I've got a '92 GSR with about 150K miles on it. I was going to have a friend of mine rebuild the bottom end with all stock parts come tax return time...but he asked me if I wanted to put some higher compression pistons in. I've never really thaught about it until he braught it up.

This is a dialy driven street car, and mabye an autocross event here and there (mabye once every other month), just for fun not to be competitive. I want to stay NA. I've got I,H,E, right now. Might do some mild cams and gears down the road.

Factory reliability, idle, longevety(spelling), and being able to run on 91 pump gas, and pass emmisions are my main concerns. Damn, looking back at what I want is it possible to up my compression and still maintain all of these goals??

And also, what else do I have to worry about when uping the compression? Engine management, fuel enrichment, dyno time???

Thanks far any advice.

 

depends on what you are going to do with the car. if its a daily driver and once and a while you beat on it & your looking for some reliability. i say go for some itr pistons i think will give some thing in the 10.5cr field and balence the whole bottom end, some arp rod bolts and shot peened the rods. that will give you some peace of mind and throw some cams in there too. it all depends on what you do with the car and how well you maintain it. this is just my 2 cents

 

10.5.1 comp

 

That pretty much what i'm looking for. It's my daily driver with an every now an then aggressive drive or autocross event. I've already planned on doing the ARP rod bolts, but is it necessary to shot peen the rods and balance the bottom end? Are those things expensive to do? Would I need some kind of tuning for that kind of comp increase?

Also, should I also go with the .25 overbore? I figured it would probibly be necessary on a car with my milage.