WDRacing wrote:Most of the SR's people are getting that are actually JDM are 1991 to 1995. So the head casting should be of the same, shall we say, technology. I've done some reading on quench. It's important for a completely tuned and balanced engine. Not somthing most people on these forums should ne concerned about. If you want big boost you have to lower compression. If you don't have the money for pistons and rods then a head gasket will allow you to raise the boost a bit without the fear of destroying your engine at anything greater the 10 psi.
I personally would design my engine with quench in mind. But I'm building an engine to except over 30 psi at high rpms. So the little things would help me out more then the average Joe.
WD
Regardless of the motor, when you increase the chances of detonation, then anything to reduce the chances are important. Quench is one of these. Lowering compression is another one. Frankly, a good, one, but changing to a thicker headgasket is a poor way to do this in comparison to using lower compression pistons. Quench is important on any motor that is asked to perform under extreme conditions. It also has effects on emmissions, but that's outside this discussion. If I were you, I'd pay attention to anything that reduces the chances of detonation. 30 PSI is pretty extreme and there are much better ways to lower compression than thicker headgaskets.
BTW, 10 PSI is mild for most stock import motors as long as the tuning is good. Even with the KA's 9.5:1 Compression, 10 PSI is relatively safe as long as you can get enough fuel to the motor to keep up with the amount of air that the motor ingests. Getting up over 15 psi, I may consider lowering the compression, but I would not use a thicker headgasket, unless I was compensatiing for material lost is I had the block and head milled.