Needing info for LS build

[loudandgreen]

Hey y'all, I'm collecting info that will lead me to the right parts for a LS build i will be starting hopefully this coming winter. Am i in the right place or is there another category or even a different forum I'm suppose to be on? I tried the forum that rhymes with "hell mess one" but apparently you get flamed for thinking outside the box on that forum so i shall not waste my time with those types of people.

Thanks In Advance!

[Blue Bowtie]

What is the goal of the build? Quarter-mile, short track, road racing, speedway, daily driver, rock crawling, mud pulling, backup generation, and just about every other application would have a different set of recommendations. We'd love to help you spend your money. Just tell us how.

[silicon212]

To add to what Blue Bowtie said, also the weight of the vehicle, gearing etc would help us make recommendations that are tailored specifically to your application, in order to extract the maximum amount of smiles-per-gallon that can be had.

[loudandgreen]

I've only done reseal and head gasket work so bare with me.

I'm looking to build an aluminum LS (not sure if i want used block or new $1200 block), to keep things light weight as possible.

I haven't found a donor body yet but I'm keeping it simple so a 700r4 or near that(4l60 i think) with 3.73 rear gear in something as light as a late 80's rx7 to at most a square body chevy s10. I was hoping to run carbs but i REALLY wanna run a pair of webers being that's what I've tinkered with in the passed.

I'm looking into maybe 500hp+ for something to have fun with or and something that has enough torque to haul parts or even a little trailer to haul lawn equipment.

ALSO if any of you could recommend great literature on LS engines, building, porting, carbs etc etc i would be greatful because i am trying to learn this stuff as well.

[Blue Bowtie]

Just my opinion, but no carburetor will produce as much power on a naturally aspirated LS engine as the factory injection system. It certainly will not be as stable and reliable.

FWIW, I used the factory SFI system with a .550/.560 lifts, 220°/230° duration, an LSA of 109°, and 10.8:1 static compression. It idles with an almost undetectable lope, almost as if it were misfiring just slightly while idling at 650 RPM in Drive.

Some misfire - It shifts out of first at just under 55 MPH at WOT and breaks the 10" tires loose to a solid bark in the shift. I can run 91 octane in it if I have to with no detonation, albeit at a reduced timing thanks to the PCM.

I could never do that with any kind of carburetor. I'd strongly advise researching the original EFI system with upgraded injectors and TB before deciding upon a carb setup.

[loudandgreen]

I figured a carb isn't that efficient and it will need tinkering when temp changes or when its looked at funny etc etc. It's just something that i was never that great at but loved tinkering with it and learning. I had a few older 4cyl import engines and some were efi. I swapped on webers and my fav being the weber 38/38 outlaw.....i loved those, efficiency went out window but the power gain i felt was nice. I was hoping to possibly recreate that with the LS...and i know its 4cyl vs 8cyl but i just like carb.

I do how ever want 2 different set ups...carbs for weekend fun time and maybe TBI for longer trips.

I just don't like the bird nest efi system the LS came with, not saying that it's not efficient or it's not the best way to go....it's just not for me.

As far as cam options I'm not sure what i want but i wouldn't care if it was choppy...i just don't want to get into the realm of stall converters unless i REALLY have to.

I'm actually thinking about in the next few weeks to look around in the junkyard and find the 243 or the 799 casting number heads and start toying with those by cleaning them up and smoothing out the ports and see what i can do short of a machine shop to get them to flow what i need. Maybe that will keep me busy enough to keep from buying carbs that i don't even know if they will work with the set up im aiming for or not......I've even thought about tinkering around with the early 90s TBI found on the sbc and bbc back then just as a work horse.

[silicon212]

There are aftermarket engine management systems that you can obtain for your LS. You can tailor the parameters to your engine. Also, I would strongly suggest running a 4L60E transmission rather than the 4L60/700R4 due to the fact the engine management system will control shift points for you - again, in order to maximize power potential at any point on the spectrum.

[loudandgreen]

I think i just need to wait till my buddy retires in a few months and have him help with the setup i want.

Thanks Anyway!