Hi Everyone,
Sorry if this question has been asked , but I searched and did not find much.

My son and I have recently purchased a 2007 R56, awesome car by the way.
It was sold needing a head gasket, after disassembly and cleaning we dropped the head at a machine shop. When he was done he said he had to take off .016 to resurface the head, he also suggested we may need a shim to reassemble.

My question is how much is too much, he did not machine into the oil port with the ball in it. I see we can get gaskets that are up to 0.90mm/0.0354331in thick.

The gasket set we have is 1.2mm/0.0472441 thick.

Any information would be very helpful.

 

Not sure if this is obvious but I'll brainstorm. You can ask a speed shop to quote you a custom head gasket. Or you can use the 1.2mm head gasket and you know your compression is higher now. Or you can buy another head and source the one you have to someone.

 

Way back in the Stone Age we used to purposely increase compression in small engines. Would that slight milling be a negative? Could be it would work fine. Just a thought.

 

With these aluminum engines, percision is important.

Not sure what the implication is.

The question is did the shop take permission to perform the cutting? They should know better. If he cut it .011, then you can use the 1.2mm HG.

 

Here's an interesting article.
http://www.enginebuildermag.com/2007...-heads-blocks/
I suppose timing could be effected if milled too much.

 

The only two gaskets I've seen are the two mentioned --- 0.9 and 1.2 thickness. Either gasket should work fine. But to be sure, check the piston-to-valve clearance during the assembly process. Any increased compression will also result in a slight increase in performance and maybe a need for increased gas octane ratings.

Don't forget to use new head bolts. I also suggest the gasket set available from the dealer and probably other NAM sources --- much less costly than buying individual pieces. Then there's the Fuel Injector seals --- if you don't have the special tool, take the head, seals and injectors to a shop that has one. Virtually impossible to install these seals without the tool! Shop labor costs shouldn't be more than the cost of the tool.

As MiniToBe says, precision is important --- with a "shaved" head, the timing chain will have a bit more slack. The chain tensioner should take up any excess, but you should double check the tool measurement when setting the timing. This would also be a good time to replace the chain and guides --- another cost-effective set is available from a dealer or NAM sources.

Gets expensive quick doesn't it! Best of luck ---