I'm about to start building my turbo and want to know which engine i should go with. I have an 99 Si right now, so should I build a turbo for that car or get a Ls engine and turbo that?

 

Stock for stock the ls is a better engine to turbo, you can run more boost on the ls b/c of the compression ratio. You also get more torque out of the ls due to the displacement. I am running 15lbs on a stock internal ls and making over 300whp. Ls's are a dime a dozen and are half the price of a b16a block.

 

Turbo what you have, I think it`s the easiest route. If you are going to build the bottom end, might want to consider going b20

 

u can always buy a LS block and out your b16 head on it. then turbo that muthafucka!

 

i dont want to do ls/vtec. If i did go that route i would go all motor. the b20 sounds like a good good idea. thanks for all the reply

 

if u r building the motor, might as well get an LS and bore it out to the same as a B20 when u sleeve it.. just stick with what u have..

 

he already has a B16, why pull a good motor and put a less sofisticated one in. If you a doing a build-up compression ratios are irrelevant as you can chose when you buy your pistons. If you need extra torque just have it sleeved and bored to 84mm.

If you didnt have a good motor already i would say B20 or even a B17 for the shorter stroke depending on how you want to make power. But the B16 is a very good motor for boosting.

 

I just answered the question the way it was phrased. If the question said something about keeping his b16a or getting a LS to swap it I would have just suggested the b16a. Stock for stock though the LS is a better engine to turbo...there is no way that the stock b16a internals could see boost levels that would justify its perfect rod/piston ratio.