Hi all I know most of the pros for getting hi comp tt pistons but what are some of the cons to expect? I'm looking at you black beast Thanks for any advice Joe
What fuel? What cams? What turbo's? What power goal? High compression is good if you know what you are doing, ping city if you don't.
What fuel? E85 What cams? R4+ What turbo's? GT28RS What power goal? 400+RWKW That should do it assuming you mean 9:1 as high comp?
9:1 static or dynamic compression? What effect will R4+ cams have on your desired compression ratio? What compression pistons will you use to get your dynamic comp ratio? What will be the final installed height? What will be the combustion chamber cc including head gaskets? What do you think you will gain from higher compression? Also higher compression isnot worth doing on pump 98. E85 or better so you can atleast see some benefits from it where you are gfoing to want to use it. I would be looking at much larger than 2860's if you are going to run high compression. And I would be looking to run atleast 9.8 static to make it worth doing.
Well that's some thorough questioning although I'm am a mechanic I am not an engine builder ( would like to be one) I belive that 9:1 is static ratio of the piston and as for the combustion chamber cc I don't have a clue, sorry. I thought a higher compression would reduce turbo lag. Joe
Compression will reduce lag, but depending on fuel used will also reduce the ammount of total ignition timing you can have which will effect your power. You need to work out how much power and when you would like to start making power and spec the engine from there. The complete engine combo depends on those 2 answers alone. R4+ cams with 9:1 static is low compression, pretty well near stock when you calculate dynamic. Blackbeast is correct in everything except the comp ratio. If you were to follow his specs for cams, turbo's and fuel I would run 9.4:1 pistons at zero deck height with standard cc combustion chambers. If you do not want to plan your trips around where you can buy E85, stick with 98ron fuel, nicely ported heads and R4 cams with 8.9:1 comp.
If i was you i wouldnt bother playing with high compression unless youve got a hard on for E85. If your talking about 400+rwkw, you will have lag regardless. the high compression will take the edge off but off boost performance will still be laggy off boost performance like most turbo v6's. Go with low comp, make tuning easy , safer for your motor and you will still do big horsepower.
metal head gaskets in the appropriate thickness. Engine builder will determine what sizes u need by cc'ing it
I'm gonna be the engine builder lol So STD comp pistons and STD head gasket it is I'll just put up with the lag Joe
Geez now I'm confused what's the difference between static and dynamic? And if I was to buy pistons what would I ask for if I wanted 9:1 comp?
the Dr can explain the first better http://www.z1motorsports.com/product_info.php?products_id=39 with Z1 you can choose custom on piston choice
Ok so as black beast said what would be the problem with going 9:1 static with the r4+ if the dynamic comp ratio is almost stock, because wouldn't r4+'s with stock comp pistons lower dynamic comp lower than stock?
its still worth having someone calculate the compression ratio for you properly. if you use a stock head gasket you wont be able to adjust your compression ratio unless you use custom pistons. you dont know if teh heads have beeen skimmed before, you will be skimming them and decking the block.
