TDI Porsche conversion

TDIporsche

Member
Joined
Jan 16, 2010
Location
Knoxville, TN
TDI
924 Turbo
Hello everyone!
So, this is the very eary stages of my idea. I've been quietly reading on here for a while.
I joined this so I can hopefully avoid problems and gain some insight on the best solutions for my application. I have this Porsche 924 Turbo project in my garage, that most of the engine is currently removed. The 924 is a hard one to add horsepower to without extremely expensive mods and the car doesn't get very good gas mileage as is. So, here's the thought - TDI's get 50 mpg's in a 3400 lb. Jetta, my car weighs 2300 lbs.
So, wouldn't I get better gas mileage?
Now some questions: (i am not an expert)
1. The 924 Turbo engine says vw/audi all over it, will I be able to use my current tranny and suspension and/or would I want to?
2. How possible would it be to put an AWD system under it? and which one would give most power/handling, also best mpg? -with power/handling.
3. I'm shooting for 200-250+ HP, without losing the awesome gas mileage. What mods/tuning need to be done to reach these numbers?
4. I gather that I am going to have to rewire my car...?
5. Do I need different gas tank?

At this point in the process I am puting down on paper everything, (or almost everything) I need to get this done. Feel free to leave me info regarding, whatever you think about doing this swap?

Thanks!

I will be keeping a photo journal and tech info updates throughout this process. And, by the way, on my budget this will probably take forever to complete. So be patient with me.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
I'm interested in watching this thread. The biggest challenge will be getting a drive-by-wire car to work in your Porsche. It would be best to find an engine in a whole car (wreck is a good option) that you can use as a donor. At mininum you'll need the engine, engine wiring harness, ECU, accelerator pedal, and some various relays (109, glow plug, etc). You may need the relay panel.

Over 200 HP is a real stretch in these cars, but it can be done. 250 is possible but mostly with 16 valve TDIs only available in Europe.
 

jjordan11

Veteran Member
Joined
Jan 5, 2008
Location
Lehi, UT
TDI
1988 Audi 80 quattro PD130, 1982 Westfalia TDI
I'm not sure if the bolt pattern would be the same, you could do some searching on some porsche forums and see if anybody has done a swap from the original motor to any 4cyl. VW motor such as the 16v, 1.8T, or any others. The bolt pattern would be the same. The gearing would be too low for a tdi too, but with enough research it could be overcome.

I wouldn't do an awd setup on it, I'd keep it rwd with a torque tube going to the rear transaxle. Use a tdi spec fwd trans in the back with the tube attached to it, there would probably have to be a lot of custom fabrication, but it would be a very fun car.

Jon
 

G60ING

Top Post Dawg
Joined
Aug 5, 2001
Location
Alexandria, VA
TDI
No TDIs Currently, I have an R36 Corrado. I've had an ALH Corrado swap, AHU Corrado swap and 2003 TDI Jetta
I am fairly certain that the bolt pattern is different for the Porsche transmission then the standard VW 4 cylinder bolt pattern.

I know of at least one person who has converted his corrado to RWd and he used a Porsche rear end and had to build a custom torque tube with a 02a bell housing to connect it to the transmission. you might want to research what he did in the vorstex's corrado forum's archives. I'd used RWD as the search phrase.

I don't think AWd would be an easy option. If you want to consider this then I would suggest an audi drivetrain but that would probably cause the engine to be shifted forward. You could always use an awd audi transmission with the gears welded up so its a RWD only transmission ;)
 
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TDIporsche

Member
Joined
Jan 16, 2010
Location
Knoxville, TN
TDI
924 Turbo
Hey WOW!
Thanks guys! Yeah, I'm looking for a whole car (salvage/wreck).
I figure I'll need all the parts...
Will keeping the car rear wheel drive lower the gas mileage?
I kinda figured if I can find a 4motion car, I could basically rip out the drive train and suspension, put the porsche wheels back on and fabricate how it connects to my frame?????
Not sure if that would work tho...
The motor in my car doesn't say porsche anywhere on it.
It only says VW/0000. I do know from researching my car that audi and volkswagon developed the car, then didn't want to keep it - so porsche took over.
Things that make you say "hmmmmm"...
 

kafer65

Veteran Member
Joined
Jul 19, 2007
Location
TN
TDI
Early '06 Jetta 5M
One thing to note is that if you're running that much horsepower you're going to have to deal with the massive diesel torque too. I'm handling about 180 to 200 ft/ lbs in my Type1 ok at 1600 Lbs but my old Forester XT had trouble with grip at near 300 ft/lbs with AWD at 3500 lbs. The beetle has a 3.88 diff but the Foresters use something like a 4.48 if I remember right so it got alot to the wheels.
 

DangerBoy

Well-known member
Joined
Jan 16, 2010
Location
Calgary
TDI
2010 BMW X5 35d, 1997 A6 Wagon AEL 2.5L TDI quattro 01E Six Speed Manual (Salvaged 2018)
An Audi 016 you say? This sounds very familiar.

If you do intend on keeping your driveline, I'll be interested in what clutch setup you decide to go with. You and I have the same challenge adapting the engine to that transmission. Maybe if I design and machine a proper adapter plate to my 016 I can build one for you as well. First you have to decide what approach you will be taking.

Dave (The guy with the Audi 5000CD Turbo Quattro TDI swap thread)
 

TDIporsche

Member
Joined
Jan 16, 2010
Location
Knoxville, TN
TDI
924 Turbo
yeah audi 016, good in a way. it would be better if it had LSD.
a couple guys on 924Board were talking about using same tube and everything except the front half, and to use the front half of a 4 cyl vw bellhousing and weld it together.

I am leaning toward the VW TDI. The Audi's are hard to find, and the 2.5 doesnt fit right.
 

Scott_DeWitt

Vendor
Joined
Apr 7, 2004
Location
Texas USA
TDI
2000 Audi A4 1.9TDI quattro
TDIporsche said:
yeah audi 016, good in a way. it would be better if it had LSD.
a couple guys on 924Board were talking about using same tube and everything except the front half, and to use the front half of a 4 cyl vw bellhousing and weld it together.

I am leaning toward the VW TDI. The Audi's are hard to find, and the 2.5 doesnt fit right.
A high torque diesel will shred the 016 internals and the gear ratios absolutely horrible for diesel use.
 
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DangerBoy

Well-known member
Joined
Jan 16, 2010
Location
Calgary
TDI
2010 BMW X5 35d, 1997 A6 Wagon AEL 2.5L TDI quattro 01E Six Speed Manual (Salvaged 2018)
It is nice that the ALH has less torque than the 10V Turbo engine Audi used with the 016, so I would assume the transmission would be fine in this case, but I guess once modified to produce higher HP numbers the torque would have to rise to attain such an increase. I know little but from what I've been hearing from guys who have modded the 10V the transmission is somewhat strong. I always hear people say "it can handle 400 or 450HP", what a misleading statement that is. What would be better to know is what kind of RPM the transmission can handle for input and how much torque it can withstand overall. If you spun the transmission @ 10000 RPM it could very well take 1000 HP, if all the internals could handle the RPM. Then just put on something like 10:1 on the R&P... or do like the first gen Hummer and put gear reducers right on the wheel hubs themselves so the entire driveline can be lighter in weight.

I'm a motorcycle guy and my Superbike puts out 190HP @ 13000 Rpm. It's transmission is very small and light and has no problems. Low torque enough times in a minute will give high horsepower. I know we all knew this, but I just figured I'd rant for a moment about how useless HP numbers are for the strength of driveline parts. F1 cars are light because everything spins so quick. A Ducati has a much bigger transmission than MV Agusta, yet the MV has more HP (typically).

Anyway, good luck with your driveline selection!!
 

Scott_DeWitt

Vendor
Joined
Apr 7, 2004
Location
Texas USA
TDI
2000 Audi A4 1.9TDI quattro
DangerBoy said:
It is nice that the ALH has less torque than the 10V Turbo engine Audi used with the 016, so I would assume the transmission would be fine in this case, but I guess once modified to produce higher HP numbers the torque would have to rise to attain such an increase. I know little but from what I've been hearing from guys who have modded the 10V the transmission is somewhat strong. I always hear people say "it can handle 400 or 450HP", what a misleading statement that is. What would be better to know is what kind of RPM the transmission can handle for input and how much torque it can withstand overall. If you spun the transmission @ 10000 RPM it could very well take 1000 HP, if all the internals could handle the RPM. Then just put on something like 10:1 on the R&P... or do like the first gen Hummer and put gear reducers right on the wheel hubs themselves so the entire driveline can be lighter in weight.

I'm a motorcycle guy and my Superbike puts out 190HP @ 13000 Rpm. It's transmission is very small and light and has no problems. Low torque enough times in a minute will give high horsepower. I know we all knew this, but I just figured I'd rant for a moment about how useless HP numbers are for the strength of driveline parts. F1 cars are light because everything spins so quick. A Ducati has a much bigger transmission than MV Agusta, yet the MV has more HP (typically).

Anyway, good luck with your driveline selection!!
In stock form the 016 will push the rear support bearing through the center section @ 300 ft/lbs of torque. The 5th gear will strip shortly thereafter. Many people with high horsepower 5 cylinders (500+) can shred teeth on gears 1-3 with a full throttle launch.

People who say these gearboxes can handle 450 horsepower are mis-informed.

The 951 944 turbo is the strongest FWD 016 available however I don't recall if this Porsche is a 924 or a 944..

If you keep the tdi at stock power levels you will be fine (although the ratios suck horribly for diesel use).

It's not horsepower that kills gearboxes, it's torque.
 

kafer65

Veteran Member
Joined
Jul 19, 2007
Location
TN
TDI
Early '06 Jetta 5M
Scott is right on the money. I think its going to be a cool conversion--no doubt! I'm just saying with a high output turbo diesel, especially with a VNT type turbo , you're getting very early spoolup in an engine that's a tsunami of torque well before 2k rpm. There's some strong forces transfering to the tranny and mounts.
Traditionally, something like mid to high 2:1 ratios are used for differentials to help tame the immediacy of the torque. It will be hard not to want to tug on that torque all the time. I think my 83 300td had a 2.73 rearend with 57hp if I remember right.
A lighter car may give you better city mileage. Aerodynamic drag will be a bigger player at highway speeds. Older cars tend to be lighter and the wiring a little simpler so I like the old iron better, but thats just me. I'd love to do a convertion myself, but I'll have to live vicariously though the forum for now.
 
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Scott_DeWitt

Vendor
Joined
Apr 7, 2004
Location
Texas USA
TDI
2000 Audi A4 1.9TDI quattro
You can find a early diesel 5 speed from a audi 5000 diesel.. These are very rare, and I'm not even sure that those parts will fit into your transmission (not all 016's are the same).

So in reality there is little you can do to improve ratios. However I wouldn't let that be a deterrent.
 

Scott_DeWitt

Vendor
Joined
Apr 7, 2004
Location
Texas USA
TDI
2000 Audi A4 1.9TDI quattro
TDIporsche said:
alright, i know where on is.
how do i find out if they fit????
You are going to have to use the Porsche case and I'd recommend the Porsche final drive. If my memory serves, you also want to use the Porsche 1-2 gears and main shaft and 3,4,5 from the Audi diesel.

To see if the parts will interchange you will have to take apart both gearboxes and do the leg work. It's probably a good time to replace the syncros and seals while your in there.
 

TDIporsche

Member
Joined
Jan 16, 2010
Location
Knoxville, TN
TDI
924 Turbo
alright.
i need to know how to translate diesel torque from gasser torque in relation to horsepower.
here's the deal. i'm gonna be using a 4cyl 1.9 TDI engine, (more than likely) from what i've read it's pretty easy to get between 150 and 200HP with a few mods. if i am brining 150 - 175 HP, i'll be trilled! not tryin to break salt-flat records or take it to the track. i've got a very nice handling car that was pretty quick at 150HP with it's own motor in it.
i want a quick, fast, nimble car that gets 50+ mpg's!
the way the 1.9 TDI makes a jetta get up and jump, (the jetta weighs almost 1000lbs. more than my car) - it should make my car scream with acceleration! ya know?
 

apavlov13

Member
Joined
Jan 24, 2010
Location
New Paltz, NY
TDI
AAZ mk2
I know most 944's came with a very tall 5th gear. Gears 1-4 are closely spaced within reason, and then 5th is almost like an overdrive gear.

I would look into getting one of those gearboxes if your 924 doesn't already have one. It shouldn't be too hard to find since a lot of 944 guys are getting rid of these boxes in favor of a close ratio one for the track.

Then again you could always stick with what you have and worry about actually getting the motor in. Then if it turns out the gearing really does suck, you could get a different transmission or spend the big $$$ on building one.
 

Pat Dolan

Veteran Member
Joined
Apr 19, 2002
Location
Martensville, SK
TDI
2003 A4 Variant, 2015 Q7
This is a swap that I have been waiting a fair while to do. Except, I will use the Audi 2.0 5 cyl engine - since it bolts right up. I have seen this engine installed in a 924 (I think the thread was on this site), but the valve cover/inlet is a little high to clear the 924/44 hood. The simple solution is to cut the torque tube and twist it to lower the engine a bit (or blister the hood).

Should qualify this for you. The engine SAYS VW/Audi all over things, but the 924 is based on the Audi 100LS - which was designed BEFORE VW bought the company. In fact, the Audi Fox is what set the new family of VW engines (along with a different bolt pattern). All Audi stuff from that era has the bolt pattern of the 90/100/100LS, so thus does the 924/944/968. While the 2.0 is still available (cheap, a few around - and if you find one from a C1 car, you have also found your gearbox - C2s were all automatic in North America) the better bet is a 2.4 - which was sold in Canada for Eurovans and most were service vehicles in ON and QC that are all rusted away. These are, of course IDI engines. The 2.5 TDI is a bit spendy (see Scott deWitt if you want one).

If you want to go with the four banger, if the 5 cyl won't fit under the hood, it won't either. So, you need to change its angle, and you need a bellhousing. To do that, I would suggest getting a Vanagon TD opr one of the aftermarket convestion bell (actually, whole rear of the trans) meant to install inlines in T3s. Weld up a new torque tube to bolt to the gearbox split pattern (lenghts will change, but the driveshaft splines should still end up in the right place - bearing location migh move though) and you have a factory bell housing....but big problem with that one is the starter may not fit up the tunnel (is on the wrong side in the Vanagon installation). Rotation MIGHT solve that.

You can see why the 5 cyl makes so much more sense.
 

i<3TDIs04

Member
Joined
Nov 25, 2009
Location
Miami
TDI
91 jetta w/ 2000 tdi, '09 jetta TDI
3. I'm shooting for 200-250+ HP, without losing the awesome gas mileage. What mods/tuning need to be done to reach these numbers?
.[/quote]

diesels dont lose mileage when u modify them.
 

Pat Dolan

Veteran Member
Joined
Apr 19, 2002
Location
Martensville, SK
TDI
2003 A4 Variant, 2015 Q7
i<3TDIs04 said:
3. I'm shooting for 200-250+ HP, without losing the awesome gas mileage. What mods/tuning need to be done to reach these numbers?
.
diesels dont lose mileage when u modify them.[/quote]The way you do this with ANY diesel is calculate how much fuel you need to the get power you want and put that much pump and injector nozzle in place. Then you need to control the pump for the deliver and timing you need (modified mechanical pump or electronic programming for those engines) and the rest is all about managing airflow with bigger turbo, exhaust, porting, intakes, etc. to get enough air to BURN all of that fuel.

You are right in that diesels don't tend to lose much or even gain some efficiency with mods, but if you use that double or trippled fuel delivery, you will sure as heck get poor mileage.
 

G60ING

Top Post Dawg
Joined
Aug 5, 2001
Location
Alexandria, VA
TDI
No TDIs Currently, I have an R36 Corrado. I've had an ALH Corrado swap, AHU Corrado swap and 2003 TDI Jetta
VW has had the same bolt pattern for USA spec watercooler 4 cylinders since 1974 to current.

The reason why I say usa spec is because there are some oddball watercooled VWs in europe that this doesn't apply to.
 

G60ING

Top Post Dawg
Joined
Aug 5, 2001
Location
Alexandria, VA
TDI
No TDIs Currently, I have an R36 Corrado. I've had an ALH Corrado swap, AHU Corrado swap and 2003 TDI Jetta
All 4 USA spec FWD watercooled cylinders are the same bolt pattern (gassers and diesels)

the VR6 uses a different bolt pattern but this VR6 pattern is the same as the 5 cyclinder bolt pattern.

The Audi transmissions like that used in the A5 (b5 platform) have multipattern bell housings and then they use spacers if necessary. For instance a VR6 (yes VR6 not v6) can be bolted to and Audi A4 transmission with a factory spacer.
 

Scott_DeWitt

Vendor
Joined
Apr 7, 2004
Location
Texas USA
TDI
2000 Audi A4 1.9TDI quattro
G60ING said:
The Audi transmissions like that used in the A5 (b5 platform) have multipattern bell housings and then they use spacers if necessary. For instance a VR6 (yes VR6 not v6) can be bolted to and Audi A4 transmission with a factory spacer.
The VR6 does not share the exact same bolt pattern as the 5 cylinder if you consider the orientation of the engine, however a factory adapter is available (which I sell) That adapts the VR6 to a V6 bolt pattern which will bolt up to any of the B5 gearboxes. The twin turbo engines use a spacer between the engine and gearbox, however the 2.8V6 does not, but the 2.7 and 2.8 share the same bolt pattern.
 

manual_tranny

Smyth Performance- Intern
Joined
Jan 5, 2010
Location
New Bedford, MA
TDI
2001 Golf @182K; 2000 Jetta @290K
I agree with you, it will be a quick car if you get the right gearing. 924 handling is dynomite too. I have an ALH motor in my Golf now, but my first car was an old beater 1978 924. I hate that Audi motor with all my heart. I wish you the best of luck though, I hope it is worth saving the 924. It would be my guess that installing AWD from any other car would be bloody nightmare. Spend your money on a good clutch, a good differential, and nice tires. You will need them when you realize that what your 924 has been lacking all this time is not power, but torque. Speaking of torque, have you ever driven a 944? Or a 968? Or a 928?

No offense, but I think you should drive a 944 (NA or turbo) or a 968 before you endevour into this engine swap. The 968 would probably run you a lot less than this conversion, and you could save your money for gasoline. (I know you want better economy, but I'm playing devil's advocate here). There are several 968s on ebay right now. I once drove a 944 (normally aspirated) and I promise you the grin it put on my face was very wide.

http://motors.shop.ebay.com/i.html?_nkw=968&_sacat=6001&_trksid=m270&_dmpt=US_Cars_Trucks&_odkw=&_osacat=6001

Did you know it has one of the LARGEST 4cyl production engines ever? 3 Liters. You wouldn't believe what that feels like. (Ever drive a truck with a 7-8 liter V8?)
 
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