Alright guys, I picked up a disassembled LM4 engine for $350 yesterday. A good deal I think. Came out of a Chevy SSR, was taken down for a rebuild but never finished.
Anyways, it's a stock LM4 except it has 853 heads, which are LS1 heads correct?
Also, I'll be rebuilding this myself, so what recommendations do you guys have? I'm aiming for the 300-350 HP or higher range and I'm on a tight budget. To be honest, my budget for parts is about $200-300, so I'm gonna have to stick to bolt ons.


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In case anyone is wondering, I'm dropping it into a 1968 Ford Mustang. (I know, Ford and Chevy, WTF?) If it makes ya feel any better, I drive a Chevy Avalanche....
But I explored my options and a GM motor fit my budget and needs more than a Ford engine. For ford, I didn't want a 4.6 mod motor, and the 5.0 was too pricey. For GM the Ls1 was way too pricey and I didn't want an iron block, so the LM4 fit perfectly. Plus it was the only one I could find locally. The closest engine to it was a 160k mile LS1 motor for $1,200. Screw that!


Anyways, I appreciate any help and advice!

Thanks!

 

First, Welcome aboard.
Make sure you don't skimp on fastners.
Head Bolts, Rod bolts, Mains, and Crank bolt are a MUST REPLACE.
Should be a nice little motor.
FYI the LS1 is an aluminum block.

Very tight budget though - Don't think you'll be able to re-assemble it for that price properly. The gaskets alone will run you $200 for Fel-Pro's
Do you have Rings? Bearings?
To do it properly, you'll have about $1200 or more, but it will be new and you'll know what you have.

 

I saw this motor for sale, and considered buying it, so now, Ill watch this thread and kick myself in the ***...lol

 

sounds like you paid top dollar
coulda sold you my 6.0 for that price ...disassembled

 

Sorry for the late reply guys. I'm so used to getting forum notifications that I forgot to check back.

I knew the LS1 was an aluminum block, I was just saying I'm glad the LM4 is an aluminum block vs the LM7 iron block. Yes the rings and bearings are there, still in good condition.
Think I can keep it under $500? I'd really like to... I'm selling my 302 to hopefully make a little extra, if it sells that money will go to this engine.

Hehe yeah I guess I got lucky

It's pretty cheap I think, for GA at least. It was my alternative to the Ls1 and the only LS1s I could find had 150k+ miles and were over $1,000, way outta my price range.

Plus you're in LA, pretty far from GA, lol

 

Just an update, I sold my 302 so I've got a little cash to go towards this engine. Also, since this is going in a classic mustang, what wiring harness should I use? I know this is exactly what question you guys specialize in, but I'm just wondering what chevy harness and engine computer I should use? I realize I'll probably have to do a lot of modifying to the harness for lights and stuff like that.

So any recommendations?

 

200-300? You'd be better off just setting it aside and saving your money for a while. You're going to spend a LOT more than that just to put it together. Head gaskets and bolts will take a majority of that.

 

Ive had a good luck with the cheapo felpros from summit for less than 50 for a pair and stock headbolts for 60. 110 for hb and hgs for both sides isnt bad IMO. Main bolts can be reused as well as rod bolts. You will need new rings though, never bought rings for stock pistons so I dont know about prices on those. All other gaskets can be reused. Dont forget to hone the cylinders, a dingleberry will work but Id get a professional shop to do it as speed and grit are both very important to get the right RA for proper ring seal.

 

Thanks for the advice guys, I really appreciate it. I'm in over my head obviously, but that's not a first.

Also, what should I do about a wiring harness? I'm assuming a GM truck harness from '04 would be close to what I need, seeing as that's where it came from. What suggestions do you guys have?
I obviously can't afford something like a Painless Performance harness, I'd rather have an OEM harness and adapt it for the mustang. I'm assuming it'll be safe to use the same computer for that model of car.

For the record, this engine came in the SSR, Bravada, Trailblazer, and Envoy, so it seems I should look for wiring harnesses and computers from those cars. Please inform me of any other models I can look in, I'm assuming most of the later Gen-3 engined cars will be similar but I don't want to be buying the wrong parts!

Lastly, I want to apologize again for my lack of knowledge on the subject of the Gen-3 chevy engines, and engines in general. I got into the hobby with little knowledge but plenty of capacity to learn! I picked up the LS1/LS6 engine guide by Will Handzel and I must say it has TONS of info, but not these vital little details you guys know.


Thanks again guys!!!