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you can get custom made pistons to your compression ratio

or you can do it a bit cheaper and get NA F2 pistons in there. but remember that they have no Hyper something or rather (can never remember the term) crowns on them as turbo pistons. also remeber that with high compression you can not run as higher boost as on low compression.

if you are thinking of upping the boost on high comp, look into water injection
 

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Hypereutectic
basically high silicon levels in the cast aluminum(*corrected*) alloy. Increases strength, melting point. Get most of the advantages of a forged piston, with the cheaper price of a cast piston - material costs are more than a standard piston, but still cheaper than forged

Seriously, if you want to increase the compression ratio, you should just go ahead and get custom forged pistons. Hypereutectic are strong, but forged is stronger. And when you are dealing with a explosive situation like a piston... might as well get a better piston.

as for increasing torque. . .
A higher compression piston should increase torque, it will also increase the chance detonation under boost unless you add race gas, or more fuel, or as BlindFreddie suggesting, water/alcohol cooling to the intercooler.

But if you just want low end torque, why not just get a different turbo, and a custom chip? You can get a smaller turbo, so that it spools quicker, it would give you the boost quicker, which would give you more torque at a lower rpm, it's be easier to change the turbo than to replace the pistons. Of course you would loose top end performance, since it wouldn't boost as much at a higher rpm... just and idea.
 

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Or he could get a hybrid turbo with a similar-to-stock size turbine wheel but a larger compressor wheel. So it will still spool up quickly but will also generate more power. Something along the lines of the t-bird should suffice, with the stock MX6 turbine.
 

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moebius said:
Hypereutectic
basically high silicon levels in the cast steel alloy. Increases strength, melting point. Get most of the advantages of a forged piston,
Actually its a high Sillicone content Aluminum alloy
It has similarities with high Carbon content steel alloys
it handles high temps and pressures very well but the hardness of the alloy does also makes it brittle, making it maybe even more vulnerable for detonations than regular pistons.

look around in earlier treads, quite a few of them shows Hyperautectic pistons from FE DOCH and F2T with cracked ringlands.

i belive (but are not 100% shure) that with a more effective compressor and a better intercooler (lower intake temps,lesser thermal load on the pistons), the F2 pistons would do a good job in an F2T engine with stock boost.
 

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back to the point.....

yes raising the cr will increase the low end hp and torque, it will for the most part increase the hpand tq over the complete rpm range.

is increaseing from 7.8 to 8.2 cost effective? no, not when using just pistons. you can get that cheaper by milling the block and/or head.

you should be able to run as high as 9.5 - 10:1 for a cr. since these engines have aluminium heads, you can get it closer to 10, but i would say 9.5 to be safe.
 

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I can vouch for Fe3T's comment. I have nuked 3 hyperutectic pistons myself, on several different occasions as well as about 3 or 4 other members I can think of off the top of my head. hyper pistons suck. Ever cut one open? there's tiny impurities and air bubbles inside.
 

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If you're looking for more low speed torque and hoping not to sacrifice anything else (like top end or like reliability), you're dreaming. Nothing is for free.

If you want increased low speed torque, the best way is to get a short-duration, low-overlap, high-lift cam. What the cam grinders call a "trailer towing grind".

Cheaper than all that piston horsefluff, easier to install and it actually will provide more grunt.

It'll pull like a John Deere (and rev like one, too).
 
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