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DEEDS
03-29-2009, 10:41 AM
i got a 440 big bore kit in it with stage 3 cam and i dont think the head or cylinder is warped but i keep blowing head gasket and did torque down the head bolts properly i installed new head gasket and after taking it for about 3 ride it blew again... any ideal what this can be ???
CJM
03-29-2009, 10:49 AM
Did you retorque the head after breaking it in a bit?
tri5ron
03-29-2009, 11:11 AM
if you still are useing the original head studs,... that is most probably your problem.
Chances are, you can eliminate the problem with a set of HD studs.
Many theads here discussing blown head gaskets, and HD studs.

what compression have you been running on this 440 kit ?
drew416ex
03-29-2009, 03:10 PM
Originally posted by tri5ron
if you still are useing the original head studs,... that is most probably your problem.
Chances are, you can eliminate the problem with a set of HD studs.
Many theads here discussing blown head gaskets, and HD studs.

what compression have you been running on this 440 kit ?

X2
monkeyballs
03-29-2009, 03:29 PM
There is a good chance one of the threads are stripped or the one of the bolts are stripped..
Ruby Soho
03-29-2009, 05:14 PM
stock studs can't handle it. i had the same motor

put in the gt thunder studs and be done with it
Sanddraging28
03-29-2009, 06:40 PM
its the studs for sure. i had helicoils put in along with the HD studs. i run over 13 to 1 compression. never had a problem
dariusld
03-29-2009, 06:57 PM
Originally posted by Sanddraging28
i had helicoils put in along with the HD studs.

I don't understand.


"These heavy duty studs cannot be used if the cylinder was drilled and tapped for Helicoils or drilled and tapped for any other oversize studs with a differant thread diameter and pitch."
F-16Guy
03-30-2009, 08:16 AM
The GT Thunder stud kit requires that the original stud holes have not been oversized in any way. Once you drill and tap for Heli-coils, the holes are oversized and the HD studs can't be used. Heli-coils are an option for the stock studs, but tapping the holes for the GT Thunder studs using a roll form tap as suggested gives more strength than cutting threads with an ordinary tap. You can do one of the options, but once you do one, you can't do the other.

edit-- Just to be clear, you CAN use helicoils with the HD stud kit, but most people say it's better to tap the original stud holes with a roll form tap so that the threads and surrounding metal are more dense.