We did some testing on a 2007 Silverado 5.3L engine. It’s a new body style truck that comes OEM with the 90mm throttle body and what looks exactly like a TBSS intake manifold which we were swapping to a FAST LSXRT truck intake manifold.

The truck tested was 100% stock, and there was no tuning done during testing, the OEM 90mm DBW throttle body was used on the 102mm intake.

The intakes were fairly close below 4500RPM, but after 4500 RPM is where the FAST LSXRT started to take off!!

Here are the power gains.

4500 +3.5rwhp
5000 +17.3rwhp
5500 +20.5rwhp
6000 +19.8rwhp

 

thats impressive with stock tuning!

 

you should tune it and see how much a difference a tune and a manifold makes

 

thats pretty impressive

 

Nice gains !! But whats that setup cost ?

Looks good for sure.

Def would like to see a tune and CAI.

 

Very impressive, especially since it hasn't been tuned

 

I didn't know a stock tune went all the way to 6000rpm, mine was limited to 5500rpm or so, but it's the previous model truck (2006).

Nice gains, it can only improve with a tune. How's the power under the curve by the way?

 

You can see how long it takes the stock tune to richen up... then it over richens to like 10.2...

Nice gains. These would be multiplied if you had cam, free exhaust, tune, and the 102 TB.
So i might look into this.

 

ive wondered myself what the gains were on a 5.3. nice gain for sure, would also like to see update after tuning.

 

wow, thats impressive, but $1000 for 20 topend hp is steep. i would like to see what it does tuned too.