Engine questions. Opinions are wanted.

[Mains52]

Ok dudes,
I have an 02' 5.3 right now I bought it for 400 w/ 170k on it. I started the stand alone harness my self and pretty much have what needs to be out..out of the harness. I am currently trying to trade my 4l80e for something that bolts up to the 5.3 without different this or that. Heres where I want some opinions for my questions.
1. I'm only wanting 350-400hp would it be dumb to just get rid of the 5.3 and grab an old school sbc or bbc?
2. If I keep the 5.3 would having a Muncie M22 be a decent trans behind it?
(A guy wants to trade an m22 for the 4l80e)
3. Do I just keep the 5.3 carb it for the ease of it and run the son of a gun?

Thanks in advance.......I think!

[Jemezcrusher]

a 350-400 HP SBC is not cheap

I would stick with the LS if you already have it

[Killer Bee]

lots and lots of options and lots and lots to discuss..

bottom line though, you will have to make some decisions and develop your plans from there..

here's another forum to do a little research, LS1TECH

400+hp out of a 5.3 is it possible???

good luck!

[e015475]

The NV transmission that came on these trucks is the only plug and play transmission unless you're willing to step up to a T56 from the LS powered Camaro/Firebird/GTO. Even if you go T56 you'll need to do something to get the shifter in the right location for the truck.

To get the M22 to work, you'll need a flywheel (aftermarket Sachs or a GM), the LS3 pilot bearing, a big-block clutch and either a manual or hydraulic throwout and a 621 bell housing. To buy all these parts new, you're in it for about $600.

The problem with the M22 is that you'll have no overdrive. Probably be great around town but limited on the freeway. If all you're doing is in-town driving it'd be alright.

As far as the engine goes, there's nothing cheaper (IMO) than a junkyard LS truck motor. The probability that you could put a new oil pump, front and rear seals and run that 170K 5.3L motor for another 100K is pretty good. An old-school 350 with that many miles will be pretty much trashed. The only way to know if you've got a good one is to build it yourself, and then you get into serious money.

Unless you're really in to nostalgia, I don't know why anybody wouldn't run the stock fuel injection. Reworking the harness to stand alone isn't very hard, just time consuming, and getting the VATS out of the way isn't much of a challenge either. An intake, carb, ignition control box and transmission control (if you stay with the 4L60/80) make carburation a pretty expensive option. I don't see going this way 'for the ease of it'

Remember, opinions are like bellybuttons, everybody's got one - this just happens to be mine.

[e015475]

And LS1Tech is an excellent resource, like Killer Bee says. Check out the 'Conversions and Hybrids' section.

There's some good write-ups on transmission options on this site too.

[mr48chev]

I've got to agree with E015475 in that converting an LS engine to carb defeats one the purposes of having an LS in the first place and will be disappointing in the long run. I know the carb only guys will argue but the simple ease of starting in any weather, fuel economy and overall performance will suffer with the swap.

Trans wise you are going to want no steeper than 3.5 gears with the Muncie if you plan serous road trips You can check the tire, gear ratio RPM charts for that and figure out what the difference in rpm at road speed would be.

^^ On a side note on the engine rpm/speed/ cost on a road trip to Kansas and Texas a couple of years ago we hit the states with 80 mph speed limits and figured out that the difference between running 74/5 and 80 was 5 mpg. Lots of cars passed us Wyoming but we stopped at less gas stations

[Hampshire]

SBC and manual trans ain't cheap. LS and manual costs less, but you will find (per e015475) that the manual trans can be $$. The LS option with a manual would be more budget friendly (than an SBC) with good power (yes, avoid a carb), economy & so on...

...However, when you do your research you will see why the LS/4L60/80 works for so many people here. It's about availability, price, performance and bang for the buck - plus the experience of many on this forum who go that route. That can be pretty compelling.

SBC and manual is old school feel. I like it, but it isn't for everyone these days (and it's $$).

[mongocanfly]

I don't have much to ad...no to a carbd LS..if you've got the 4l80 I'd keep it and run it...you can freshen up the LS if your worried about it...I put a nv4500 behind my LS with AA parts...cost about the same as a 4l80 and controllers...

[1project2many]

An old-school 350 with that many miles will be pretty much trashed.

More technically, a carbureted 350 with that many miles is much more likely to be trashed. Fuel injected engines have much better fuel control and tend to live much longer.

[Mains52]

Thanks guys I’m looking for experiences from fellow builders.

[robertsjm711]

I have a 5.3 with a M20, I wanted the wider gear ratio. Picked it up a the Portland swap meet for $5-600 (?) couple years ago. W/o trans, I have ~$400.

http://67-72chevytrucks.com/vboard/s...5&postcount=35

Part Part Number Price Supplier
Sachs Flywheel LS 4.8 or 6.0 NFW1050 $73.04 Rock Auto
Pressure Plate bolts ARP LS ARP-134-2201 $17.65 Summit
Flywheel bolts ARP LS ARP-330-2802 $32.10 Summit
Throw-out bearing remote hose kit HRE-8287 $35.95 Summit
Howe Hydraulic throw-out bearing HRE-82870 $130.00 Summit
Clutch kit 11" ~70's BBC LUK-04-049 $88.75 Summit
LS Pilot bearing 4.8 or 6.0 ADO-CT1082 $11.95 Summit

[robertsjm711]

Oh, and the shifter, mounting plate, linkages, bushings... can get spendy if you go Hurst - could be cheaper used, I got mine from eBay, swap meets, etc.

And that M22 rockcrusher are wicked strong, valuable and loud (wicked awesome IMO), but do have a close ratio. May limit drivability depending on how you want to use your rig.

[OrrieG]

Originally Posted by robertsjm711

And that M22 rockcrusher are wicked strong, valuable and loud (wicked awesome IMO), but do have a close ratio. May limit drivability depending on how you want to use your rig.

And as a daily drive the gear whine can get annoying. And no overdrive so highway driving will have the same rpm issues as any 1:1 ratio trans, manual or auto.

[robertsjm711]

True that whine can get annoying, but I like it. Probably wouldn’t on a daily driver. And in Oregon the speed limits are pretty low, so a 1:1 can work. I wanted a t56, but couldn’t justify the cost for another gear.

[e015475]

robertsjm711

Has the Howe hydraulic throw out bearing worked well for you?

You'd probably want to add a bellhousing to your list. There's lots of Chinese stuff out their, but Keisler/Silver Star or whatever they are calling themselves these days makes one for about $250 that they say is cast in the USA

[robertsjm711]

Originally Posted by e015475

robertsjm711

Has the Howe hydraulic throw out bearing worked well for you?

You'd probably want to add a bellhousing to your list. There's lots of Chinese stuff out their, but Keisler/Silver Star or whatever they are calling themselves these days makes one for about $250 that they say is cast in the USA

I haven’t used it yet, actually just installed it a couple days ago. Many of the articles I read about mechanical to hydraulic (non racing) conversions used this one so I went for it.
I have an old truck housing that I got cheap (swap meet, maybe a pattern, or maybe a problem?) and an adapter ring to compensate for the larger truck bearing retainer, $30-50 total). I looked at those aftermarket ones, and they were very nice, but I won’t be running high horsepower and was ok with a good old GM ugly one.