A blind 20% bump in pressure is way too big to go and just recommend to everyone. The reason for the jump from 58 to 75 is that 58 is a commonly used torque value for cast iron heads. 75 is used in most things aluminum (your wheels, for example). People far more educated on matter than you and I came up with these values, their warranties are based on these values (yes, they will be able to tell). The head isn't as beefy as people like to think and the bolts and studs aren't immortal. Any, I'll reiterate that the value also depends on the lubricant used... if you're using 30 weight oil, your about right on... moly... well, whoops.

You can't really drill fasteners without compromising their elasticity. There's no way you're going to keep them cool enough for starters. And it has nothing to do with creating a vent, it's for measuring stretch and calculating the real clamping force. :bigthumb:

The dowels are not considered reusable actually... no reason they shouldn't be except that they're tapped into the block and getting them back out requires either pounding then in the rest of the way so they fall into the coolant passages or mauling the living hell out of them to pull them out the top. This came from a Toyota tech, there's nothing in the TSRM on the matter as they don't expect you to remove them at all.

Good point well made & no I wasn't really considering the use of moly lubes (which I now note you recommended earlier) as I'm a cheapskate (read blind-skint!) and my 90 on stock bolts was achieved using 2t oil IIRC. I wasn't really recommending anyone else go for 100 on ARP bolts mind, just observing that if I had fitted them I would have probably gone that far (but then I guess if I could afford ARP bolts I could afford decent assembly lube also so maybe not...) :dunno:

Again good point on drilling of fasteners, looks like someone's not really got their brain in gear yet today... Think a beer or three might get me cogs turning again... (Am I gonna end up famous for saying "it seemed a good idea at the time" some day?)

Anyway I got the hint that the dowels aren't really intended to be removed by the way said lump was mauled at the front of my motor, I'm still cursing the now defunct total-engine ltd! but it's still gotta be worth remembering that the holes in the head have to be clean too & checking the same bodgery hasn't happened as mine resulting in a burr that the head could sit on, and the 150/200mi retorque is essential IMO no matter what anyone says it's a hassle but what price being sure it's not settled?

wow so im pretty sure my mistake wasnt the threads but the moly lube. i used it the first time i re assembled the head but on the second and third and fourth and.....

so by the time i had the finished product i used 30 weight at 85 lb of torque.

when i was torquing the bolts they went in smooth with no slipping but should i still tap them? i know for sure im going to check my head for warpage and have it cleaned. bet its all nasty. should i do anything to the block?


thanks for this valuable info. i would of had no idea and probably would have repeated the process. kinda funny that i have had this supra for quite some time but have barely driven it but still manage to continue projects while starting new ones.....

im hopeless.