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deathangel · 04-20-2002, 08:14 PM

The real reason the head gasket blows is not what you said Nashman that is a myth because changing the bolt patern would have caused other problems

The reason they blow is because the bolts Toyota used were poor quality as well as the torque rating was wrong they were torque to 58ft/lbs and then 90 degrees the reason they did this was they were looking for stretch in the bolts what they didn't anticipate was the amount the bolts would stretch this coupled with the bad gasket, heat expansion, and vibration caused the bolts to back out and cause the gasket to oscilate on the block surface and causes the gasket to tear or when a cylinder is under high pressure the gasket blows wide open

So to fix this Toyota "re-designed" the gasket and "upped the torque setting" to 72 ft/lbs and this was done not looking for stretch in the bolts while they actually made better bolts this makes the "new" stock gasket good up to 17psi

changing the bolt patterns would have caused the head to crack because of the torqueing of the block it actually flexes under WOT because it is a straight six

don't believe me ask Reg Reimer!

04-20-2002, 08:14 PM	#165
deathangel Proud to be called a RS Regular! Join Date: Feb 2002 Location: victoria bc Posts: 148 Thanked 0 Times in 0 Posts Failed 0 Times in 0 Posts	The real reason the head gasket blows is not what you said Nashman that is a myth because changing the bolt patern would have caused other problems The reason they blow is because the bolts Toyota used were poor quality as well as the torque rating was wrong they were torque to 58ft/lbs and then 90 degrees the reason they did this was they were looking for stretch in the bolts what they didn't anticipate was the amount the bolts would stretch this coupled with the bad gasket, heat expansion, and vibration caused the bolts to back out and cause the gasket to oscilate on the block surface and causes the gasket to tear or when a cylinder is under high pressure the gasket blows wide open So to fix this Toyota "re-designed" the gasket and "upped the torque setting" to 72 ft/lbs and this was done not looking for stretch in the bolts while they actually made better bolts this makes the "new" stock gasket good up to 17psi changing the bolt patterns would have caused the head to crack because of the torqueing of the block it actually flexes under WOT because it is a straight six don't believe me ask Reg Reimer! __________________ "whats that whistling blur daddy?" According to einstien the faster you go the longer you live! Will race for food my toyota has a first name its: S-U-P-R-A Last edited by deathangel; 04-20-2002 at 08:17 PM.