and get heads when I do a rotating assembly later and boost.

[adamjwilson]

Originally Posted by 18.2SS.1LE

If your question was directed toward me, stock pistons and rods.

Actually, I was asking OP

[18.2SS.1LE]

Originally Posted by adamjwilson

Actually, I was asking OP

No need for forged pistons and rods on a H/C setup.

[SnowWhiteSS]

Originally Posted by adamjwilson

Actually, I was asking OP

Nope. stock rotating assembly. Should be fine

[SnowWhiteSS]

Originally Posted by 18.2SS.1LE

No need for forged pistons and rods on a H/C setup.

What lifters are you running?

[adamjwilson]

Originally Posted by SnowWhiteSS

Nope. stock rotating assembly. Should be fine

what are your dyno numbers? rwhp and torque?
As for lifters... I use only Johnsons- too any documented failures on LS7s but some have good luck with them.

[SnowWhiteSS]

Originally Posted by adamjwilson

what are your dyno numbers? rwhp and torque?
As for lifters... I use only Johnsons- too any documented failures on LS7s but some have good luck with them.

Mine aren’t ls7 lifters lol. They’re gm performance racing lifters. Good for 8k rpm tried and true. I have no idea the power yet because I haven’t dynoed the car yet. I haven’t even started it lol. I still have to put the radiator and intake back on and start it. Hoping for mid 500’s with the cam.