another f*** up!!

Bill UK · 06-16-2007, 12:55 PM

I wouldn’t be too concerned about marks on the head you highlighted, they are due to the block and stock gasket having a waterway and no waterway in the head, in other words the mark is due to the head having no waterway. Some supra owners have drilled through the head in that location to try and increase the cooling efficacy, not sure of the results or why Toyota didn’t continue the waterway through to the head. The surface finish on the head is normally left to a competent machine shop, lots of info in these links. http://www.aa1car.com/library/ar996.htm

http://www.q-e-p.co.uk/cylinderheads.asp

Stock cylinder head measures 116mm ( 4.567 inch) thick.

06-16-2007, 12:55 PM	#22
Bill UK AEM EMS Join Date: Jul 2006 Location: UK Posts: 891	I wouldn’t be too concerned about marks on the head you highlighted, they are due to the block and stock gasket having a waterway and no waterway in the head, in other words the mark is due to the head having no waterway. Some supra owners have drilled through the head in that location to try and increase the cooling efficacy, not sure of the results or why Toyota didn’t continue the waterway through to the head. The surface finish on the head is normally left to a competent machine shop, lots of info in these links. http://www.aa1car.com/library/ar996.htm http://www.q-e-p.co.uk/cylinderheads.asp Stock cylinder head measures 116mm ( 4.567 inch) thick.