LS4 V8 Engine Swap

[Leon R]

I keep going to back to this being the best engine for VX V8 swap... Why is it better than others?

1. It has "GM Metric" bell housing bolt pattern, so it is a direct bolt up to the VX transmission.
2. It is CHEAP! The cheapest LS family engine you can get ($900-$1200)! Since it does not bolt up to the usual RWD GM transmissions, it isn't sought after by the "engine swap enthusiasts" who can't get enough LS(x) engines for swaps into just about EVERYTHING!
3. It has lower profile accessory drive/belt, which should be better suited for VX's engine bay (originally designed for a shorter V6).

Problems:
1. No one (to the best of my knowledge), had done this swap into VX
2. The block has no provisions for the starter (it is meant to be mounted on the transmission), so stock VX transmission will have to be modified to accept a starter (not a HUGE deal, assuming that we have clearance in the firewall/tranny tunnel area).
3. "Weakness" of VX transmission. I specifically want to STAY AWAY from this issue in this thread! I would like to get myself a 400hp VX and THEN I will deal with the transmission inadequacies. There are many methods of straightening automatic transmission, including replacing it with a 5sp ;).

I also found that Fiero guys also seem to like this engine:
http://www.fiero.nl/forum/Archives/Archive-000001/HTML/20130314-2-113207.html

Using his method, we can adapt a starter to a VX tranny:

http://i973.photobucket.com/albums/ae215/grndsm/LS4Startersolution_zpsdca261c8.jpg (http://s973.photobucket.com/user/grndsm/media/LS4Startersolution_zpsdca261c8.jpg.html)

But my first question, do we have enough clearance for the starter mounted above the tranny? If not, what resides on the inside? Can we intrude into the passenger compartment, without interfering with something critical?

[ND92]

I don't have any advice but I'd like to see how this works out. I'm thinking of a 5.7 hemi swap but of course that's a whole drive train mod.

[SilverBullet75]

One thing to seriously consider is the emissions laws for your area. My LQ4 project was scrapped because I wouldn't be able to meet all the rules set by DMV for vehicle recertification... No matter WHAT engine I used.
You can get the physical engine/engineering setup completed and end up having to scrap the project because you can't get it registered.

I hate how painful of a process it is here!

[Leon R]

Come on... There ways round rules like that ;). What SPECIFIC rule did your project violate? Usually, you can take advantage of inspector's general engine swap ignorance and slip thing through.

In Mass, vehicles older than 15 years old are exempt from emission testing. At best, they check for a CAT, but even that is rarely done. So I only have to worry about for couple of more years.

[SilverBullet75]

NV sucks for rules!
The issue was that the EVAP system has to be as it was from factory, on the vehicle that the engine came FROM.
It can't throw a CEL, and the EVAP can't be deleted by a tuner.
So, in order to get that to work, the gas tank from the donor vehicle would need to be transplanted into the VX with all EVAP systems attached and functional... BUT, the 2500HD (or any other vehicle that the LQ4 came in for that matter) has front to back gas tank along the frame rail... yeah... that's not gonna work.

So, my next idea was to try an FBody (Camaro, Firebird..) with LS1. Gas tank is "similar" in shape/size. In theory it could have worked... BUT, the killer of that one was finding out that the EVAP is tied electrically to the actual FUEL GAUGE in the dash of the FBody! (not just the sender).

I just need to move to a different state (or county) that doesn't have as tough of rules as Vegas (Clark Co.).

[Leon R]

The issue was that the EVAP system has to be as it was from factory, on the vehicle that the engine came FROM.
It can't throw a CEL, and the EVAP can't be deleted by a tuner.

Agreed! Pretty sure that this is a federal requirement for ALL states! What differs from state to state is the enforcement of such laws!



So, in order to get that to work, the gas tank from the donor vehicle would need to be transplanted into the VX with all EVAP systems attached and functional...

But this is where were we disagree :) Rules and regulations can be interpreted in many different ways (I am pretty sure that they made a profession out of this ;)). While your interpretation is correct, it is probably THE most difficult way of achieving desired effect!

Instead of transplanting an ENTIRE fuel system from the donor vehicle you need to understand how EVAP system works in the donor vehicle, compare it to VX's EVAP system and then figure out a way of making they play together! ;) Most of these systems work in a very similar manner, so a simple purge solenoid valve swap might do the trick! Considering that Isuzu used many GM parts, you might even find that the two are compatible.

The bottom line, you want to make GM computer happy and CE light free! There are MANY different ways of achieving this without transplanting 100% of emission controls from the donor vehicle (which is impossible!). Are they 100% legal in a full sense? Probably not, as they weren't designed by GM to work together. But no one is going to apply THAT level of scrutiny to your project!

Have you tried talking to others in your state, who have performed an engine swap?

[evillecutter]

would you have to drop the transmission to change a bad starter?

[Leon R]

Probably, but how often to you expect to change starters? :)

Something people do not realize about engine swaps, is that they are NOT up to the same quality as OEM designed parts! Things like:

- engine wiring
- motor mounts
- maintenance access
- under hood temperatures

Are typically less than ideal. That is why engine swaps should be done only if the rewards are enough to offset the negatives! And that will vary for each individual.

[SilverBullet75]

Yes, I talked to a couple tuning/mod shops actually. But the difference is that ALL of their customers that did a swap did it in an OLD vehicle that doesn't have the requirements applicable. None had done it in a '96+ vehicle where the rules are completely different.

I had thought about trying to fit the donor equipment to the VX as you said.
This might work. But, I don't have the knowledge required to do this.

Now, if you want to take point, PLEASE DO :yesgray:
I would love to start this project up again, but this time with an LS1/2/4!
(BTW... I too looked into the LS4. VERY interesting option.) :)

[bartmanS4]

Will it be possible to maintain the TOD or would this require a manual transfer case? I know the TOD has it's own computer but I have no idea how this interacts with the ECU. I think this would be a really cool swap and if not too complicated provide a good alternative to our standard power plants as they get older and older.

I my opinion the emissions standard should simply be: does the vehicle pass the individual output tests period. My guess based on, well nothing, would be that this would achieve a more efficient power plant solution resulting in lower emissions.

[SilverBullet75]

GREAT point! TOD would be disabled if I understand correctly. The VX or Trooper 5Speed computer is required to run it. In that case, wouldn't you be forced to go 5 speed anyway? Does the 4L30e receive input from the engine's computer?

[SilverBullet75]

Wait... I don't know WHAT I was thinking...
Scratch that last post.
The engine's computer doesn't control the TOD...

But, it does control the transmission, does it not? That's why there's two versions... Manual and Auto.

[Leon R]

I do not know how TOD works, but at the very minimum, I suspect that it receives a TPS signal. That can happen directly from the TPS sensor or from factory ECU.

Honestly, I think that TOD is neat, but I do not buy into a hype.

Is there a transfer case with conventional AWD option?

[clipper 03 rodeo]

Sounds awesome, keep us posted on what you end up doing and be sure to take tons of pics.

I'm really considering a swap like this on my 03 Rodeo if everything including the A/C can still be used. My Rodeo has the stronger Aisin automatic transmission, so it should hold up to the extra power pretty well since it's the same one used in the 250hp Direct Injector Rodeos/Axioms.

[Leon R]

I spent a couple of hours under my VX last couple of days, changing tranny oil/filter and I am pretty sure that there isn't enough clearance between the tranny and the tunnel. I believe that we would have to make clearance by going into the underdash area.

[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.

[Leon R]

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

What does it mean? Did it have a diff for "AWD mode"?

[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