It's 5.3/AW4 swap time for the road racer

[IXNAYXJ]

The LM isn't the rest of the LSx series is all aluminum, at least that's my understanding.

Most of the Gen III truck engines have cast iron blocks, with exceptions here and there (LM4, L33 and L76).

 

[vetteboy]

If it'd help, I've got several blueprints for the small block Chevy and AMC bellhousing patterns.

 

[IXNAYXJ]

If it'd help, I've got several blueprints for the small block Chevy and AMC bellhousing patterns.

Thanks, but I think we've got it figured out. The plan is to use the GM bell housing and flex plate, then just adapt the AW4 torque converter to the GM flex plate.

-Matt

 

[Vanimal]

how are you making the adapter for the trans-bellhousing?

 

[IXNAYXJ]

how are you making the adapter for the trans-bellhousing?

We have access to a big cnc machine so we will be able to play around with stuff. We're in the parts acquiring stage right now, we're not even going to pull the 4.0 out for a couple months. We have a spare 2WD AW4 sitting next to the 5.3 in the shop, so it's just a matter of mocking it up.

-Matt

 

[streetxj]

Do you mean internal modifications? No, it's totally stock, 211k miles (~10k race miles) and we've never even changed the fluid. We do have a pretty decent sized cooler on it, seems to have been working.

If you mean shift controller, then yes. We're running a prototype RADesigns R/T Shifter that both mechanically shifts (PRN432) and shifts the solenoids at the same time. The TCU is completely bypassed, no TC lockup, etc. Watch this video to see it in operation:

http://www.youtube.com/watch?v=4HO4pRoQxbw&list=UUq4NnY-jLWUr5G1OPu7PbWg&index=2&feature=plcp

-Matt

Cool. What I meant about the shift kit is if the valvebody has any mods that make the shifts quicker and firmer than factory. Anyways, I was also wondering about the shifter you were using. Thanks for answering that question. I just think the shift kit or shift improver kit would make your shifts quicker when you manually shift it with the prototype shifter you are using. It will also help your transmission handle the extra power and keep the temps down due to creating less clutch slippage. The firmer shifts basically makes the clutches engage quicker and not slowly like factory. That slippage is what makes the "smooth" shifts.

 

[IXNAYXJ]

Yeah, we've thought about it. The quicker shift aspect isn't that big of a deal to us, we're racing over a 24 hour period, so a fraction of a second is irrelevant. But we might look into it if we start having heat-induced reliability problems. I'd rather not have to open it up if at all possible; slush boxes scare me. As it is, we're probably going to add another trans cooler for good measure.

-Matt

 

[Vanimal]

im sure you got your plan but i'm just wondering how you can have a thick enough adapter to have much structural integrity while still having the TC clear the inside/backside of the bellhousing. the TC needs to be engaged about the same depth into the front pump as stock.
what trans are you getting the sbc bellhousing from?
not being critical, more curious than anything.

i may be able to get you a blank bellhousing for a decent price. maybe even one with a sbc pattern and no trans pattern

 

[vetteboy]

Thanks, but I think we've got it figured out. The plan is to use the GM bell housing and flex plate, then just adapt the AW4 torque converter to the GM flex plate.

-Matt

What GM trans has a modular bellhousing that you'd be able to adapt the AW4 case to? Or are ya using an older 4-bolt manual trans belhousing?

 

[Vanimal]

What GM trans has a modular bellhousing that you'd be able to adapt the AW4 case to? Or are ya using an older 4-bolt manual trans belhousing?

i was wondering that myself. i dont think a manual trans bellhousing will clear the TC but then again i never measured one.

 

[Vanimal]

looks like the 4l60e has a removable bellhousing.

 

[shortxjdoug]

Jw could probably make an ultra bell for it.... probably wayy out of your price range though.


AW4 should hold up fine.... it sits behind lexus 1uz,2uz, and 2jz toyo motors and takes a beating just fine

 

[IXNAYXJ]

So the idea is to use an LSx bellhousing (we have a T-56 currently) and build our own adapter (say 3/4" plate) to bolt to the AW4, and the adapter that mates the torque converter to the LSx flex plate will be of equal thickness. We haven't measured if the AW4 TC will fit when moved, but we're assuming it will. If not, We'll just have to use a bigger plate of aluminum and adapt the AW4 bell to the back of the LS block.

Once we have all the bits and pieces and start playing 'automotive legos' things should sort themselves out.

-Matt

 

[Vanimal]

the spacer between the trans and bellhousing and between the TC and flexplate are unlikely to be the same thickness. there are WAY too many variables, especially if you're going to use a manual trans bellhousing. easiest way to measure this is to take off the aw4 from the bellhousing, bolt it up to a motor and measure from the trans mounting surface of the bellhousing to the mounting surface of the flex plate. do the same for whatever bellhousing you're going to use bolted to the 5.3. add the thickness of the trans adapter plate to the dimension you got from the 5.3 setup and subtract the aw4/4.0 dimensions from that sum. this will give you the flexplate spacer thickness you need.
i'd be very suprised if you have enough clearance in the bellhousing for the torque converter using anywhere near a 3/4" thick adapter. a manual trans bellhousing is likely to have even less room than an automatic bellhousing, and even then, i've never seen a trans bellhousing that had more than a half inch or so of clearance behind the TC before it made contact.


you have a few obsticals to overcome with this, interested to see how it pans out. easiest way would be to use a gm trans i think. you may be able to integrate your aw4 shifter into the 4l60e, however that is only a guess. i'm not sure exactly you'd have to manage the TC lockup or anything like that.

 

[Gold Cobra]

I've really enjoyed following your on-road racing with the Cherokee. Reading your article about your oiling problems and solutions was very interesting. I think the 5.3 is a great choice for an engine swap and is a great all around motor. I am disappointed though that your swapping out the 4.0 in your XJ. Endurance road racing with a 4 litre was what I was interested in. So the only Cherokee drivetrain left will be the AW4? Not exactly a Cherokee anymore.

 

[IXNAYXJ]

easiest way to measure this is to take off the aw4 from the bellhousing, bolt it up to a motor and measure from the trans mounting surface of the bellhousing to the mounting surface of the flex plate. do the same for whatever bellhousing you're going to use bolted to the 5.3. add the thickness of the trans adapter plate to the dimension you got from the 5.3 setup and subtract the aw4/4.0 dimensions from that sum. this will give you the flexplate spacer thickness you need.

That's kinda what I meant, I just wasn't clear. The two spacers/adapters probably won't be the same thickness, I was just using round numbers for the sake of simplicity. We really don't know what the final product is going to turn out to be until we get some serious Cardboard Aided Design, followed by some real CAD/CAM work.

you have a few obsticals to overcome with this, interested to see how it pans out. easiest way would be to use a gm trans i think. you may be able to integrate your aw4 shifter into the 4l60e, however that is only a guess. i'm not sure exactly you'd have to manage the TC lockup or anything like that.

Yes, we have a couple challenges, (some which I haven't mentioned yet) but part of the fun is figuring it out. Yes, the easiest (by FAR) way to do this would be use a 2WD 4L60e, but that puts us out of our budget (though if this doesn't work, we'll probably go that route). And I really want to see if the AW4 will hold up, because every non-Cherokee person said it's hopeless. I want to prove them wrong.

I've really enjoyed following your on-road racing with the Cherokee. Reading your article about your oiling problems and solutions was very interesting. I think the 5.3 is a great choice for an engine swap and is a great all around motor. I am disappointed though that your swapping out the 4.0 in your XJ. Endurance road racing with a 4 litre was what I was interested in.

Thanks! I, too, am bummed that we can't make the 4.0 work. We have every bolt on upgrade possible (99+ intake, ported H.O. head, HO fuel rail, bored TB, header, 2.5" exhaust w/ no cat into a Cherry Bomb, bigger injectors, cold air intake, etc) and we still are barely making 130 hp at the rear tires. We're just not competitive for the win using the 4-point-slow. It's really, really, really frustrating setting up a pass for three laps only to have the guy drive right by you on the next straight. After 13 races, 10k+ race miles and 3 years I think we've learned all we can about the 4.0 within our imposed budget constraints. On the Team /Petty Cash Racing 4643 KOH car the Bishop/Buell Racing 4.7 stroker is insanely awesome, but was also mucho expensive. And after our 505 Performance stroker blew a piston out of the side of the block after 2.5 hours, I'm unwilling to go down that road again.

So the only Cherokee drivetrain left will be the AW4? Not exactly a Cherokee anymore.

The AW4 and the beam axle are still original! And the unibody! Really, we haven't changed any more than many people do here with armor, bigger axles, etc. It's still very much a Cherokee in my mind; if it isn't then a lot of rigs on wouldn't qualify either.

-Matt

 

[vetteboy]

I don't know how your budget or time constraints are, but Novak makes that adapter plate already:

http://www.novak-adapt.com/catalog/kit_375.htm

Might take a little figuring to use it with an automatic, but the bellhousing part would match up.

When I did my bellhousing adapter:

(irrelevant, but Ford Taurus SHO to Jeep NSG370)

I paid $179 for the piece of aluminum, 12" x 18" x 1.25" 6061-T6 from speedymetals.com.

Good luck with it either way, lemme know if you want those blueprints. Lookin forward to seeing what you guys come up with.

 

[98cherokeedriver]

Not to derail the thread, but vetteboy, do you have any more info on the Jeep/SHO project somewhere else? I have a 94 SHO and I've thought a lot about what I could swap it into.

I also raced one once in a chumpcar race, awesome motor, takes tons of abuse. Unfortunately the rest of the car can be temperamental.

 

[IXNAYXJ]

Re: It's 5.3/AW4 swap time for the road racer-UPDATE!

So...update.

We bought a 4L60E bellhousing that fits the AW4 torque converter (the T-56 bellhousing did not) for $20 and designed an adapter that will fit on a 12"x12" plate of aluminum. A local machine shop that does a lot of work for Boeing and has some free CNC machine time and a scrap of aluminum they're willing to donate. Here's the motor and trans getting to know each other:

Luckily our crew chief is a prototype engineer for a company that does a lot of work with aluminum and whipped this up to get CNC'd:

We're also working on some prototype LSX-to-XJ pieces with well known motor mount specialists. The project is on pace to have it running by the time I get back from King of the Hammers. A local circle track has agreed to let us do some of our initial shake down testing there, so hopefully it'll be under it's own steam and burning rubber by mid February. Our first race with this new set up is March 23-24 at Sears Point/Sonoma/Infineon.

Sorry for the shitty pics, more (better ones) to come soon.

-Matt

 

[kastein]

Subscribed... looks like you aren't screwing around or going halfway on the adapters!

Will the 4L60E bell fit the AW4 TQ far enough back to engage the oil pump and splines correctly? How are you going to keep the AW4 pilot properly centered on the crank/trans rotational axis? Some sort of custom spacer/bushing setup?