Hey guys, new to the performance side of the ls engines here. So ive got a couple questions that I hope can get me started in the right direction. The engine will be going in an 87 Chevy pickup 4x4. Used as my mud toy, will be mated to sm465 4 speed. Looking to put an engine together geared more towards torque (need to spin 40's).
Already have 2 donor engines which im hoping to mix and match together.
Engine#1) LM7 5.3 out of 2000 Silverado, complete engine, harness and ecm currently completely torn down. Had 200k

Engine#2) LQ4 6.0 out of 2000 3/4 ton, long block only, unknown condition and millage.

Hoping to use 6.0. Maybe swap on 5.3 heads? Hoping to not have to do any block machine work on either engine to keep costs down. Will 5.3 intake/injectors work with 6.0?

What should I look at for a cam? springs? rockers?

Thanks in advance for all your help.

 

bump for any info

 

If your looking for torque the 6.0 is the way to go .

 

+1 if you're going for torque then the 6.0 is the way to go.

Since you said you're on a budget I would go with one of the Bryan Tooley Truck Cams http://www.briantooleyracing.com/btr...-camshaft.html or the Cam Motion drop in cam shafts http://store.cammotion.com/mobile/60...-compression-2 since they're designed specifically for trucks and to be used with the cheaper LS6 springs and stock push rods. Another great option would be to talk to one of the sponsor's here about getting a custom spec'd cam shaft. They cost about the same but will be custom designed for your specific application. I personally went with Martin @ Tick Performance for a custom ground cam shaft.

You'll want to replace the valve springs and push rods at a minimum and it might be good idea to do a trunion upgrade on your stock rockers while you have them exposed. I wouldn't bother with an after market rocker at this point since the stock ones actually work really well unless you're doing a max effort build and since you said you're on a budget I'm guessing that's not the case.

A set of long tubes and a free flowing exhaust will also really help wake up that 6.0. Don't bother looking for high end name brand long tubes since the cheapy ebay headers will work almost as well and can be found for less than $300 shipped.

Since they're from the same year everything should swap right over from the 5.3 to the 6.0 engine. Depending on what cam shaft you choose and how you want the engine to perform you may want to upgrade the injectors to either some flex fuel injectors or 8.1 marine injectors that'll flow more and still be somewhat budget friendly.

Just be sure to tell your tuner everything you changed so they can match everything up in your tune and make sure you get the most out of your mods.

Post some pics of your project when you get a chance. I'm doing a 5.3/4l80e swap in my '89 K5 and love seeing other people doing square body LS swaps

 

Thanks for the reply, I will most likely go with the 6.0 unless I find something severly wrong on teardown. Since it was....FREE . Will most likely go with one of the cams you recommended as well as ls6 springs. Use stock lq4 pushrods? and what exactly is the trunion upgrade? Will also most likely port and polish the lq4 heads. Will be mated to hydro clutch sm465 with twinsticked np205. Not sure how to add pictures in the text so ill just attach them. Thanks for all the help

 

The LQ4 has dished pistons and the heads have large chambers. Anything you can do to raise compression will help a lot with the torque output

 

^^^ I agree!! A thinner gasket would help raise compression or a nice mill job.