Head Gasket Thickness And Fitments

[Richie-Van-GTi 70 2 Cars]

following on from my other thread I can now confirm the pistons are hitting the head so the gasket is too thin. Id rather avoid fitting 2 gaskets if possible. So what other head gaskets fit? At the moment its got a gti6 head gasket in which is too thin,if anyone knows the thickness of it then it would be a great help as I know I can get a 1.4mm gasket. Other option is a td gasket if it will fit as they come in 4 thicknesses.

Not sure how thick I need to go though as it starts hitting at stage 1 tighteneing (35nm) it still requires stage 2 at 70nm then 160 degrees.

[welshpug 1,636]

take the head off, secure the liners in place if its alloy block, then measure the piston protrusion at TDC, measure all 4 and use the greatest one obviously.

 

the only data I know is that a protrusion of 0.54 to 0.77mm required a gasket with 2 notches, and 0.77 to 0.82mm 3 notches (TD engines)

[Bally 4]

www.cometic.com stock gaskets of any thickness. Just ordered one this morning

 

www.cometic.com stock gaskets of any thickness. Just ordered one this morning

[Richie-Van-GTi 70 2 Cars]

all sorted, its protruding 0.8mm so Im adding a second head gasket for now which is 1.2mm.

[brianthemagical 1]

all sorted, its protruding 0.8mm so Im adding a second head gasket for now which is 1.2mm.

 

is that as in two head gasgets in the engine at the same time? i seem to remember reading that the is a bad idea. have you given any thought to compression ratios?

[Richie-Van-GTi 70 2 Cars]

yes using 2 head gaskets for now, target was a CR of 11.1 which I think I may still get as Ive still got the stroke I wanted and the extra gasket wont come into play as it sits below the piston height (within swept volume) and therefore shouldnt make any significant difference.

Ive just torqued the head down, put an extra 20 degrees on final turn to ensure both gaskets fully compress. The engine now turns over freely. Took some rough calculations with a DTI and I make it to have .6mm clearance between piston and head. this also increased the space between valve and head by the same amount so I should now have sufficient space to run the reccomended advance on the cam