I’m looking for some advice/tips on building a solid bottom end for an h22 turbo build. I’m not really sure what kind of HP I’m shooting for but I want the build to be somewhat reliable. My understanding is around 400hp is the max on an N/A build and to do that would not be cost effective. It would be expensive. If it’s gonna cost some cheddar I would just assume build something with some real power. I’d have to imagine that 400 HP is gonna haul *** in the accord I’m installing it in. Does that seem reasonable at any level and if so what suggestions do you have as to the block, pistons and rods, and compression. Also should I sleeve the cylinders. I’m aware of the FRM cylinders on the H22. My understanding is that only one aftermarket piston is available for the FRM cylinders and it’s not really seen a lot of action to get some data from.

 

I'm by no means an H-series guru, but I do know the H-series blocks come in open deck and closed deck - that likely will make a difference in the power level you can use on the stock block. Do you know which one you have?

 

Mahle Golds are a recipe for disaster. They do work with the FRM sleeves but the tolerances have to be PERFECT. Even then if you get the car slightly warmer than normal even ONCE, you can kiss the piston skirts and your engine goodbye. It's a tale as old as time. A very select few will get lucky with them, but so many others have lit their money on fire by trying to use them.

Do it right or do it twice. The right way to do it is to sleeve it and use a standard forged piston.

 

If you stay with the Mahle gold pistons in the FRM sleeves, they have been shown to hold up to 500+ whp for awhile... IF they are machined properly upon install.

Most people prefer to just sleeve a block and have the known reliability of a normal forged piston. There are many options on rods and pistons at the power level you are looking at, but I will always recommend to check out Kaizenspeed, as they are one of the few shops still actively working on advancing the H22 platform. Sleeving can be done by many shops, but some are obviously better than others, so having a location would be helpful there.

The deck style vs crank size is always a toss up, as a closed deck block is going to handle high boost better, but the larger 55 mm mains in the open deck blocks do appeal to some people more as well.

There is plenty of info through the years in the Prelude section as well.