47-55.1 Rebuild SBC or install LS- Henry 1949 3600

[Coach529]

At a decision point.

Current set up is a very mild 350/350 combo. Both motor and tranny leak horribly but are pretty low mileage and run good. This past summer I lost coolant and it got hot. Not sure how bad.....I never investigate it further. Embarrassing, but life gets busy sometimes.

OK option #1

Rebuild SBC and TH350.

Option #1.1

Pick up a 700R4 and replace the TH350

Option #2

Ditch the 350/350 and pick up a LS and Tranny.

Looks like I can pick up a 150K-175K 5.3 LS, 99-2005 for about $750 locally. No Harness......

[Daze57]

a few new gaskets vs a later model motor with no harness -----hmmmm what to do

[Coach529]

Originally Posted by Daze57

a few new gaskets vs a later model motor with no harness -----hmmmm what to do

Definately not wrong............

[jweb]

I replaced a worn out 350 with a LS1/4L60 a few years ago. If I had to do it again, I would have just bought a GM crate 350 long block (usually good deals on Black Friday).

1. It's much easier and less down time
2. You get a new 350 instead of a used LS motor
3. Less of the "While I'm at it". This one gets the most expensive.

That LS truck motor will need a different oil pan and probably Camaro or Corvette accessories to fit. Then you've got motor mounts, headers, exhaust, driveline and fuel system to figure out also.

Don't get me wrong, I'm really happy with my LS swap and it would be my first choice if I were building a truck that doesn't have an engine already in it. Since your truck is basically done, I would just replace the 350.

[slowcpe]

I've been battling that myself in my truck. I like the simplicity of the sbc, its a direct swap and for the money you are buying a brand new engine; not one with 100k+ miles.

Now I'm probably going LS in mine but that's mainly because I have the engine, oil pan, transmission and fuel tank already. The rest of the stuff to get it on the road will cost me about as much as a 350 crate longblock. Way more if I let the "while I'm at it" get carried away as jweb stated.

[youngrodder]

Rebuilding the SM but seem more expensive but by time you upgrade your fuel system for the LS plus the wiring harness, I'm not sure it would be a lot cheaper. For resale sake a nicely done LS swap would in most cases bring more $$ and interest from a wider margin than a carbureted SB. I have had fuel injected engines in my last two builds and have zero regrets. I would write down the pros vs cons and see where you end up at. Better dependability and gas mileage are definitely positives that a LS engine would provide...

Good luck with YOUR decision...

Marc

[Driver_WT]

I would get a rebuilt SBC long block all day long. I have spent way too much time and money on conversions and "while I am at it, might as well ..." for my vehicle projects. 700R4 is not a bad idea.

[Coach529]

Resale is nice to think about........but is not really a factor.

Obviously budget is always a concern. Not a huge pot of money Unfortunately.

If I rebuild the SBC, I will likely do it myself.

[joedoh]

Originally Posted by Coach529

Looks like I can pick up a 150K-175K 5.3 LS, 99-2005 for about $750 locally. No Harness......

also no trans, no exhaust manifolds, no accessories, no fuel system (I know you had an aftermarket TBI EFI at one point but that fuel system is not compatible).

you are a "get it done" guy, not just a big talker, so I know you could run through the LM (it is only an LS style engine) swap in no time. and you would probably be deliriously happy with the cold starts, cruising, and power, especially with a modern 4 spd auto behind it.

but your setup right now is a known entity, rebuilding or replacing the motor will put you exactly back where you were before teardown. if there werent any things you wanted to change, why change?

[Daze57]

i think youngrodder said it best - ''Good luck with YOUR decision..'' although all the above ideas and suggestions are are valid .
its all a matter of what you really want --- i have been running my 350 for a while now and i have no complaints . do i want an LS ? sure ---it would be v v nice but i have what i need and it works fine for me --- i guess it all depends on budget and what works best for you -----my 02cents worth

good luck sir ---please keep us posted

[jocww]

I have an LS1 in mine out of a 98... dont do a pre 2000 the wiring harness is different. pre 98 had different heads. I wish i knew that going in, I would have waited for a 2000 up motor. But either pre or post 2000 its nice so far just turning the key and going. No need for choke or for me to gas it .25 way to get it started on cold start up. It sounds nice, it shifts nice. Altho I did put a fresh rebuilt 4l60e as the one i got with the motor was trashed by the previous owner. This is my second toy with the ls engines my other is a 73 fj40 with a lq9. While more expensive than my old sbc gen 1s I dont think i will be going back to the old stuff unless budget dictates it.

[mongocanfly]

Well....I'm sold on the LS...and if you were pulling the old 6 and wanting a v8 then theres no way I'd go sb...but I wouldnt do a LS with what you posted...it would have to be a complete package....even though I'm LS all the way ,since you already had a sb ,that might be your best option..

[Dan in Pasadena]

Having gone through this and swapped out a tired but well running 283 for an LQ4 I can tell you for certain the "while-I'm-in-there's" will eat your budget alive.

I too am very happy with the driveabiiity and power of the LS but with 20-20 hindsight I'd have been happy with a 350 or a rebuild of the 283 (would have cost more).

[Coach529]

Originally Posted by Dan in Pasadena

Having gone through this and swapped out a tired but well running 283 for an LQ4 I can tell you for certain the "while-I'm-in-there's" will eat your budget alive.

I too am very happy with the driveabiiity and power of the LS but with 20-20 hindsight I'd have been happy with a 350 or a rebuild of the 283 (would have cost more).

Yea the "while-I'm-in-there's" scare me.

The rebuild of the 350 and 700R4 costs are known.

[burnin oil]

You said it ran good but leaks. Why not pull it down and install new gaskets and bearings and run it. Grand cost of 300 bucks including coolant. Heck throw a set of rings in if you like. Doing a rering was common back in the day.

[youngrodder]

Originally Posted by Coach529

Yea the "while-I'm-in-there's" scare me.

The rebuild of the 350 and 700R4 costs are known.

I recently had a 4L60E rebuilt which is basically the same as a 700R4 and I paid $800.00 W/out a new converter (which was a good deal). I think you could expect to pay between $1,000 - $1,200. I hope this helps.

Marc

[Coach529]

Originally Posted by youngrodder

I recently had a 4L60E rebuilt which is basically the same as a 700R4 and I paid $800.00 W/out a new converter (which was a good deal). I think you could expect to pay between $1,000 - $1,200. I hope this helps.

Marc

$800-1200 seems to be what I am finding locally for a rebuilt 4L60E or 700R4. I have found a couple cheaper......but not sure I trust them.

[Coach529]

No matter what I do the SB needs to come out. Going to start that process and see what I find.

Thanks guys!!

[Daze57]

best answer yet !

[mr48chev]

I'd do a compression and leakdown test before I pulled it. That way you know if there might be an issue beside leaks. It doesn't do much good to replace gaskets if it has enough blowby to push the oil out past the gaskets. On the other hand a tight engine with good compression and that passes a leakdown test with flying colors shouldn't need anything except a set of gaskets and seals and go again.

I'd agree that If I was doing a V8 swap from scratch while building a fresh truck that wasn't going for a full traditional build I'd go LS based Fi, OD trans and all.

[evilokc]

I have to agree with just about everyone here. the sbc is a proven package that you can make as much power as you want with ease. you already have the motor. check it out and do some minor clean up. get the 700r4. there is a reason one is a motor "swap" and the other is a " conversion".

[evilokc]

Originally Posted by mongocanfly

Well....I'm sold on the LS...and if you were pulling the old 6 and wanting a v8 then theres no way I'd go sb...but I wouldnt do a LS with what you posted...it would have to be a complete package....even though I'm LS all the way ,since you already had a sb ,that might be your best option..

I agree. if I were starting from scatch the LS is the obvious choice. but from where he`s at have to stick with the sbc

[1project2many]

Meh...

LS or SBC? It's like tossing dog turds back and forth over the fence.

Be different. Four cylinder LNF Ecotec. 260 hp, 260 ft/lbs, engine weight under 350 lbs, and enough technology to make your tires spin. RPM works perfectly with original gears, with a torque curve so flat it will feel like you never run out of acceleration. And if it's not enough for you, the LNF is capable of being built to 400hp.

[whitedog76]

Even if you bought some aftermarket heads and had the 350 freshened up, you're still probably money ahead of what it would take to get that LS to run. As far as going to a 700r4, the benefits are minimal over a good TH350.

What's the old saying, "A bird in the hand is better than 2 in the bush."

Of course it is up to you. If your the type that can` t leave well enough alone, by all means, go LS. If it's a reliable cruiser, then the 350 is good enough,

[Coach529]

Originally Posted by whitedog76

Even if you bought some aftermarket heads and had the 350 freshened up, you're still probably money ahead of what it would take to get that LS to run. As far as going to a 700r4, the benefits are minimal over a good TH350.

What's the old saying, "A bird in the hand is better than 2 in the bush."

Of course it is up to you. If your the type that can` t leave well enough alone, by all means, go LS. If it's a reliable cruiser, then the 350 is good enough,

I would really like to have that OD in the 700R4, but have been doing some "soul searching" on that as well.

Rebuilding my TH350 locally with a shift kit and warranty is $700ish. 700R4 is $1,000 plus having to find a core, buy a converter, shorten the driveshaft and balance.