What's the Most Popular V6 Engine for Light Weight Crawlers Currently?

[Sean]

Some bushplane folks are starting to use the Yamaha snowmobile engine. They weigh almost nothing,are compact,reliable and make 150bhp stock. I forget the model but the later ones are injected. They're also supported by the aftermarket from stand alone harness to 300+ turbo. Too loud wide open in a plane but probably perfect for a little two seat moon buggie. So light you can pick it up and walk around with it.

Sounds like the supercharged Yamaha engine in my Lotus almost.

 

[BustedCrank]

Well if we're gonna go off on a tangent, there's the supercharged rotax engine in the seadoo that's rated at 300hp.

 

[arse_sidewards]

Well if we're gonna go off on a tangent, there's the supercharged rotax engine in the seadoo that's rated at 300hp.

Marine 2-stroke shit is fucking wild like that.

There's probably NA outboards that are making 250 for same weight and 350 for 50lb more once you remove the weight of all the lower shit.

I'm pretty sure larboc is an emissions engineer for Mercury and probably has better recommendations.

 

[JohnnyJ]

It's too bad none of the GM 60° V6 High Feature LFX, LFY, LGX or LGZ engines have adapters to older GM longitudinal transmissions. Finding 14K-29K mile engines in junkyards for $1400-1900 locally. Over 300 hp with close to 300 ft-lbs (289ish).

Are they different than the standard gm 60*?

You might have to go to the old place, but Jesse Haines (mudtruck44) used the 3.9 on a few builds. I thought he used the TF904 from XJ or something like that, which I think was common to the GM 60* V6. Or he's somewhat active on faceagram and likely would answer.

 

[Sean]

Well if we're gonna go off on a tangent, there's the supercharged rotax engine in the seadoo that's rated at 300hp.

Jesus....like I need more distractions, lol.

 

[Sean]

Well, it looks like I may be coming full circle on this whole thing.

So this:

is the 4.3L LV1/LV3

And this is a 5.3L LS with an Fbody oil pan (which I already have):

Seems to me, as someone mentioned earlier in the thread, a 5.3L L83 would save weight with the block and be roughly this same size which is only 2.25" longer than the hard to find 4.3L LV1/3. Wiring/tuning an L83 would be far easier, rebuilt engines with long warranties aren't crazy expensive and you can get all kinds of aftermarket support for them.

 

[Bebop]

Good that you see the light

 

[Sean]

Good that you see the light

And to be honest, your comments have greatly influenced the decision. Thank you.

 

[Bebop]

And to be honest, your comments have greatly influenced the decision. Thank you.

I'm all for a lightweight V6. Makes a ton of sense for a little crawler.
But you keep bringing ease of install / budget back in the convo and nothing will ever beat an LS in that department.
And an LS unit is marginally bigger/heavier.


Look into the Haltech Rebel LS ECU for your needs. Best new product of 2023.

 

[Sean]

I'm all for a lightweight V6. Makes a ton of sense for a little crawler.
But you keep bringing ease of install / budget back in the convo and nothing will ever beat an LS in that department.
And an LS unit is marginally bigger/heavier.


Look into the Haltech Rebel LS ECU for your needs. Best new product of 2023.

If I was smarter and more knowledgeable, I'd want to go lightweight V6, but I know I don't know shit about this so it makes a lot more sense to go the path of least resistance (or most commonly taken).

Will do on the ECU....I've often heard it's best to get the engine with the computer and harness....not sure if that's still the case?

 

[Bebop]

Will do on the ECU....I've often heard it's best to get the engine with the computer and harness....not sure if that's still the case?

If you buy used and want to run a OEM ECU, then yeah, get all from same vehicle.

If you want to buy a new engine, get a standalone and a good tuner.

 

[Ghetto Fab.]

Yup, there is a reason they are so common in swaps. Its really hard to beat that package. Anything that is smaller, or lighter will need more $$$ thrown at it or custom parts(more $$$), and anything that makes more power is likely to be larger in size and more $$$.

 

[chaplinfj60]

you will not be disappointed at all with the LS platform. it deliverers lots of smiles per mile.... and you can just about do anything to them, if i recall they have 6 bolts per main bearing. nuts how much the low end can spin and stay together.

 

[Sean]

Okay, so I already have two 2001 (Gen III) fairly low mileage LSX cast iron block 5.3s with the low profile car intakes and one has the Fbody oil pan to shrink them up size wise.

I'm assuming I cannot use these Gen III "LSX" 5.3s as mock up engines for a Gen IV or V 5.3L, correct?

It would be really nice to be able to build around what I have and then when I'm actually all put together swap it for a newly rebuilt engine with at least some sort of warranty but I'm guessing that the engines are just different enough that motor mounts could be in different spots, exhaust ports and where accessories can actually mount to the block may be slightly or even drastically different as well as likely slight differences in intake height and oil pan dimensions.

 

[Bebop]

I'm assuming I cannot use these Gen III "LSX" 5.3s as mock up engines for a Gen IV or V 5.3L, correct?.

Yes you can, they're exactly the same, short of some minor wiring differences.

5.3 gen3 to gen4 are the same.
6.0 gen3 to gen4 have a different car intake, which is close but not identical.



Gen5 shit is all different.

 

[Ghetto Fab.]

So why not just run what you have, since you already have it?

 

[Bebop]

So why not just run what you have, since you already have it?

Makes too much sense

 

[Sean]

So why not just run what you have, since you already have it?

At this point, I'm mainly trying to reduce weight and I can always use these 2 engines on other stuff.

 

[Sean]

Makes too much sense

Says the same guy who belittled those very same engines when I mentioned I was using them for my portal cars in the first place....which is what generated this thread.

 

[Bebop]

Says the same guy who belittled those very same engines when I mentioned I was using them for my portal cars in the first place....which is what generated this thread.

Hey, you have 2 opposite goals.

 

[Sean]

Hey, you have 2 opposite goals.

Agreed, to an extent. Lighter and smaller would be better. To me, anything 4K or under without passengers is a win. Can I get there with an aluminum LSX, TH400 and Hero 3 speed (or Behemoth D300 maybe) and portal 9s with 42" reds or Milestars? Maybe....but it won't be easy and I realize that.

And I didn't mean to come off as harsh with that comment about your comments sending off in search of a lighter combo. That was a good exercise in analyzing the cost to benefit. Apologies.

 

[Bebop]

Agreed, to an extent. Lighter and smaller would be better. To me, anything 4K or under without passengers is a win. Can I get there with an aluminum LSX, TH400 and Hero 3 speed (or Behemoth D300 maybe) and portal 9s with 42" reds or Milestars? Maybe....but it won't be easy and I realize that.

And I didn't mean to come off as harsh with that comment about your comments sending off in search of a lighter combo. That was a good exercise in analyzing the cost to benefit. Apologies.

No need to apologize, I just want to make sure you understand why I explained both options.
The topic started in a direction that made me think you wanted to go lighter/smaller even if it cost you more money and headache.
Later in the thread I realized that you didn't.

Just sell your 400 and Hero and go for a 350 and Atlas and you're gonna save weight and room. Keep the 5.3 for now. You can swap an AL long block at any time, takes a weekend.

 

[Sean]

I appreciate your opinion and advice and I don't mean to sound contrary, but the TH400 is only 15 lbs heavier than the TH350. The Atlas 2 speed I have now was 115 lbs IIRC with the flanges on it, so I'm not saving much (35 lbs) and give up a useable 2.5:1 in the 3 speed Hero. If I were going to swap the cases, I think I'd go D300...since it cuts 78 lbs over the Heroes I have and is about 2" shorter overall (in height) so the belly could be smaller by an inch.

For reliability/durability/versatility I feel like the 50 lb trade off (in tranny/tcase) is worth it. Lord knows I could stand to lose 20 lbs myself to offset some of it, lol.

But yeah, one really attractive feature is I can build around these iron block engines now and swap to aluminum block ones before they are completed.

 

[chaplinfj60]

the th350 is alos a bit shorter. i think 2-3 inches that may help too.

 

[Bebop]

For reliability/durability/versatility I feel like the 50 lb trade off (in tranny/tcase) is worth it.

Not with a 5.3
You'd be shaving 50lbs with no drawbacks.

Again, just my 2cts.

 

[Sean]

the th350 is alos a bit shorter. i think 2-3 inches that may help too.

I think I'm okay on length even with the TH400....the weak tail housing on the 350 makes me question it, though I think proper mounting goes a long way towards that failure point.

 

[Sean]

Not with a 5.3
You'd be shaving 50lbs with no drawbacks.

Again, just my 2cts.

Fair point. I do tend to lean towards overkill which means stuff ends up heavier than it needs to be.

 

[SMI17]

Is the Hero 3spd still available?

 

[Sean]

Is the Hero 3spd still available?

I think you can still order it from Phenom....though I don't know b/c their site isn't really up to date and they do a lot through IG now I think. They've been mostly focused on 2 speed cases. Phenom Transfer Case

 

[SMI17]

Ok cool thanks!