First casualty of fest??

[jjbrooks700]

Unloaded yesterday and started tearing her apart. Next time we are out it looks like she'll be stroked to 416.

[mp51998]

Wow. Makes mine look like a paint blemish.

[Ace0751]

WOW yup a stroker is in your foreseeable future, glad you didn't get hurt though.

[$inferno]

Originally Posted by jjbrooks700

Unloaded yesterday and started tearing her apart. Next time we are out it looks like she'll be stroked to 416.

Looks like my kinda luck. Good Luck with the build.

[Russell James]

Was the valve spring the cause?

You'll love the 416. I have a 416 stroker in my stock car that was at the NCM track thurs and fri. The stoker pulls great out of corners. Not a high revver, but the tq is great. Match it to a cam that builds tq early.

Some BTR or PAC springs maybe for the rebuild next time? I've got comp spings and lifters in now, and probably on borrowed time. I'll be switching to much better springs and some Johnson COPO lifters before the next track day.

[jjbrooks700]

I'm going to assume the valve spring was the cause. I have a pretty aggressive lsr cam and those were the comp valve springs.

[2SSRS@Gen5diy]

If you run the comp springs don't let them get more then 10K on them befor you replace them. IMO

[Russell James]

Originally Posted by 2SSRS@Gen5diy

If you run the comp springs don't let them get more then 10K on them befor you replace them. IMO

I agree. Seen too many fail to trust them anymore.

I'm switching to either BTR or PAC springs and Johnson COPO lifters. With a 416, a cam can be picked with a broad tq range. 2000 - 6600 ish. No reason to spin it real high when it makes so much power down low. It'll be easier on the valvetrain too not spinning it very high.

I've been having lifter and spring problems in my 416. Had Comp in both. Talked to a GMPP engineer this past winter at a trade show where they had some COPOs on display. I asked them which lifters they use in the COPO motors.... Johnson. He said call Johnson, and ask for the COPO lifters. The only ones that survived everything they could throw at the COPOs in testing. Valves springs, rockers, retainers.... the best the budget can afford. He said another key is to be careful with rocker tip weight. Too much tip weight can be quite a stability problem at high RPM. Beats the valves and springs to death. That's one reason the stock rockers with a trunion upgrade do so well... light tip weight.

[jjbrooks700]

Originally Posted by Russell James

I agree. Seen too many fail to trust them anymore.

I'm switching to either BTR or PAC springs and Johnson COPO lifters. With a 416, a cam can be picked with a broad tq range. 2000 - 6600 ish. No reason to spin it real high when it makes so much power down low. It'll be easier on the valvetrain too not spinning it very high.

I've been having lifter and spring problems in my 416. Had Comp in both. Talked to a GMPP engineer this past winter at a trade show where they had some COPOs on display. I asked them which lifters they use in the COPO motors.... Johnson. He said call Johnson, and ask for the COPO lifters. The only ones that survived everything they could throw at the COPOs in testing. Valves springs, rockers, retainers.... the best the budget can afford. He said another key is to be careful with rocker tip weight. Too much tip weight can be quite a stability problem at high RPM. Beats the valves and springs to death. That's one reason the stock rockers with a trunion upgrade do so well... light tip weight.

Thanks for all the advice. After talking to everyone at the fest and what I'm hearing here, my next build will be totally different! You live you learn.

[h018871]

sorry for your pain, as my wife said to me "this is an opportunity for an upgrade"

mine is a 418 with a BTR spec'd cam for HPDE & torque (while remaining a DD)
BTR 660 springs, trunion upgrade and new LS7 (stock) lifters. it pulls great out of the corners
engine dyno sheet

[fif_gen_powa]

Originally Posted by Russell James

I agree. Seen too many fail to trust them anymore.

I'm switching to either BTR or PAC springs and Johnson COPO lifters. With a 416, a cam can be picked with a broad tq range. 2000 - 6600 ish. No reason to spin it real high when it makes so much power down low. It'll be easier on the valvetrain too not spinning it very high.

I've been having lifter and spring problems in my 416. Had Comp in both. Talked to a GMPP engineer this past winter at a trade show where they had some COPOs on display. I asked them which lifters they use in the COPO motors.... Johnson. He said call Johnson, and ask for the COPO lifters. The only ones that survived everything they could throw at the COPOs in testing. Valves springs, rockers, retainers.... the best the budget can afford. He said another key is to be careful with rocker tip weight. Too much tip weight can be quite a stability problem at high RPM. Beats the valves and springs to death. That's one reason the stock rockers with a trunion upgrade do so well... light tip weight.

Good info here, thanks for sharing