i got an h23a1 and i know its a 2.3 but im getting the block rehoned so i can put cp pistons in there. and i would like to know the stock size and how much i should have shaved off the cylinder so the new pistons fit.

 

First of all you need to sleeve the block because only Mahle and JUN manufacture FRM compatible pistons.

 

i asked about sleeving. they said if i just rehoned and polished the cylinder i wouldnt have to resleeeve them. its to much money to resleeve

 

Then keep away from that shop, they dont kno wat they are doing. Your gonna need to sleeve to run anything other than the Mahles/JUNs/OEM. The FRM liners in the block wont allow for anything else.

 

He's right, stay away from that shop. The H series is nothing like the B or D series when it comes to the cylinder liners. Like said above the H series has FRM (Fiber Reinforced Metal) liners. These are extremely hard and have a different expansion rate as they heat up in comparison to those forged CP pistons you have. You even need a special type of hone to hone the FRM sleeves, which I'm thinking this joker doesn't have either...

 

Most reputable places will charge around 1k to sleeve the motor. in order to hone an H series motor you have to have special stones and it has to be done very slowly.

You can NOT run forged pistons in the H series blocks. forged pistons expand a lot more than the FRM sleeves. You will tear the hell out of you pistons and cylinder walls.

If you want to keep the stock sleeves look into Mahle Gold Series pistons. There are quite a few people running them and seem to be having good luck. Mahle claims that you can run them in the stock sleeves. I know CP used to make something that was comparable but I don't know if they still do.

if you want to run a forged piston you either need to sleeve the block, try the Mahle pistons or buy an f series.

 

are you all positive about this?

 

Mahle and JUN are forged, as well as the stock pistons in the F20c, F22c and C32a and those engines use FRM, it's just a matter of how they're forged and using the correct rings.

They are correct though about that shop, they probably have no experience with FRM and if you put those pistons in your motor it will tear it up.

 

if i go with mahle pistons will i still have to rehone the engine block?

 

and which mahle pistons should i get? and where can i order them?

 

Mahle Gold series, you can find them online. No, unlike normal cylinder walls you do not need to rehone the block unless there is deep vertical scratching. If there is, take it to a shop that can do the work properly. The instructions from the Helm's are posted in the faq's if you need to bring them into the shop.

 

You can get the Mahles here http://www.horsepowerfreaks.com/perf...Engine/Pistons

And stay away from that shop. It really sounds like they dont have experience with the H motors.

 

whats the helms?

 

Helm's manual; it's the factory Honda service manual. Order it here: www.helminc.com. This needs to be your next purchase if you want to work on your car.

 

i was just about to do the same as he was. saved me!

 

There are a lot of people that do not know anything about the material that is used for the cylinders. Most machine shops think that there is nothing special about them...that can really ruin your day.

 

i dont know what to do now. i wanna put new pistons but theres no way im resleeving the block. its way to money. is theyre anyway i can bore the cylinder and get a piston that wont screw my day up?

 

listen to what was posted above or go do what you want i ****-up your motor

 

Mahle gold series pistons are designed to go in the stock block without having to sleeve. that has been stated a few times.

no you cannot bore the stock sleeves to make a forged piston work.

 

mahle pistsons are forged though.
would they run without resleeving?

 

do some god damn research

 

It is the way they are forged and the coating they use. Yes they will work without sleeving. check out this thread


https://honda-tech.com/forums/showth...406865&page=29

 

/endthread

 

haha