High Compression Pistons

[twentyover]

I'm looking for high compression pistons for a 2.9. The most often heard production piston I've heard about is the Ford 2.8

Utilizing a nominal compression height of 1.527 " for a 2.9 piston w/ a 13cc dish and a 9:1 compression ratio, I looked at the 73-75 2.8 piston w/ a compression height of 1.511 inches, and found that yielded a nominal compression ratio of 10.6:1, while the 76-85 piston w/ a compression height of 1.535 yielkded a nominal compression ratio of 11.5:1. Both are a bit higher than what I'd like

Several times I've seen mention of a 9.8:1 piston. What application am I missing that gives this compression ratio? Compression height w/ no dish would be 1.482

 

[twentyover]

So I'm safe in assuming no onechere knows about a 9.8:1 piston I saw lised in someone's signature?

 

[AllanD]

If really want your truck to have more Balz the best way is to retrofit
a set of 4.0 pistons into it... along with the 4.0 crank.

but since the 4.0 crank won't fit in a 2,9 block you'd better use a 4.0 block as well...

and the 4.0 heads have bigger ports...

And the 4.0 uses a roller cam...

Just swap a 4.0 in the damned thing instead of pissing away several times as much trying to make a 2.9 "Better"

Ford already did improve on the 2.9, it's called a 4.0.


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[twentyover]

Agreed. The 4.0 provide greater displacement and some technological improvements.

But that doesn't answer the question I asked.