ideal turbo piping diameter

[kristofer_turner]

hello all.
Well i am doing the good ol reserch before i start purchasing the rest of my turbo parts, basically all of it.
 I do however have a manifold sourced from ebay, this was only priced at 270 euro of the german ebay. (less wastegate attachment) but are these manifolds any good? (heard here they are prone to crack at the welds) im aiming for 250 hp at the engine. A T3/T4 turbo with an integral wastegate will be order soon. Im looking to have a smooth engine,with minimal LAG.

 But the main reason i have put up this tread is to find out what is the Ideal piping diameter for certain power outputs??  I have a 2.5" in mind, the same as my freeflow exhaust and both inlets and outlets of the turbocharger. Any help much appreciated,
thanks in advance

rocking forum

[+mtxmatrixx]

2.5 all the way......

[rob_e30]

Bigger is better and backpressure is the enemy of making turbo power.  We run 3" all the way, but might not be practical for everyone.

[kristofer_turner]

2.5 all the way......

ok thats great. then im on the right track.. or am i ??....  I have a slight problem. i have the steering on the right side, its a uk car and the steering col assembley runs right past the header and there is that small gap aswell to think about. do do you think the turbo will clear that far down or will it rise above that and out abit further?? thanks

[kristofer_turner]

Bigger is better and backpressure is the enemy of making turbo power.  We run 3" all the way, but might not be practical for everyone.

i hope you dont mind me asking (i bet you get it all the time) but how much power does your car make at an average dyno run ? cheers for the info

[rob_e30]

i hope you dont mind me asking (i bet you get it all the time) but how much power does your car make at an average dyno run ? cheers for the info

About 280 HP and Ft-lbs of torque at the rear wheels on a Dyno Dynamics.