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VW TDI into a 99 XJ

I get the town names confused up there... I checked a few places out in Royalston as well but they were just too far gone to even consider.

Let me know if you need a hand with the wiring at any point, I'm pretty decent with the Jeep end of things at the very least and have enough experience with electrical engineering stuff to get myself in trouble.
 
No progress at the moment. I ordered a gigantic new turbo that isn't likely to fit in the space provided. So I am working with a guy to try and make it fit. Likely a custom exhaust manifold and some praying. :)

The motor is heading to the VW guy to get pulled and re-prepped with a pile of new parts. Turbo, injectors, larger fuel pump, timing belt.

I am also 99% confident I am going to go to an electric steering pump. It will be a little more efficient and will allow me to move the A/C pump to the top of the motor. Plus the VW pump doesn't seem quite strong enough to power the Jeep rack. This will allow me to easily reclock the motor so there is no chance of the driver side control arm contacting the A/C compressor or the passenger side contacting the turbo if I leave it in the stock spot. Right now the turbo can get smacked.
 
Have you considered a biturbo setup? The idea is that the smaller turbine spins up faster (low inertia) and provides the low end boost whilst teh larger turbine is spooling up.

You find them on a number of Euro performance vehicles as well as the current "state of the art" big rigs.

You may be able to use a smaller "large" turbine and get the same effect. This is not the "twin" turbo setup that is commonly used on V engines. Those have each turbine feeding one bank. This is sequential boost.
 
I haven't honestly put any thought into a twin setup. Mainly because at this point that doesn't buy me much.

Twins don't really save me any space. And I am not seeking MORE power, yet. I have a Garrett GTB1756VK coming, which is a variable vane. The variable vane turbos tend to spool pretty well. Especially something "new tech" like the GTB. This isn't to say that a twin might not be better. But I am not sure that it's worth the headaches TODAY to engineer it in.

I am not going to pretend the Jeep won't spend 99% of it's time on pavement. Then it'll be logging roads and similar levels of off road difficulty. I slightly lack the wallet-testitude to take road legal vehicles and truly punish them. I have 4 wheelers and dirtbikes for that. So I doubt I need more power off idle. Plus, a STOCK TDI makes peak torque (~175 ft/lbs) starting at about 1600 rpm. With the new turbo and supporting mods, I am looking at making... what.. 200-225 ft/lbs at 1600 and 350ish at 2500 rpm. Hopefully at least.

That SHOULD be suitable.

Should. :)
 
Biturbos do not necesarily give more boost, just faster boost. Reduces the lag.

And boy can I appreciate the "no funds for breakage" attitude. Torqu numbers that low should give you all the oomph you need. Only concern I might have would be the front axle universals. If they pop, you could always look into RCV shafts...
 
I, thought, that I had always seen a dual benefit in the twins. You get more boost down low (sooner) so you can have more up high (and later/longer). Though, to be honest, I haven't really looked in to it too deeply.

I am not really worried about breaking things. But if I do.. I do, oh well!

I am just saying that if I roll my Jeep, I'm out some serious money. No two ways about it! Were I to roll my Rhino, I am probably not going to be very inconvenienced. Worst thing that happens is I total the thing and I have to walk home and drive to work tomorrow anyway. ;) I may still be out 7 grand, but I can go to work and such!

I'll absolutely take my Jeeps off road, but it's pretty mild wheeling compared to what most people around here will do. Or at least claim to do. ;)
 
It is always a pleasure to see someone thinking out of the box. The Diesel puts out as much torque as a V8 and sips maybe half the fuel.

I just do not see a downside to this swap...
 
The downside will be the weird maintenance and the efforts required to overcome the swap for the first time. I like to joke (though the story is true). When I did the brakes on my 51 M38 for the first time... the first wheel took me 4 days, the last wheel took me 15 minutes.

From a technical/useability standpoint, there shouldn't be any real downside. That's the goal at any rate.
 
So if this engine "bolts" up to a AX15, would it not then bolt up to an AW4?


I assume because the Jetta is a front wheel drive car, you cannot use the stock tranny, either automatic or manual?





My girlfriend has a 2009 TDI, and I love the engine, and kind of hate the rest of the car. Ive always wanted to steal the engine out of it, this thread just makes me want to do it even more. :nono:
 
He may need to regear the rig. To a lower numerically ratio in order to hold the revs down.

Just asking here, what is the red line on the TDI? 3KRPM?, 4KRPM? Compared to the 5.2KRPM of the 4.0L, I suggest taller gears are in order to take advantage of the low end grunt of the diesel.
 
JeepDreamer: Bellhousing is an AX-15. Just clean.

Starboard: It didn't bolt up. There is an adapter plate. Bellhousing is an AX-15. The AW4 is no good because it's got an integral controller. Yes there are aftermarket controllers.. but at the end of the day.. why do that? It's an automatic and the reality is I am going to spend more time ON road and soft roading where the 5 speed is immeasurably better.

The gear rations are, interestingly, very similar between the stock Jetta and the Cherokee. However the Cherokee rations are actually superior when you put some power into the motor. The only thing that slightly screws up the works is the significantly larger tires. I may have to regear to a 4.10 (or similar).

O-gauge - I think the opposite will happen, as I said above. The Cherokee has much larger tires and a better overdrive. A stock TDI will redline at 4700 rpm, but they are mechanically safe to around 8k. People routinely relimit them to 5500 -6000 rpm. My daily driver TDI routinely is revved out to 5k. In stock form they can't flow enough fuel to get past 47-4800 RPM before they fall on their face. With a tune and injectors it will pull hard into the 5s, but you run out of gearing pretty fast.
 
The AW4 actually could be controlled fairly easily, it's just 3 solenoid wires, a 96 and earlier TCU would not care about the lack of an ECU, except you'd need to mount a TPS somehow... but who wants an auto when you can have a manual?
 
Oh.. sorry Garr:

I think it'll be pretty good. As I mentioned previously. The Cherokee and the Jetta are essentially the same weight. Cherokee gearing is better for a higher power motor and has a better overdrive gearing. Plus I can easily change final drive, tire size and possibly internal gearing (different trans). Anything like that is wildly difficult with the Jetta as it sits.

The only real downside will be on the highway where the Jeep has pretty poor brick-ro-dynamics. No big deal. If I can hit 30 mpg at 70 mph, I will be VERY happy. Anything more will be gravy.
 
Adapter...

Maybe its past my bed time but I would swear that is an adapter between the motor and the front of the bell housing. It looks like a big machined chunk of aluminum about 1 1/2"s thick. Def. not part of the bell.. part of the engine, maybe? You can see it best in the first and 8th pics you posted.But looks like the plate adapter that HPA uses kinda? Not saying your not right but are you sure? Let me know... I'm super curious now. heehee!
 
sweetjeep said:
JeepDreamer: Bellhousing is an AX-15. Just clean.

Starboard: It didn't bolt up. There is an adapter plate. Bellhousing is an AX-15. The AW4 is no good because it's got an integral controller. Yes there are aftermarket controllers.. but at the end of the day.. why do that? It's an automatic and the reality is I am going to spend more time ON road and soft roading where the 5 speed is immeasurably better.

The gear rations are, interestingly, very similar between the stock Jetta and the Cherokee. However the Cherokee rations are actually superior when you put some power into the motor. The only thing that slightly screws up the works is the significantly larger tires. I may have to regear to a 4.10 (or similar).

O-gauge - I think the opposite will happen, as I said above. The Cherokee has much larger tires and a better overdrive. A stock TDI will redline at 4700 rpm, but they are mechanically safe to around 8k. People routinely relimit them to 5500 -6000 rpm. My daily driver TDI routinely is revved out to 5k. In stock form they can't flow enough fuel to get past 47-4800 RPM before they fall on their face. With a tune and injectors it will pull hard into the 5s, but you run out of gearing pretty fast.
Click to expand...

jeepdreamer said:
Maybe its past my bed time but I would swear that is an adapter between the motor and the front of the bell housing. It looks like a big machined chunk of aluminum about 1 1/2"s thick. Def. not part of the bell.. part of the engine, maybe? You can see it best in the first and 8th pics you posted.But looks like the plate adapter that HPA uses kinda? Not saying your not right but are you sure? Let me know... I'm super curious now. heehee!
Click to expand...
I have bolded the important part for you in the above post...
 
Re: Adapter...

jeepdreamer said:
Maybe its past my bed time but I would swear that is an adapter between the motor and the front of the bell housing. It looks like a big machined chunk of aluminum about 1 1/2"s thick. Def. not part of the bell.. part of the engine, maybe? You can see it best in the first and 8th pics you posted.But looks like the plate adapter that HPA uses kinda? Not saying your not right but are you sure? Let me know... I'm super curious now. heehee!
Click to expand...

Yes.. past your bed time. ;) Same idea as HPA, but about 9/10ths the quality, but 1/1000th the price.
 
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