How much boost have you ran through stock Hbolts over torqued?

T

TRUBBS

Can You Keep Up?
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Feb 15, 2009
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just kinda curious, whats the max boost you have pushed through your truck with stock headbolts over torqued? what did you have them torqued down to ect...
 
40lbs. Stock turbo stock torque specs and all I know that's a low boost number but thats all I've pushed
 
55lbs everyday 130lbs with new bolts retorqued 3 times within 2weeks when cold
 
.020 over headgasket with bolts torqued to 155 ft.lbs. and 60+ psi. havent blown it yet. been doin that for over 6 months.
 
17cumminsboy said:
.020 over headgasket with bolts torqued to 155 ft.lbs. and 60+ psi. havent blown it yet. been doin that for over 6 months.
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Similar.. .020 over gasket bolts TQ'd to 150ft/lbs held 50+ PSI for a while...eventually excessive coolant pressure did get the gasket... this is on my puller.
 
i was thinking of doing a .025 over headgasket and overtorqin the bolts and try my luck with the turbos so that i can get the prodject done and on the road. then when i get more money saved up get the head port/polished oringed and studded

what did you do to the injectors to make up for the headgasket?

17cumminsboy said:
.020 over headgasket with bolts torqued to 155 ft.lbs. and 60+ psi. havent blown it yet. been doin that for over 6 months.
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Last edited:
TRUBBS said:
i was thinking of doing a .025 over headgasket and overtorqin the bolts and try my luck with the turbos so that i can get the prodject done and on the road. then when i get more money saved up get the head port/polished oringed and studded

what did you do to the injectors to make up for the headgasket?
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I did nothing with them in my truck and it works fine. running .020 over marine gasket as well
 
145lb ft and 65+psi daily driven for around 6 months without problems...was on a 300k mile virgin motor to boot...
 
CTDYoungGun said:
145lb ft and 65+psi daily driven for around 6 months without problems...was on a 300k mile virgin motor to boot...
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Stock bolts that came in the truck? Or did you put in new ones and TQ to that? I need to run my bolts in my 99 down some before I ad anymore HP to it and it has 220K on it.
 
ran 85lbs of max boost on stock headbolts, no blown headgasket with 100's of passes. But I was also running a lean combo that did not have much BP. Head studs went on today though after PP and valve job were done.
 
Got Smoke? said:
Stock bolts that came in the truck? Or did you put in new ones and TQ to that? I need to run my bolts in my 99 down some before I ad anymore HP to it and it has 220K on it.
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Loosened, cleaned, and re-torqued the stock factory bolts one by one. About 1/3 of them obviously stretched up at the higher torque, so the ones that did got removed and replaced with another stock bolt from a used set I had at the shop...took a while, but well worth the savings in my opinion.

That was with the hx35/ twin primary hx35 triples I had...so I know that I had a ton of back-pressure being built...timing never went above 20* static though either.
 
My Junker 95' with 241K miles is still running stock overtorqued head bolts. I didn't even loosen them, lube them, or clean them..... Just put the torque wrench on each bolt and started at 100 ft lbs and worked my way up. A few started moving "too much" around 145 ft lbs so I stopped torquing those 3 or 4 bolts. All of the rest went to 150 ft lbs plus a little... probably 165 ft lbs.

25* timing, mid 500 HP average down the track, lots of passes at the track, soon to have a nice set of twins.

When this head lets go, I'm going to go back with an oringed head, and new stock bolts, probably go to 170 ft lbs.
 
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