Ok, sorry for all the build questions guys, i am tyring to plan my whole build before i get started. I noticed you guys speak a bit about changing manifolds. On my 5.3 i believe it is a 4 barrel throttle body mounted on top, unlike the front mounted intake and throttle body on the LS1 correct? I havent pulled off my air box or really looked at my 5.3 much yet. Anyway, what manifold do you guys usually go to? and what performance gains are expected?

 

It's basically the same as the LS1, just a little taller. The throttle body is a single blade just like the LS1.

 

Just like JR says, its very similar to the LS1 intake with the exception of the way the runners are designed, the truck intake has to go down a "hallway" at the top of the manifold before turning 180* at the rear of the manifold and going into the individual runners. the car's runners are open right after the TB if I'm not mistaken.... the truck intake loses efficiency at about 58-5900 RPM so thats why people who want to spin their motors up to say 66-6700, want to go to the LS6 or similar intake. they flow far better in the upper RPM range.

 

This is true. But I have heard from many people that the LS1 or LS6 intake swap requires a change in accesory pieces so the pulleys line up.

 

Basically the truck intakes will perform better for low end torque (designed for towing and what a truck should be for ) whereas the car intakes are better for up top. If you change to a car intake, yes there are accessories that are involved but there are writeups everywhere on here about how to do it using truck accessories and modifying them. Those who switch to a car intake have said that they lose lowend torque but gained a bit up top. It all depends on your goals.

 

So, if you are going to go from 5.3 to 383 stroked would the car intake be good since i have a turbo and the turbo will kick in around 2,800rpm and up?? Is the aftermarket intake by Fast any good?

 

Im not sure if anybody with a truck has put one on but talk to mjhoward. he has a similar setup to what you are talking about!

 

The F.A.S.T. intake is a little pricey, but it is probably the best flowing LSx intake. A friend of mine has a built LS1 T/A with 150 wet shot that gained 40rwhp on motor just from the intake. But as always, it's not so much the part as it is the combonation that you have.

 

[QUOTE=Out1aw]The F.A.S.T. intake is a little pricey, but it is probably the best flowing LSx intake. A friend of mine has a built LS1 T/A with 150 wet shot that gained 40rwhp on motor just from the intake. But as always, it's not so much the part as it is the combonation that you have.[/QUOTE]

See thats what i am thinking, since i have more air from the turbo and now i am going to have a bigger motor w/a new cam that will want more air yet, why not upgrade the part the distributes all that air...

http://cgi.ebay.com/ebaymotors/FAST-...QQcmdZViewItem
Hmmm... looks like i could run a nice 90mm TB too...

 

[QUOTE=Lord Aries]If you have the funds, GO FOR IT. And please post some numbers with your setup! I know im curious to see this