I currently have the setup below:
Doc Race turbo mani
Turbonetics T04E
Stock cylinder head mild port job
236/242 OEM cams
Eagle H Beams
Wiseco pistons (9:1)
ARP head studs
Felpro HG
ID1000 injectors
Z32 MAF
Nistune ECU
I have checked the block and head for warpage and get nothing. Well, a .001" feeler gauge will not fit under my straight edge. I take my car to the dyno and is laying down 431 HP and 442 TQ. Everything looks good on the dyno and it is a clean run. But I have been noticing that I am getting combustion pressure leakage into my cooling system (verified with a block test) This is the 3rd set of ARP studs and HG I have changed for this issue. I was wondering if I would have better luck with a Cosworth HG? I have tried Cometics before and blew it at 10 psi boost. But is the Cosworth really that much better??? Also I tried the search button but there is really nothing on surface prep for this gasket.
Thanks in advance,
Cory
Cosworth head gasket. Better?
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- nissanfanatic
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Re: Cosworth head gasket. Better?
What are you torquing the head studs to? I never torque past factory spec on the 10mm studs.
Seems extremely odd that you blew a Cometic at 10psi...(?) I never had a problem on Cometic+ARP up to 32psi on a T04R.
Seems extremely odd that you blew a Cometic at 10psi...(?) I never had a problem on Cometic+ARP up to 32psi on a T04R.
Re: Cosworth head gasket. Better?
I have had better result with Cosworth over Cometic but I also had advanced boost timing with Cometic that lifted the head and separated fire ring. What degree are you at with 10psi? 93 or E85?
12.96 @ 116.36 - 2.1 60ft - 11/2011
13.1 @ 114 - 2.3 60ft - 8/2012
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13.1 @ 114 - 2.3 60ft - 8/2012
KA24DE-T
Build thread/Blog
YouTube Channel
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Re: Cosworth head gasket. Better?
Torqued headstuds to instructed 70 ft/lbs with Snap On electronic torque wrench.nissanfanatic wrote:What are you torquing the head studs to? I never torque past factory spec on the 10mm studs.
Seems extremely odd that you blew a Cometic at 10psi...(?) I never had a problem on Cometic+ARP up to 32psi on a T04R.
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Re: Cosworth head gasket. Better?
15* ish on the last load cells on the max rpm (6800 rpm) and running 19% alchohol, 65% 92 pump, 16% toluene IDK gasohol blend that we are experimenting with. No knocking or detonation via plug chop. Also no damage to anything else verified with a bore scope. EGT stable around 1300 deg on the top end. Although the first time around I stretched the heads studs and had to replace everything. Could it be too aggressive of a timing on the bottom end? I do peak 442 ft lbs @ 4500 rpm.supakat wrote:I have had better result with Cosworth over Cometic but I also had advanced boost timing with Cometic that lifted the head and separated fire ring. What degree are you at with 10psi? 93 or E85?
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Re: Cosworth head gasket. Better?
I did too originally and they stretched. Now I only torque to 60lbs ft. YMMV.
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Re: Cosworth head gasket. Better?
Cool. Another Cory. LOL Hmm sounds like a good theory.nissanfanatic wrote:I did too originally and they stretched. Now I only torque to 60lbs ft. YMMV.
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Re: Cosworth head gasket. Better?
yeah i once torqued my arp 10mm to 73 ft-lbs but it wasn't started. hopefully i didnt wreck them. i see id probably only torque them to 60 ft-lbs for an n/a build and maybe 65 or so if i boosted. but i do plan on going bigger studs one day.
no one has mentioned ;
kedbmx's 12mm arp2000's held 10:1 compression , 42 lbs of boost, 8000+ rpm, and 225 horsepower per cylinder !
cosworth gasket correct me if i'm wrong
no one has mentioned ;
kedbmx's 12mm arp2000's held 10:1 compression , 42 lbs of boost, 8000+ rpm, and 225 horsepower per cylinder !
cosworth gasket correct me if i'm wrong
1991 sil-eighty se sold
1995 bmw 540i written off
1995 pathfinder se, sold
1995 Altima gxe, sold
1995 bmw 540i written off
1995 pathfinder se, sold
1995 Altima gxe, sold