Oversized Type S pistons

jdmdanbb6bb4 · Post by **jdmdanbb6bb4** » Mon May 28, 2018 3:38 pm

Hi
I have been searching if there is any special tool to work with a FRM of the H22 Block to make the oversized bore, reason of asking these is because i want to put the Type S oversized piston on both of my Prelude the BB6 and BB4 but still havent found any straight answer on this topic. Can someone give some information about it.

what i know is:
Pistons:
A pistons have a size of 86.990 - 87.003mm
B pistons have a size of 86.890 - 86.993mm

Cylinder Bores:
A or I bores have size of 87.010 - 87.020mm
B or Ii bores have size of 87.000 - 87.010mm

And the Oversized Type S piston are .25mm

What i have check is what type of piston, have each block but still havent measure them.
the BB6 S spec has AAAA
the BB4 has ABBA

Cheers and thanks in advance for any information.

Post by **4thgenphil** » Mon May 28, 2018 7:45 pm

So what are you asking?

106pete · Post by **106pete** » Mon May 28, 2018 7:46 pm

Frm liners need a good machinest and a perticular type of hone to finish off. Your best bets are a porsche engine builder as frm liners aswell or speak to rich and sent it to his guy they have used for years.

I don’t think oversized type s spec pistons will be very cheap but nippon sell the same spec pretty cheap.

jdmdanbb6bb4 · Post by **jdmdanbb6bb4** » Mon May 28, 2018 8:26 pm

4thgenphil wrote:So what are you asking?

If there is any special stone or tool to work the FRM sleeves of the H22 block that will not destroy the FRM.
Because the Type S oversized pistons are 87.25mm and base of the information of the cylinder bore of a stock h22 block
Cylinder Bores:
A or I bores have size of 87.010 - 87.020mm
B or Ii bores have size of 87.000 - 87.010mm

If i want to install the Oversized Pistons it will need machine to bore the Cylinder so they will fit.

jdmdanbb6bb4 · Post by **jdmdanbb6bb4** » Mon May 28, 2018 8:31 pm

106pete wrote:Frm liners need a good machinest and a perticular type of hone to finish off. Your best bets are a porsche engine builder as frm liners aswell or speak to rich and sent it to his guy they have used for years.

I don’t think oversized type s spec pistons will be very cheap but nippon sell the same spec pretty cheap.

Thanks the only problem is that i dont live in the UK or US.
Well searching a lot came across with these ones that are not to expensive OEM Type S Oversized Pistons
https://www.icbmotorsport.com/jdmprbb6tysp2.html
and also have the OEM Type S Standar Piston
https://www.icbmotorsport.com/jdmprbb6tysp.html