i think im going w/ 88 or 89 mm pistons on my h22, what will i have to do to the head and cc to accept the bigger bore? or can i leave it for now till i have the money to really bulid the head in the future?

 

The best thing to do would be to have the head mated to the block and then scribe the combustion chamber to the same size as the cylinder. At the same time you should have the head ported and polished.

 

Some of the big name headwork places have said that you should leave the combustion chamber diameter alone when you overbore. Matching it to the bore supposedly doensn't do anything for you worthwhile. That's what the guys at Portflow said.

 

funny, Tom at Portflow told me the opposite

 

heh, and took an extra $125 out of your pocket No offense intended, as I have a Portflow head in the garage with the CC opened up as well.

I'd really like to know the true answer to this.

 

actually, i didnt pay any extra

 

"search". I believe there was a 3-4 page topic about that subject. Good reading

 

but i dont HAVE to right? i plan on keeping the head stock till i have enough to fully redo it.

 

the exposed edges increase the chance of detonation.

 

Am I imagining things? I could have swore Portflow advised to leave them be...

Here are a few topics to read through.

https://honda-tech.com/zerothread?id=173812&page=1

https://honda-tech.com/zerothread?id=156070

 

True.

 

Don't need the head to match the bore.

IF the pistons are made for the stock head.

IB

 

When is that the case?? How would you know that if you bore out the block to lets say 83mm, how would you know the pistons were made for the stock head?