408 Procharged 17psi
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From: tampa fl.
408 Procharged 17psi Currently building a new setup - 408 stage 3 heads, sdce spring tension setup - makes 17 psi - having problems with the heads lifting on the driver side. I had the same problem when I was making 10 psi with stock mlg's, so I switched to cometics and still the same problem. I have arp studs torqued down to 75 foot pounds.
I'm starting to get aggravated -- could someone with a similar setup tell me how to keep the heads down???
HELP!!!!
I'm starting to get aggravated -- could someone with a similar setup tell me how to keep the heads down???
HELP!!!!
Originally Posted by 01Bird_of_Prey
Currently building a new setup - 408 stage 3 heads, sdce spring tension setup - makes 17 psi - having problems with the heads lifting on the driver side. I had the same problem when I was making 10 psi with stock mlg's, so I switched to cometics and still the same problem. I have arp studs torqued down to 75 foot pounds.
I'm starting to get aggravated -- could someone with a similar setup tell me how to keep the heads down???
HELP!!!!
I'm starting to get aggravated -- could someone with a similar setup tell me how to keep the heads down???
HELP!!!!
Problem#2 is with blown applications the heads need to have a very thick deck, like the AFR's and some of the new castings coming out in a couple of weeks. Cometic can back me up on this.
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On The Tree
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From: tampa fl.
Originally Posted by 1bad2k2ta
Are the heads o-ringed?
no not o-ringed I have a 04 block that all the stud are the same size
and are pro series.the funny thing is it leaks in the same spot driver side back
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On The Tree
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From: tampa fl.
Originally Posted by Bryan Wilkinson
You have a two fold problem. Your studs are not seated properly in the block and over torquing will cause block distortion and the heads will never hold.
Problem#2 is with blown applications the heads need to have a very thick deck, like the AFR's and some of the new castings coming out in a couple of weeks. Cometic can back me up on this.
Problem#2 is with blown applications the heads need to have a very thick deck, like the AFR's and some of the new castings coming out in a couple of weeks. Cometic can back me up on this.
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On The Tree
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From: tampa fl.
Originally Posted by Slowhawk
Torque the heads to 85-90ft/lbs with the studs. I'm guessing the 17lbs will be from a F1 since a D1 wouldn't have a chance 
It's a D1sc @ 56000-rpm@6500
Originally Posted by 01Bird_of_Prey
It's a D1sc @ 56000-rpm@6500
Any pics ??
Kyle
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From: MI
I dont know how the fast guys are keeping them on. But you might want to PM one of them. Harlan is keeping his heads on at 25+ PSI. Steve Turley and Mike Brown are keeping the heads on their car as well, its a 6.0L block, but I believe they are still using ported aluminum 6.0L heads.
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From: Centrifugal City
Were the ARP studs new?
1st time they need to stretch, also Cometic gaskets suck.
Now that ARP studs are stretched, if you go back to GM MLS at 75 ft/lbs I think you'll be ok.
If that fails, I'd check the head and block surfaces.
1st time they need to stretch, also Cometic gaskets suck.
Now that ARP studs are stretched, if you go back to GM MLS at 75 ft/lbs I think you'll be ok.
If that fails, I'd check the head and block surfaces.
Last edited by MelloYellow; Feb 3, 2005 at 02:33 AM.
Even ARP will tell you that once you run the engine, go back and retorque the studs again because of heat and stretching. I havent seen a problem with running good amounts of boost. We are at 13-15 PSI on some cars and we use the GM MLS gaskets, no o-ring. Are you tuning the car yourself? Or do you have someone doing it for you? A problem that you could be having is the tuning. Improper tune will lift heads. Hope this helps.
Rick
Rick
detonation 
Especially since it's always number 7, 5 & 7 are the notorious ones for running lean first.
What fuel, compression, cam, A/F, advance?
standard ARP studs and GM gaskets will hold 17 psi without a problem.
Especially since it's always number 7, 5 & 7 are the notorious ones for running lean first.
What fuel, compression, cam, A/F, advance?
standard ARP studs and GM gaskets will hold 17 psi without a problem.
Originally Posted by 01Bird_of_Prey
This is a brand new cast iron block. I put the studs in the 1st time as ARP instructed - all the way down hand tight. The 2nd time I lock-tighted them in by hand.
Call Cometic, they will verify this for you
Call AFR they will also verify this for you
FYI
Last edited by Bryan Wilkinson; Feb 3, 2005 at 08:02 AM. Reason: update
