Saturn TDI Conversion

[Frankencar]

my mk2 TDI only weighs 2107 lbs & it gets 37 - 44 mpg depending on how i drive it (37 towion 2,000 lbs & 44 doing 75mph non - stop for a whole tank) i don't think weight has much to do with milege - you can gat a 2,000lb car rolling almost as easily as a 4,000lb car... i thin that at over 60mph air resistance plays the biggest role in poor milage.

 

[G60ING]

my TDI corrado weighing in at 2860 with me in the car gets 46 mpg beating on it hard but can get close to 60mpg if I really try to drive it easy and leave the a/c off too. This is with a 99.5 ALH mk4 tdi motor and a 3.1 R&P and .68 5th gear. The gearing offsets the smaller tire diameter the corrado has when compared to the Mk4 gears and tires.

 

[RoundHouse]

my mk2 TDI only weighs 2107 lbs & it gets 37 - 44 mpg depending on how i drive it (37 towion 2,000 lbs & 44 doing 75mph non - stop for a whole tank) i don't think weight has much to do with milege - you can gat a 2,000lb car rolling almost as easily as a 4,000lb car... i thin that at over 60mph air resistance plays the biggest role in poor milage.

The weight has everything to do with the mpg in stop and go city driving.



On the interstate the wind drag is a big factor.

 

[CFM]

I haven't run the calculations yet, but my Saturn uses a 195-60 15 tire, which is a little taller than the Jetta's (185-65 14, I think)...should be interesting to find out what the rpm/mph spread works out to be. I keep entertaining the idea of a taller 5th once I get the swap finished, but with the larger tires I probably wouldn't have to use a really tall ratio to get a lower cruising rpm.

I just finished making the axles today; the press fit was a bit of work, but it made for a good tight joint to help keep them concentric when I TIG-welded them together. I spent some time setting them up between centers so I could check them with my dial indicators. I had to tweek them a bit in the press, but I was able to keep the runout to under .002". I was surprised to see more runout on the transaxle end; I always figured VW would be able to maintain higher tolerances than that...guess that's why they run the rubber damper ring on their axles.

 

[Dieseltoys]

Looks great! It's amazing what $200,000 worth of fabrication tools can do huh? I'm only curious why you didnt go with an ALH? Keep up the good work. -Todd

 

[CFM]

I looked into both the ALH and the AHU; I went with the AHU because it's a lot simpler with electronics, has the 3.16 R&P in the trans, and the SMF. Then again, the ALH has a lot of good stuff going for it; I debated the two for a long time while I was researching them, I think it's hard to go wrong with either drivetrain.

 

[alphaseinor]

you can go with a 99.5 or older ALH, that doesn't have any of the immobilizer issues...

 

[Jetter_Sprinta]

I haven't run the calculations yet, but my Saturn uses a 195-60 15 tire, which is a little taller than the Jetta's (185-65 14, I think)...should be interesting to find out what the rpm/mph spread works out to be......

Maybe this will help? And here's the older version of the same page.

Love the project. The fab work is beautiful. Will this be the `08 TDI Fest winner in the "other" category?

 

[vwmikel]

The MK3 doesn't use a 65 series tire. It is either a 185 or a 195/60/14.

 

[CFM]

Thanks for the information! I'll have to give that a whirl and see what I come up with.

Putting the modified Saturn shifter and VW shift cables together, had to make/modify a few things...hoping to install it this weekend, I'll post some pictures of it when I do. Now that classes are over for a few weeks, I hope to make some progress!

 

[CFM]

Haven't had time to update this, but I did make some progress on the car over the last couple of weeks. The A4 shift cables I'm using ended up being a couple inches shorter than what I needed, so that was a minor setback. But I figured out that I can mount them to a bracket under the console instead of at the shifter, so now it's just a matter of making extensions for the cable ends to mate to the shifter. The G60 Corrado intake needed to be notched a bit for the air intake plumbing on the passenger side, so I had to do some cutting/welding to take care of that. I may also have to clock the turbo back a bit, but haven't had a chance to play with the plumbing on that end yet. The wiring harness is nearly done, and I'm making new end tanks for the SAAB intercooler since it was a tight squeeze to get it where I wanted it. I wish it would stop snowing so I wouldn't have to keep digging the car out to wheel it into the garage!

 

[greenskeeper]

The saturn 2 door coupe would definately be a high mpg driver, although even with the 4 door and the plastic panels I think you'll do better than a vw.

 

[CFM]

I thought about that...there is a purple '96 SC2 in the neighborhood that I see on my daily running route, it would make for a really nice TDI swap if I wasn't already attached to my SW2!

The cable extensions worked out to be a simple affair; I machined some Delrin rod to make new bushings for the cable eyelets and sheared some .060 stainless steel to screw to either side. The trick is to form the ends around and create a notch to index into where the eyelets meet the steel rod, preventing them from scissoring during a gear change. I picked up a pair of heim joints for the pivot joint under the shifter...I'll get some pictures of all this posted when my son returns my camera.

 

[lupin..the..3rd]

Wow what an amazing swap! Certainly the first of its kind. I'm subscribed!

 

[VFchicago88]

A great metro swap would be using an XFi... although, that might add a ton of weight, although instant jump from 48hp to 90hp.

And an xfi already gets 50mpg stock.

This saturn idea is cool.

 

[alphaseinor]

A great metro swap would be using an XFi... although, that might add a ton of weight, although instant jump from 48hp to 90hp.

And an xfi already gets 50mpg stock.

This saturn idea is cool.

Imagine what a 3L lupo engine would do...

 

[lost1wing]

At first I thought, what a waste of a TDI engine. But now I'm floored. There is no limit to the talent we find here. My hat is off to you sir.

 

[CFM]

Just a quick shot of the new cable end extentions I made up today, just to give everyone a better visual of what I described. To get the sharp bends, I cut part way through the material thickness, bent it, then TIG-welded some material along the cut. LOTS of filing and hand-fitting the pieces together! I'll post some more pictures later this week as I get the shifter put together in the car. This part of the conversion turned out to be a little more elaborate than I had anticipated/planned, but it's all part of any drivetrain swap.

Thanks for the props, Lost1wing! Even I have to admit that the swap is different from most "normal" conversions, but as you noted, there is a lot of great talent in this forum. I've learned quite a bit from studying other conversions here...always interesting to see what kind of obstacles people run into and how they surmount them.

 

[DaMidget]

My fiancee, who drives a 2000 Saturn SL1, was just joking around saying - "You should put a TDI in my Saturn". I look through here... and someone is doing it... wow

You, sir, are my hero

 

[CFM]

Here's the latest progress pictures, showing the hybrid VW/Saturn axles and after I got them installed in the car. I did have to pop the lower ball joints so I could swing the strut/spindle out a bit for extra installation room, otherwise they bolted right in with no problems or clearance/travel issues. I still need to get some boot clamps for the Saturn boots, though.

The shifter also worked out great; I ended up cutting off the origional cable mount on the Saturn shifter base and making an aluminum mounting plate for the VW cables. It picks up on the two forward shifter mounting studs and another one under the dash so it just bolts right in. The shift throw is very short and has a nice solid feel, about on par with the Berg-5 shifter I have in my '60 Bug. I'm also working on a reverse lockout, but needed to get the shifter installed first so I can locate where the shifter ends up in each gear.

 

[MCR]

Dude. Dude!

 

[abranz]

Utterly amazed, what talent you have. I only wish I had that kind of skill and imagination! Looking forward to seeing your progress.
Tony

 

[KROUT]

You have got some skill. Very nice swap. wow

 

[supton]

I thought my '00 SL woulda made a nice TDI vehicle. Stripper car--only power accessory was the brakes, and I wasn't enamored even with that!--and nice light weight. And a nice large engine compartment too.

Very interesting swap. Good luck on the job!

 

[CFM]

Thanks everyone! It's coming along, although the snow and cold weather has kinda slowed things down. I currently have the shifter all apart on my bench, ended up cutting off the upper end of the shaft and machining a new one out of .625" round stock with a .257" hole bored through the length of it for the reverse lockout pin and cable arrangement. I made it a press/screw-in fit to the pivot ball, TIG welded it together at work, and just finished milling a slot in it for the reverse lockout gate. I'll get more pictures of this posted soon.

 

[fredsTDI]

The shift throw is very short and has a nice solid feel, about on par with the Berg-5 shifter I have in my '60 Bug.

I wish I had a Berg- 5 in my car that would be great but I dont have enough money for that

 

[mr.mindless]

well this is certainly a swap I never thought I'd see (nor a professed love I've ever agreed with, having driven early 90s Saturn SL1s). Looking forward to the end result though, and I must give credit on very nice fab work. Well done so far!

 

[CFM]

Here's the reverse lock-out gate for the shifter. I made it out of some .070" stainless steel and a scrapped fitting that I cut up and TIG welded together. The new shift lever is 5/8" CRS with a slot that I milled and filed for the detent. I just tried it out in the car a few minutes ago, and it works great! Hoping for some decent weather this weekend so I can cast an aluminum shift knob for it.

 

[mr.mindless]

snazzy lockout.

 

[bmwvw]

All I can say is HOLY CRAP!!!!!! this is one sweet swap. Kudos to you and your seemingly boundless imagination. Two thumbs way up!!