LS4 V8 Engine Swap

[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!

[Leon R]

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

[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.

[BigSwede]

No, they had a traditional part-time 4WD transfer case. Only auto tranny Troopers had the TOD transfer case.

[clipper 03 rodeo]

I got an e-mail back from the guys that make the custom engine adapters. It will be a little more expensive than I was thinking.

For an adapter to mate an Isuzu trans to a GM Vortec 5.3 it would be $850 for the first one and $550 for the next 3. I'd also need to send them the whole entire engine and transmission for them to make them.

Yeah I think i'll just ditch my Aisin and go ahead and swap in a 4L60e. After researching you can get a full swap wiring harness with fuses and a reprogrammed ECU for the Vortec 5.3 and 4L60e tranny for arond $750. That's not bad considering it already comes with a programmed ECU, you can get just the harness for around $500. It seems pretty expensive when I know you can just modify the stock harness for dirt cheap, but I like things super clean and simplified so I think it would be a good idea to get one.

[Leon R]

I thought I posted this before, but this is another method to add a starter to LS4:

http://forum.britishv8.org/read.php?6,37035