They don't come with a cable driven throttle body, you'd have to pick up one of Nick William's or some other company's 90mm throttle body. The NNBS trucks use the cathedral port heads, so that will be fine. there are some fueling modifications you have to do though. Read through that thread neilowns posted... probably from using the search function.

 

You'll never hit 600hp with either stock manifold,its just to much power..

For 600hp your def gonna want the F.A.S.T. LsxRT manifold and there 102mm throttle body..You would be leaving alot on the table if you didnt

 

Stock48 made 1100 rwhp on the stock 2003 intake / throttle body. But with a turbo

I say go woth the TBSS setup and the 90mm. See what improvements that gives you.

 

SweetS10v8 has extensive dyno time with the FAST intake, and mentioned via PM that the 102mm TB was only good for 2.5hp over the 92mm TB on a 750 HP engine. And the 102 TB is harder to tune as well due to loss of resolution at low blade opening due to the sheer size of the opening. Conclusion: 92mm is probably the better choice for almost everyone.

 

you can definitely hit 600hp on a stock intake manifold lol

 

@Imthedevildog What else can you do 11 years later?

 

Better late than never.