Going to put in metal head gasket but...

drostar

New Member
Apr 24, 2005
60
0
0
SK
I want to change my stock head gasket to a metal head gasket before turning up the boost but I don't know what size of head gasket to get. When I bought my car used, I was told that the head had been rebuilt, so I would assume it was shaved down a bit. The problem is, I don't know how much was taken off. Is there any way to tell how much was taken off so I can get a head gasket size that makes stock compression? Or should I just do what I can keep the compression the way it is now (which I guess is higher than stock). What's the harm in getting a head gasket that is too thick or too thin?
 

Jaguar_5

It's ALIVE!
Feb 7, 2006
1,468
0
0
Seattle
My machinist had measurements for the block and the head to figure out how much had been shaven off of both, make sure you properly deck both surfaces for that MHG!!!

Using the wrong sized gasket, can mess with your compression ratio, too low and you'll have no power, too high and you'll detonate much easier, but thats a very basic explanation!
 

2543arvin

Moving to Japan!!!
Nov 30, 2006
879
0
0
Jacksonville, NC
I dont think that just because the head has been rebuilt necessarily means that they decked it, unless they put a MHG on it then......maybe someone else can chime in and correct me if Im wrong....
 

BorHor

2JZ-GZE
Jan 10, 2006
6,181
1
38
36
San Jose, CA
If it was rebuilt improperly then the head might not have been decked. But no matter what type of HG is used the head/block should be decked.