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Keith
Keith GRM+ Memberand SuperDork
8/28/08 9:08 a.m.

Lemme tell you, an LS-powered Miata is a bit of a change. I could learn to like this - it has such a flat torque curve that it hides its performance unless you have some sort of point of reference. It's faster than it feels. Kinda the opposite of a stock Miata then.

I'm looking at various options that are out there. GM Performance Parts has some good prices with full warranties, which is great for the higher-end builds. But I'm also looking for more budget options, and a few people have suggested the 5.3. Looking through my options, it appears the L33 is the pick - it's the HO version found in a few extended-cab trucks. It's also pretty easy to find in junkyards for good prices. Any comments on this motor? Does it drive like a truck motor, or does it like to be wound out? It's oversquare, that's a good sign.

John Brown
John Brown GRM+ Memberand SuperDork
8/28/08 9:18 a.m.

For low budget entries look at the 4.8L there is an alloy 5.3L as well and don't forget the Corvette/GTO 5.7L and the lovely 6.0L.

joey48442
joey48442 Dork
8/28/08 9:33 a.m.

But wouldnt the one they put in the truck be a cast iron block? I thought that I read they developed the cast iron ones for truck use.

Joey

bluej
bluej Reader
8/28/08 9:39 a.m.

most are, some aren't. http://en.wikipedia.org/wiki/GM_Vortec_engine#V8 not the best source, but gives you an idea.

P71
P71 GRM+ Memberand Reader
8/28/08 9:58 a.m.

I don't claim to be an expert, but I have been shopping around for an LS motor for an eventual swap.

The 4.8 uses some different parts then all of the rest and should generally be avoided.

The 5.3 comes in 3 flavors. The iron-block truck motor (175lbs heavier then the aluminum one), the aluminum-block truck motor (including the first year SSR), and the FWD setup LS4 that makes 303HP ECU-Limited in the last round of SS Impala's and Grand Prix GXP's. Obviously stay away from the FWD setup ones. There's a few different HP levels on the truck versions, but not enough to make a difference. GM made some huge number of these already and this is generally the route I'm looking at taking.

The 5.7 is the "original" LS1. All 3rd and 4th Gen GM V8's are called "LS" motors, even if they aren't acronymed "LS" (think LM4, LQ4, whatever). The 5.7 came in the C5 Vette and the 4th Gen F-Body Firebird and Camaros (98-02). Also found in the 2004 GTO (regular throttle cable). The 405HP LS6 version was found in the C5 Z06 and the first round of Caddy CTS-V's. I'm pretty sure there were some truck motors and iron blocks too, but they'd all be pre-05. I didn't really look very hard at the real LS1/LS6 because they go for stupid money compared to the non-LS named ones. Good points are you can find a take out with a T56 6-Speed already attached.

The 6.0 is the "Heavy Duty" truck motor and is also available in iron or aluminum block. Also found in the first round of C6 Vette (05-07 I think) and the 05 and 06 GTO (LS2, 400HP/400TQ, drive-by-wire throttle). Found in the 2nd iteration Caddy CTS-V as well. This is the current swap king as everybody wants the GTO takeouts (T56 6-Speed or a traditional 4-Speed Auto, good for drag racing). The drive-by-wire stuff gets amusing (you'll need the pedal assembly and if you get the auto the shifter too). Luckily aftermarket larger throttle bodies bolt up so us non-ECU trusting people can use a cable. A non-LS designated 6.0 is also used in the new G8 GT (360HP or round-abouts).

The LS3 is the new "big dog" and is currently available in the C6 Vette only (430/436HP depending on exhaust ordered). It should be making an appearance in the Camaro and G8 GXP. Supposedly it can be setup with a good displacement-on-demand.

Then of course there's the 7.0 LS7 which is truly awesome, and very out of my reach.

Things to watch out for is that Gen3 to Gen4 changed the number of teeth on the reluctor wheel, so you have to stick with all the electronics from one or the other. There's a few different accessory drives (Vette, F-Body, Truck, GTO) so watch out what will fit in your bay. Truck intakes are huge but the car intake drops right in, it's just not compatible with the truck accessory drive IIRC.

If you really want to get into the nuts-and-bolts of JY LS stuff pick up the last few years of Car Craft, They did a 400HP 5.3 for stupid cheap (got the complete motor for $550!) and built a 600HP 6.0 and have had great articles on what to look for when buying a JY one.

Hope that helps!

Keith
Keith GRM+ Memberand SuperDork
8/28/08 10:20 a.m.

The L33 in question is an aluminum block 5.3, the "high output" version that's used in 4WD applications - specifically, 2005+ Silverado/Sierra extended cabs. 310 hp, 325 "torques". There's an engine in Montana with 38k for $600, for example.

We swapped the accessory drive on our LS1 for an LS2 setup to gain 3/4" at the front of the motor. No worries there.

I'm starting to get familiar with LS1, LS6, LS2, LS7, LS3 etc and I'm putting together a spreadsheet of expected build costs with them (http://www.flyinmiata.com/V8/costs.php) using new engines from GM. You can actually buy complete ECUs that even come with a new throttle cable for the DBW setups :) But a few people suggested the 5.3 because of how it drives, and I was curious if there was any input from this group about how it feels. Is it revvy or is it a dog? So far, my reading indicates it's the real bang for the buck.

It's far cooler to say "My Miata has a Corvette engine" than to say "My Miata has a Silverado engine", but if it's the value king then I'm willing to make that sacrifice :)

walterj
walterj HalfDork
8/28/08 10:29 a.m.

What manual transmission options are available? The T-56 seems pretty expensive at junkyard prices. For the engine costs we are kicking around here... $600!? I could see sliding one into my E30 but its a non-street legal race car that needs to have a durable trans that can handle the HP.

AngryCorvair
AngryCorvair GRM+ Memberand HalfDork
8/28/08 10:33 a.m.

there's a board member called "Gen3V8Underhood" or something like that. He's used the L33 in several swaps and proclaims undying devotion to it.

P71
P71 GRM+ Memberand Reader
8/28/08 10:57 a.m.

All Gen 1/2 GM V8 trans will bolt to Gen3/4 engines

The L33 is a very good choice, that's the one I'm looking at. Technically it's an "SSR" motor, but if you throw Corvette FRC's on it nobody would now the difference anyways. I drove a truck with one and it was impressive at 5,000Lbs, so I think it would be awesome in a Miata!

The other one I was looking at is the 6.0 aluminum setup from the 1500HD and 2500 Silverado/Sierra. The "VortecMAX" version has some crazy HP #, but all of them are basically a cam swap away from 425+ HP. Also it was available with a super heavy-duty 4-speed or even 6-speed auto (4L80E and 6L80E I think...). You can guess from there about why I'd want an auto and what car it's going in...

Also, I forgot to mention that on the GTO accessory drives you may want to heat shield the snot out of the power steering pump. They are starting to have a rash of failures and they are VERY expensive!

Keith
Keith GRM+ Memberand SuperDork
8/28/08 11:21 a.m.

Actually, we're using a factory Miata PS pump. Cheap :)

P71
P71 GRM+ Memberand Reader
8/28/08 12:19 p.m.

That's a good idea to stick with the OE pump for the OE rack.

SoloSonett
SoloSonett Reader
8/28/08 12:28 p.m.

I'm using a powered Miata rack in my new Sonett re-build. Anyone have any issues with a Delco ( stock ) Camaro pump with one?

stuart in mn
stuart in mn Dork
8/28/08 12:32 p.m.

Hot Rod magazine this month has a crate motor test with several LS engines, you may want to check that out.

neon4891
neon4891 Dork
8/28/08 12:39 p.m.

even in the smaller iron blocks, a cam and intake swap will go past 400 HP and be streetable.

Dr. Hess
Dr. Hess SuperDork
8/28/08 12:46 p.m.

My friend has a 99 Camero SS with aftermarket heads, big cam and 480+ HP at the wheels. It's been tuned better since that dyno run. He also has a 06 or 07 SUV (forget the name, it's the one advertised on the sports channels, Yukon?) with the LSx V8 in it, all stock. I drove it dropping him off at the hotrod shop that was fixing the grenaded lifter in the Camero, and that thing certainly has some torque. If you could get that motor for six bills, that's a bargain. I still prefer the 1uzfe, but that SBC has always been GM's best product, and you can't beat the availability, transmission assortment and aftermarket support.

Someday, we're gonna be like on Mad Max: "That's the last of the V8's."

Keith
Keith GRM+ Memberand SuperDork
8/28/08 1:00 p.m.

Thanks Stuart, I will.

dyintorace
dyintorace GRM+ Memberand HalfDork
8/28/08 1:31 p.m.

Keith, angrycorvair is right. There is a board member who regularly swaps the 5.3L engine into anything (my personal favorite is the BMW wagon ) and swears by it.

Per his profile, this is his website: http://www.fquick.com/Swap_A_Holic

He should be able to answer many of your questions.

Keith
Keith GRM+ Memberand SuperDork
8/28/08 3:28 p.m.

Sweet, thanks. I've come across that RX7 a few times in my searches of the tubes, actually.

So the BMW has the L33 engine with a turbo. L33t!

kreb
kreb GRM+ Memberand Dork
8/28/08 3:58 p.m.

I've never understood why one needs a 6-speed on a motor with such a wide powerband. Would an LS blow up a T-5, or would that be a swap worth considering?

Keith
Keith GRM+ Memberand SuperDork
8/28/08 4:24 p.m.

The T56 is stronger than the T5 from what I understand, although I'll let the GM experts discuss that in detail. I agree that 6 speeds does seem a little ridiculous in this particular car, but the ultra-tall 6th gear is going to turn this into a really relaxed highway cruiser. Even with the "short" final drive, we're looking at 2000 rpm at 80 mph.

When driving the car yesterday, I found I was using about 80% of the gears in the box at any given time as I skipped around.

Travis_K
Travis_K Reader
8/28/08 5:32 p.m.

I am probably going to swap an LS engine into my 1970 chevy pickup when I can find one that I can get from pick and pull for $150 ( they are starting to show up, i just havent been quick enough yet to find one that isnt burned before someone gets it). I dont really know about the newer ones, but I know the 5.3 and 6.0 truck engines have a cast iron block, but there was an aluminum 5.3 ( in the SSR). There are 2 different 6.0 engines (before the ls2 came out) one high performance one (hummer, escalade, silverado ss, etc) and one regular one. Even the T56 isnt terribly strong, GM used cheaper parts in it, and people upgrade them with stuff from the viper. The GM T5 isnt even strong enough for the TPI 350 in the 3rd gen camaros, but what about the super T10 from the 2nd gen F-bodies? I dont know if it ill fit, but its a 4 speed and its stronger than the T5.

belteshazzar
belteshazzar Dork
8/28/08 5:35 p.m.

if 6th is 1:.5 or similar 4.10's don't hurt as much.

Travis_K
Travis_K Reader
8/28/08 6:34 p.m.

Does anyone know why so many LS engine trucks have burned? In the last couple years I have seen easily 100 of them in the junkyard that are totally burned ( i dont know if its a recall, or maybe it wasnt the trucks fauly and they had been donated to the fire department? or I dunno what). Its just odd to walk into the junkyard and see 30 or 40 burned GM pickups, hummers, tahoes, avalanches, etc. ANd I mean really burned, some of them with the heads dripped down the sides of the block.

YaNi
YaNi New Reader
8/28/08 8:04 p.m.
Keith wrote: The T56 is stronger than the T5 from what I understand, although I'll let the GM experts discuss that in detail.

The T5 is similar to the FC3S RX-7 N/A transmission, which is only good for about 250-300hp in the torqueless wonder.

P71
P71 GRM+ Memberand Reader
8/28/08 8:17 p.m.

kreb, The T-5 is actually a very weak. Even the Mustang 4.6's have Tremec's since the mid-90's (3550 or 3650 or something like that). 300 FtLbs is about the highest TQ a stock T-5 can handle. The T-56 is stronger and also has a huge overdrive in 6th (.5 to 1 as mentioned) which nets great fuel economy.

Travis, There are aluminum block 5.3 and 6.0 truck motors in the trucks. About 30-40% of all truck LS engines are actually aluminum block. (According to Hot Rod and Car Craft anyways, and they seem to know LS motors pretty well). As for the burning, the early 90's stuff had massive problems with fuel pump wiring harnesses, I'm wondering if GM is still having problems with it's electrical suppliers?

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