Shaving the head down

[94_eclipse]

Hi guys, this summer im planing on building my engine up a few more horses. I found a thread on this and i read it, basicly it said that its ok but not the best choice. and i agree. But for me it would be the cheapest and the easiest way. I dont have the time to rip apart the block to put higher compression pistions in. I just wanted to see what you guys feel is a safe amount to take down on my head. I always was told 10 thousands was a safe amount.

 

[impactpc]

I recently shaved a head .015 and it ran until the pipe that goes into the waterpump blew causing the head gasket to go. We are currently going to have to go another .015 at least to clean it up so I will let you know how that turns out. Let me remind you this is a 1g n/t with stock cams, pistons, rods, etc.

 

[dsm-onster]

The 4g61 has a smaller combustion chamber (44cc vs 47cc). The 1.8 has smaller chambers and the larger 1g style ports. That's a much better option than shaving. It bolts on and the timing marks line up.

The benefits of the higher compression probably are debateable because the smaller chambers cause the valves to be more shrouded. But, you'll gain 0.7 CR. From a stock n/t 9.0 to 9.7 is a good increase.