New Supra owner has HG question. - Toyota Nation Forum : Toyota Car and Truck Forums

rwilliamson · 07-27-2005, 08:30 AM

I keep reading about the HG problem with the MkIII. I have a 89 N/A. Do I need to worry about the HG? Did toyota ever address the issue and fix it?

Thanks in advance for any information.

Jeeves · 07-27-2005, 09:53 AM

They've redesigned the head gasket 2 times, IIRC. Even with the new one, ARP studs and head work, it looked like it would have popped if I had left it on my motor.

If they're bone stock then with the redesigned head gasket and new head bolts/studs. Things would be fine.

And yes, if you have a 7M feel free to worry about the HG. While NA's pop them less, it still happens.

jsbenami · 07-27-2005, 04:18 PM

Is there any chance they made the second revision by the end of the MKIII run? I ask this because I have a late model III, its a 1992, and I've long wondered if they addressed the issue to the point where it would have made any difference.

Jeeves · 07-28-2005, 10:02 AM

They changed the torque specs for the head gasket at some point, but there is not a Mk3 that is not affected by the HG issue.