So, it's a repeated topic, but the search came up with not so much helpful info, so please be nice.
I have a H22A1, and was thinking about type S pistons, but when i searched i cam across the floating rod thing...where the type s piston won't connect to the stock H22A1 rods, but will for the A4...How much/difficulty money, and where do you go to get the A1 rods modified to accept the type S? And do I need to check whether my stock pistons are A or B, does it matter if I'm swapping to type S?

Also, besides rings, what else do I need to know about this install? fuel increase etc, camshaft change? valve change? I'm a total newbie when it comes to pistons, thanks.

 

The incompatibility is from the H22A4 and also the Type-S pistons is in them having "floating wrist-pins". I honestly don't know how difficult or what exactly is involved in getting them to work with H22A1 rods, but I would like a clear answer on that just as you do...


[Modified by Mike95lude, 12:17 AM 3/2/2003]

 

I had my h22a1 rods bushed on the wrist pin end with bronze bushings at my local auto machine shop.So far 30k+ miles and still runnin strong.

 

How much did that cost you? And what's a "local machine shop"?

 

The place i went to charged me a a bill for the job,also since i had them polish my crank too also.Its just a automotive machine shop in the city where i live.They havnt done many import stuff,but they knew what they were doin.im sure most machine shops can do it for a reasonable price.

 

I recently installed a set of oversize type s pistons in a H22A1. I used a set of eagle rods because I needed new ones and they were the cheapest I could find. They make two kinds for the H22, .866 wrist pin and .865 I think. You want the smaller pin size. Just tell them you want to use the H22A4 pins and they should send you the right ones. If you want to re-use the old rods, you can have a shop check them out for you and install bushings like the other guys were saying. I dunno if this would weaken the rod significantly or not. I've not had the opportunity to compare H22A1 and A4 rods. I've heard the Type S rods are better, but again never seen a comparison. If you go this route, tell the shop you want 0.0005" clearance on the pin. I dunno what the A4 manual says, but this was the spec reccomended by eagle. Another possibility is to buy a used set of A4 rods from someone who is going turbo. I tried this at first but had several guys flake on me. It might work out for you. For piston sizes, check your helm and your block stamp. Or better yet take measurements after teardown. A is slightly larger than B, or you can get oversize pistons if you want (or need) to re-bore and hone the cylinders. If you get the oversize pistons, be sure to get the oversize ring sets too. Most of the A1's Ive worked on had B pistons, so if you have mild wear you might be able to put in A pistons with a light hone done to freshen up the cylinder walls. Anyway this was something I have done, so I thought I'd try to do my part to put some TECH back into honda-tech. I agree the search sucks. It would be nice to have the ability to search the contents of posts, and not just the titles. Ok, good luck and let us know how it goes...


Oh, I thought of one more thing. It seems like most people are slightly enlarging the valve releifs on the type S pistons, as well as sanding the domes some to reduce hot spots. Honda Tuning has had a few articles on this setup also. Check them out:

http://www.hondatuningmagazine.com/tech/0211hon_swap/
http://www.hondatuningmagazine.com/tech/0301ht_dprhead/

Other than this there are no other mods required to use these pistons that I know of. Higher octane fuel would be in order from the raised compression.






[Modified by flyrod, 2:00 AM 3/3/2003]

 

wow, for once an indepth answer, that answered all that I could ask, thanks flyrod

 

Why are they sanding down the piston tops for?im sure honda put the coating on top for a reason.The h22a4 rods are much thinner in many areas.They were probably made to handle the stock power and thats it.And yes,the type s rods or eagle rods are another good alternative.

 

There is no honda coating, just the cast surface. Sanding smooths out this surface so carbon doesn't stick as much, and less chance of hot spots. There are also raised letters for the engine code, and a little arrow. Those get sanded smooth.