LS4 V8 Engine Swap

[bartmanS4]

You could always do a body lift. VXorado's rig has a lot of space to work with under there. I think he has a 4" body lift. Jon?

[Leon R]

That is an option, which could help, but VX is already too high for my liking, so I do not see myself doing this

[clipper 03 rodeo]

Just something to add, if you've noticed the intakes on the LS4 are "backwards" compared to normal engines, and we wouldn't have space to run an intake since it would be so close to the firewall. You can flip the intake around, but it would require you to relocate the power steering reservoir and possibly need a high rise intake manifold for it to clear the PS pulley and such.

[Leon R]

The Fiero guy that I listed above shows you how to flip the throttle body by using LS1(?) intake. I still think that starter clearance will be out biggest obstacle.

[clipper 03 rodeo]

Yeah I agree, and you can use an LS1 or LS6 intake on the LS4's, but still require a little modification to make them sit flat but it's easy and no big deal to get done. They flow quite a bit better so it's an easy power adder.

After researching I want to do this more and more haha. I'm just not sure if I should go the LS4 route (and have to deal with the starter stuff) or use the GM truck 5.3 V8 and just have an adapter made for the tranny.

[Leon R]

Adaptors can get messy (unless they already exist). Actually, adaptor for Fiero stock tranny should work for us .

[clipper 03 rodeo]

Very true, the only thing I don't know much about is flexplate spacing and if it would need modified. I did find a place online that actually makes custom adapter plates along with any spacers you may need. They say they can make an adapter for any engine/transmission combo out there pretty much, so I think i'll shoot them an e-mail and see what they can do.

It looks like it would be around $450 to have a custom one made for our application.

[Leon R]

Only, I would spend the extra coin and get LSx engine (all aluminum). Those truck motors have heavier iron blocks.

But honestly, lately I have been fascinated by the rear mounted turbo system, which BTW, can also be applied to the V8!

[BigSwede]

GREAT point! TOD would be disabled if I understand correctly. The VX or Trooper 5Speed computer is required to run it.

FWIW, 5-speed Troopers do not have the TOD transfer case.

In any case if I were you guys I would look at a different tranny than the 4L30E...

[Leon R]

FWIW, 5-speed Troopers do not have the TOD transfer case.

I know that it is a bit off topic, but what type of transfer case do they use?

[clipper 03 rodeo]

In any case if I were you guys I would look at a different tranny than the 4L30E...

My Rodeo doesn't have the 4L30E in it, mine has the better Aisin auto used in the 04 250hp Direct Injection Rodeo/Axioms. So I don't think i'll have any issues with it since it will only be about 50hp more than what the DI Rodeos came with.

[clipper 03 rodeo]

Well after chatting with some LS4 guys, they recommended I go ahead and use the GM 5.3L truck engine along with the matching tranny. Mainly because it would simplify the wiring greatly by being able to control the engine and trans from the single GM ECU instead of using a standalone system, it would cost quite a bit more and would require custom programming going that route. I was thinking maybe I could just use my Isuzu ECU to control the tranny alone and using the GM one to control the engine functions, but it seems like it's more complicated than to make everything work correctly.

So i'm thinking i'll just go the truck 5.3 route since it would be pretty easy for me since my Rodeo is only 2wd, the main thing i'd need is a custom length driveshaft and mounts to make this tranny work in my rig with the stock GM ECU.

P.S. The LH6 GM 5.3 V8 has an aluminum block, not iron compared to the LY5.

[Leon R]

I stand corrected on iron blocks, but what transfer case do the non-TOD cars use?

[BigSwede]

I know that it is a bit off topic, but what type of transfer case do they use?

I think the 98+ 5-speed Troopers use an Aisin, don't recall the number.

[BigSwede]

As another somewhat relevant side note, the reason the 98+ Troopers got the uprated modified 12-bolt axle was that Isuzu was planning a V8 for the Trooper. It was to be basically a 3.5L with 2 more cylinders, putting it at about 4.7L.