Engine and Transmission Tech

Hi All

Well nothing is simple any more. I find myself needing new head gaskets for my 3.5. And suddenly I am faced with overwhelming choices.
Man, all I want is a head gasket.
Do I go composite (what is composite) or embossed? (what is embossed)?

Apparently the composite is .040 and the embossed is .016.

Is the idea to go with the smaller gasket so the fuel is compressed more?

Bruce

I'm no expert on this subject, but I just spoke with Glen Towery on this very subject yesterday, and he said to go with the steel (embossed?) gaskets, for the very reason you suggested - increased compression. He said the horsepower difference is substantial.

Hmmm, with half a point of compression?

I gave D&D a call and ended up with the embossed one.

Hi Bruce, It really depends on the engine configuration. If you have a "P6" type (pre 77) then you will probably have a high compression 10.5:1 motor ... if it is after that it could be low comp (8.5:1) or standard comp (9.35:1) if it is a vitesse engine ... the bottom line is that a 9.35:1 SD1 late engine runs a swept volume of 441.51cc and the difference in gasket thickness (going from shim tin to composite) would reduce the compression to 8.5:1. I personally would not suggest goint that low unless you intend to run very poor fuel or a blower of some sort .. the RV8 just doesn't like running at compressions that low naturally aspirated .. they get very "soggy". If I were in your position I would check the cc's in the block and the head to make sure before fitting ... I hope I am not too late!!! :)

Shaun

Thanks Shaun

I have a 69 Rover 10.5:1 compression