Hi guys! so i'm new to this site and i'm looking for a lot of suggestions on how to go about this build. I'm a newbie to the ls world, the most i've done is help my buddy rebuild an lq9 for his truck with a mild cam swap. So what i'm wanting to do is build an ls for my 98 Silverado, soon to be solid axle swapped, 37" tires and 4.56 gears. I was planning on getting an lq4 block to start with, putting in a callies 408 rotating kit, swapping the heads out for some chevy performance ls3 heads and perhaps an l92 intake. The part that i'm really not sure about is what cam to go with. I'm aiming for 500 bhp, but i'm also wanting a good amount of low end tq being that its going in a truck. Obviously anything is going to be a huge improvement over stock, but i see a lot of guys making most of their power well above 5000 rpm, which really isn't going to be usable for me. So how can i go about this and make big power in the low end? is it really going to be all in the cam, or am i going about this whole build all wrong?

 

You want 500 horse at the crank or at the tire ?
Is you on a budget as far as cylinder head goes ?

 

500 at the crank, I'm trying not to break the bank on heads, and the chevy performance ones are only $1300 a pair and fully CNC machined which is what made them really attractive, I'd spend a little more if it would help performance but I'm not looking to drop $2500 on them

 

You mentioned torque...... This is what I would do personally. You don't need a L92/LS3 head to make 500 horse. It's easily achieved with a pair of factory 317 heads which is what most 6.0 motors come out with. They can be picked up for a 100 dollar bill. Pick up a 317 head or a 243/799 casting head and send them to a vendor for a CNC port job. Texas speed offer a program starring at 750 bucks and up.
On the intake you'll have enough room to run a Trailblazer SS intake with a 92 mm throttle body. It's really a steal for the power that can be made with that intake.
Then as far as a cam selection goes I would call Martin Smallwood, Brian Tooley, Kip @ cam motion or Pat G.

Those 317 heads made 540 horse at the crank with a 239/255 cam which is badoff on specs..... With a well matched cam and a mild port job you be able to run a small torquier going and still clear your horsepower goal.
Main thing you need is headers, a Trailblazer SS intake, and a good camshaft spec to your heads.

Here is a great link. Read and learn and good look..

http://www.hotrod.com/how-to/engine/ccrp-1208-ls-cathedral-port-vs-square-port-heads/

 

I would suggest the cathedral heads as well. Stock 317 or 243/799 heads could hit 500hp at the crank easily with a good cam.

 

Thanks guys this has been a ton of help!

 

500hp is no problem at all. You can do cnc porting on your heads from TSP for a very very reasonable price!

I'd be happy to help you with a stroker rotating assembly to get you rocking and rolling! Just let us know when your ready! With several hundred crankshafts & rods in stock I bet we have whatever combo you want to build!!

 

so 408 out of an lq4 block, ported 317's, trailblazer intake, thinking cam similar to the one in the link above 23x/24x .624/.624 114 separation, and 36# injectors? sounds like a recipe for over 500 crank hp?

 

Unless you have a great relationship with a local machine shop or one of you works at a machine shop, I recommend buying a short block assembly. It will almost certainly end up being cheaper in the long run. For 500 crank horsepower, your heads just the way they are will be fine, but more power is there for the taking with better heads. Better heads will make more power throughout the power curve. As for your cam question, yes correct camshaft selection for your particular application will be very important to assure you get the powerband you need.

 

I wouldn't even port the heads. You can hit 500 on a 408 with stock 243s.

 

The advantage to buying a completed short-block from a trusted LS supplier is you know your getting a part that's proven. For example the TSP short-blocks are all cnc machined, cnc digitized, and cnc blueprinted. Infact we install both torque plates & motor mounts to simulate the block being assembled when it gets honed! Its attention to details like this that really help!

 

Just called your shop to ask a couple questions for my ls1. Lonnie answered the phone and helped me out a lot! i bought the v4 Cam from him. Very helpful guy and will be sending my computer in the next week or so!