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Discussion Starter · #1 ·
Ok I want to put higher compression pistons in my 1989 B2200 F2

It will have the holley 6200 carb, pace setter header, and 2" Exhaust with out a cat, it is bored to 86.51 or .020

I found this site http://www.afabot.com/montero/fsm/acl_pistonproducts_pp99.pdf on page 150 you can find info about the pistons for a Mazda 929 and the bongo.

They appear to be a flat top piston. Does anyone know about the comp ratio on these and if they will work in my F2 with the stock rods.

By the way the head has not been milled but the block was decked. I dont know how much, they just told me they would only take off enough to clean it up.

The block has never been rebuilt before. Take a look at that site and tell me if you think those pistons will work and if so what would the approx comp ratio be.

I would like to have 9.5 or 9.6:1
 

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I assume you are using the 8 valve head....

As I remember flat top pistons in the SOHC 8 valve engines can be found in the F8.

you can work backwards from there to find out the combustion chamber volume, which is about 47cc from my calculations (from an F8 with 8.6:1 comp)

Thats nearly all going to be in the head, thanks to the piston having a flat top.

If I installed those into a SOHC FE, using a 47cc combustion chamber volume would produce 11.5:1 or thereabouts. same calculation but with an F2, results in 12:6:1 comp. probably a bit too much. The SOHC 8 valve head is not as good a design as the 12v, it probably needs 98RON to run 10:1.

I probably would use the FE SOHC pistons, that have a milder dish than the F2 ones, which would give you 9.6:1 according to my calculations.
 

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Discussion Starter · #3 · (Edited)
9.6:1 Pistons for my F2

FE it will be then, does it mater what year model of FE that I get them for?

I wanted to stay under 10:1 so I dont worry about detonation.
I can get some fuel with ethanol in it, it has 101 Octane.
I dont how that compares to 98RON.

I am not familiar with the RON values, I live in the US.

Thanks for the input.
 

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Discussion Starter · #4 · (Edited)
I've been asking around a lot here lately about what pistons to use in my F2 so that I can achieve 9.6:1 compression. Some say this is a good idea, some say it is not a good idea.

I know in the small block Chevy it seemed that most people wanted bigger bore and higher compression. I want a street able truck but something that is strong at the same time.

Can I use the FE or F8 piston in my F2?

I don't want to go over 10:1 compression ratio.
 
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