Valve train woes LS3

[Cruz-lo]

Today. 8K miles on new motor. Aftermarket heads with .675 springs .620 ish lift cam. Stock rockers with comp trunion upgrade. Started hearing ticking and found metal flakes in on the heads under the valve covers.
Here is what greeted me when I took the trunion kit out of the first rockers!

Before all this… 24K miles with stock heads same .675 dual springs with a .640 ish lift cam. Factory rocker trunions . 13 of the 16 lobes wiped out on the cam and one flat spotted lifter. With the exception of ONE intake rocker (which was replaced and prompted the trunion upgrade to all on this new motor) all the factory rocker trunions were perfect after all those miles!


Symptoms of a greater issue I expect……..

[BlackM6RS/SS]

What oil are you using?

[Cruz-lo]

VR1 10W30 now.

Was M1 5W30 with first set up.

[axis]

What's the part number on those PAC springs? I see .650, .700, and .750 springs. I don't see .675.

[Cruz-lo]

Originally Posted by axis

What's the part number on those PAC springs? I see .650, .700, and .750 springs. I don't see .675.

Sorry About that.. They are the .675 springs. Going to take the rest of the rockers apart over the weekend I hope. I will post up what I find.

[376LS3]

Those must be the 1208s. Way too much spring for that cam. Theres a lot of talk going on about those exact springs the last couple months. I am running the same springs as you. I am planning on changing cams real soon and will also be changing the springs out.

[realcanuk]

There is no reason to run more spring than needed for the cam specs. As said this topic has been discussed quite a bit lately but for some reason some are still recommending those PAC 1208x springs. I would say this is proof that they are too much.

[axis]

Originally Posted by Cruz-lo

Sorry About that.. They are the PCA .750 springs. Going to take the rest of the rockers apart over the weekend I hope. I will post up what I find.

Those would be the PAC 1208x's as mentioned already. Seeing that they are the common part between the two incidences, they could very well be the issue. I'll agree with the others in saying that those springs are too much for your cam. It's not that the PAC springs are bad, it's that they are too much spring for the application. Give Brian Tooley a call to see what he has to say. He is VERY helpful and will be more than willing to talk to you about what might be the problem. His springs are among the best you can buy. Many LS shops use his springs exclusively. They are also nicely priced as well. His .660 platinum springs are $100 cheaper than the 1208x's.

Brian Tooley

[Rhino79]

For a cam up to 650ish you wont need more than 400 open. This is exactly why trunion upgrades and short travel lifters cant help you when you have WAY too much spring. Id look into the Brian Tooley or the Nextek springs for the setup you have.

[Ject]

Oh wow that's some crazy wear on parts!

I just finished a whole discussion and debate about .750 lift springs due to this exact concern. I swapped over to some BTR .660 springs due to the concern of too much spring pressure causing damage to the valve train.

Hope you get things all fixed up and someone jumps in to get you headed in the correct direction!

Keep us Updated!

[JustaCamaro]

I have the Jannetty rough idle blower cam kit, with .600 plus lift. I used the supplied springs which I am sure were also Comp products. I had to tear the engine down due to an unrelated failure, and found identical wear on some of my trunions. Three of my exhaust valve stems had severe wear on them also.

I was using 10W30 Mobil 1 prior to the tear down. I didn't find any other oil related failures to include lifters or cam. I had about 4000 miles on the setup.

I am now using Gibbs LS30, with about 2000 miles on the new engine (LSX 429).
I haven't taken anything apart for inspection yet.

Wonder what they look like?

[christianchevell]

I would recommend using a spring more in the .650 to .675 as that was what I was recommended with my .639/.623 lift cam from TSP, and also using Driven racing br30 break in oil and ls30 after break in.....You know that the lift we have with our cams is already very large compared to regular flat tappet engines of old...and the spring pressure is already excessive at .675 and I will have to tear into my engine to check mine at 25k on the cam and am hoping they still have enough pressure and are good form using the best oil I can find.......one for our engines ! Read the tech bulletins on drivens website is what I recommend, and if you get curious about other oils read a lot first online......... Heres some links and zddp is crucial in our engines also especially if cammed.....

http://www.drivenracingoil.com/news/...-break-in-too/

http://www.amsoil.com/lit/g3115.pdf

[h018871]

Sub'd
Want to watch this one

[Cruz-lo]

Originally Posted by Rhino79

For a cam up to 650ish you wont need more than 400 open. This is exactly why trunion upgrades and short travel lifters cant help you when you have WAY too much spring. Id look into the Brian Tooley or the Nextek springs for the setup you have.

I checked all of these springs with my proform bench tester and found
155 to 165 pounds @ 1.8 (my installed height is about 1.85)
370 to 390 pounds @ 1.125 (spring is about 1.2 at full lift)

Could be my tester is not correct though....