For the guys who have put a AU head gasket into their E series engine, has anyone had any piston to head clearance problems.

By my calculations if you have done this your piston to head clearance would be only around 25 to 30 thou with this gasket change. E series pistons stick out of the block just a few thou and the compressed AU head gasket is about 30 thou by my calcs (I may be a few thou out on this).

30thou is about the smallest recommendation for this clearance.

You would probably only know if the pistons were kissing the head on taking the head off.

Anyone know

I have to say that I doubt VERY much that there would be a problem with any gasket thickness on a stock cam. I'm turbo, 305deg cam with 550 thou lift and AU gasket. Although I did have 5cc machines from the chambers to reduce compression which puts the valve seat ever so slightly higher in relation to the piston.

Seriously though, Steve's turbo car which makes over 500rwhp is AU gasket, DEV5a (old style) cam and 9.5:1 compression. So lots of myths about turbo compression, cam etc all broken by us.

Thanks for that info. Whilst the info you gave me regarding piston to valve clearance is valuable and note taken I was actually chasing info on piston to deck clearance.

If anyone had a stock AU or BA engine with the head off it would be helpfull if deck to piston height could be measured and posted

And in that matter I can't help you, both of our cars have had chamber reshaping done and the valves unshrouded, so piston to head clearance is probably not really an issue for us. IIRC piston to deck height on both cars was not zero. If you asked the question about 6-8months ago I could have measured it for my engine. When we tear down Steve's to see what hes damaged I'll make a note to measure if possible.

i should have the head off my BA motor in a few days, ill check it then.

why would changing head gasket alter this?

Because the AU Shim gasket is much thinner.

Changing the head gasket wont affect piston to deck clearance but does affect piston to head clearance.

The guys who are putting AU head gaskets into stock E series mtrs are reducing this clearance to less than 30thou by my calculations which is generally accepted as a very narrow clearance to the point where the pistons may be kissing the head at high revs.

Reducing squish as its called is a good thing but not to the point where pistons touch heads. You would probably only find this out when you take the engine apart.

Nevertheless there seems to be alot of people who have done it but no real reported problems. If this is the case it might save me having to get 10thou shaved off the top of my pistons to get to a generally accepted piston to head clearance of around 35thou

This would be good. In the BA manual it states .3mm piston to deck, i.e the piston is .3 down from the deck but still interested if this matches up.