I have a 7MGTE in my 3000GT Turbo-A Supra with a huge, larger than standard turbo, and I want to up the boost.
What is the max boost I can safely run ?
I have heard that tensioning the head tighter than standard will help preserve the life of the head, and stop the dreaded 7MGTE blown headgasket problem. My supra has only done 65,000km, so hopefully the head gasket is still in good condition.
I heard tensioning it to 72 was ok, but should I buy new head bolts and torque it to 80 ? How much are new head bolts ?
Mine blew at 81,000 k's. You can tension the factory Toyota gasket with standard bolts down to 72ft/lb and not have any dramas as the factory settings are around 50 ft/lb - this is way too loose.
After blowing my head gasket i decided to go all out and buy a HKS 2mm metal gasket, and ARP studs (more efficient than bolts) these are able to be torqued anywhere up to 120ft/lb's i'm running mine at 80 and don't forsee any head gaskets blowing in the near future)
The ARP studs were $250 from Victorian Performance Warehouse and were shipped to me in about 2 days.
My advice is at the moment to torque the current settings down to 72 - this can run for years and years without any problems - even while running high boost. How much boost are you wanting to run? The standard CT26 is only good for a MAX of 14psi but can run pretty smoothly on 10-11, anything higher you need a new turbo.
How much boost are you wanting to run? Its really time consuming but you might wanna think of going for the MHG - i wouldn't want to strain the gasket too much without knowing what condition its in etc.
The only other problem i had with the ARP studs was that once they were in the head there was no room around them to get a socket on to do them up - i had to manually grind away the surrounds slightly in order to get em on there properly.
Thu, 27 February 2003 15:05
i'm running mine at 80 and don't forsee any head gaskets blowing in the near future)
