Jump to content
Ultimate Subaru Message Board

Recommended Posts

its possible to do the swap, i talked to my buddy for hours about it, and the hardest thing we came to was the, Jap to German line up with the motor and the tranny/inerds.

 

but if your going to want a diesel and its for 4x4ing have my buddy build you diesel suzuki, great MPG, can fit in tight spots, and over all a solid reliable machine.

 

heres his web page, http://www.acmeadapters.com/index.php

he has his rigs running all over he U.S. great guy too!

 

-Prwa

Link to comment
Share on other sites

 

I don't think converting a gas engine to diesel is practical. GM tried that back in the 80's, and it made for a non dependable engine. Just too much stress with the high compression ratio to get a non diesel designed engine to hold up.

 

There have been many gas engines successfully converted to diesel. But that takes a lot engineering. You can't count the dismal effort that Oldsmobile did in a hurry back in the mid 70s. That wasn't even really a GM effort. It was a home project of two Oldsmobile engineers that got used in a hurry during nationwide fuel shortages.

 

Many HD tractor companies have done it for years. It helps to standardize parts between gas and diesel versions.

 

The Ford 6.9s and 7.3 diesel pickup trucks were built on International Harvester HD gas engine platforms. Same with the 1.8 and 2.2 Isuzu diesels that seem to last forever (I still have two). Nissan and Mitsubishi also did it, as well as many others. I wouldn't be surprised if the first Volkswagen 1.6 diesels were also born from existing gas engines -but that one I'm not sure of.

 

I can't imagine sticking a diesel into a Subaru. Not enough room in front for a inline four. Also the gearing in Subarus is terrible for a diesel engine. Diesels don't make the revs like gas engines and make their best efficiency at 1800-2000 RPMs.

 

Besides that - with diesel fuel costing $4.30 per gallon and gasoline $3.60 - I doubt it would worth having a Subaru diesel if they came here factory built. My 91 diesel Jetta can get around 48 MPG. My 81 diesel Chevette can get 46 MPG. There are newer gas cars of the same size that can run just as cheap when figured at dollars per mile. Years back when diesel was cheaper then gas - it WAS well worth it.

 

By the way, I've got a 95 Geo/Chevy 4WD Tracker with a 1.6 Volkswagen diesel. Gets 35 MPG and is pretty gutless. With the original gas engine it got 28 MPG and was much more fun to drive. But I built it when diesel was much cheaper as compared to gasoline.

Link to comment
Share on other sites

Wish I had a link.

 

In full disclosure I'm a VW guy. I have 7 antique air-cooled's and 3 TDI(Turbo Direct Injection) diesels currently.

 

But way back when VW was thinking of introducing the first New Beetle rumor was it was delayed due to thinking of not making it uness they did a diesel hybrid. One that they already had patented a lot about.

 

Sounded interesting.

 

Apparently most of the patents surrounded this.

 

They basically had one crankshaft for an electric AND diesel engine. Apparently most of the patents were about clutches engaging and disengaging on this crankshaft as one engine took over from the other.

 

At the time the good news was that the New Beetle got such positive feedback at the auto shows they finally decided to make it without this engine.

 

But some searching should turn it up.

Link to comment
Share on other sites

I just have to throw my bit into this-

There are adapters to put a VW TDI onto a Toyota 5speed transmission, the shortcoming would be the rear diff Subaru used. I'm not sure it would handle the torque, but if it would then it'd be like having a mini Mercedes. I would absolutely love to do that on my wagon. Getting the sump around the front subframe would also be a huge challenge though.

I recently wrapped up a swap putting a 7.3IDI into a 69 F250, replacing a built 360 v8. The 360 was a great engine, made decent power, and towed well on the highway, just as I built it to do. Unfortunately it was thirsty. Towing I couldn't expect more than 8mpg, if that. Empty it turned in 12, tops. The 7.3 produces far more torque right off idle, making the truck even easier to drive, and with the help of the five speed I also swapped in it gives mileage in the low 20s in mixed driving. I haven't towed with it yet, but the fact that the mileage is nearly double the old engine with more power is quite promising. I have about $800 into the swap, so even with the more expensive fuel the operating costs have come way down.

Granted, a small car won't have as big of an improvement as a percentage, but still it would be an improvement and even a straight diesel typically gets better mileage than these goofy hybrids.

Link to comment
Share on other sites

I recently wrapped up a swap putting a 7.3IDI into a 69 F250, replacing a built 360 v8. The 360 was a great engine, made decent power, and towed well on the highway, just as I built it to do. Unfortunately it was thirsty. Towing I couldn't expect more than 8mpg, if that. Empty it turned in 12, tops. The 7.3 produces far more torque right off idle, making the truck even easier to drive, and with the help of the five speed I also swapped in it gives mileage in the low 20s in mixed driving.

 

Low 20s in mixed driving? Are you citing US gallons or Canadian gallons? If US gallons, that sound unbelievable to me. I've been driving diesel trucks since they first came out. I've never had a Ford truck with the IDI International Harvester engine break 18 MPG on a long empty highway trip. Granted all my trucks are 4WD, so if your's is 2WD you might do a little better. A typical brand new Ford F250 with a IDI 6.9, manual trans with OD, and 3.50 axles got around 17 MPG on highway runs and 13 MPG mixed driving. 7.3 a hair worse. It's the same engine with slightly bigger pistons.

 

My 1985 Ford F250 with 3.50 ratio axles and C6 trans (no overdrive) and the 6.9 IDI diesel gets a best of 14 MPG empty on the highway and 11 MG mixed driving.

 

My 1994 Ford F250 with 4.10 ratio axles, ED40 overdrive trans, and a turbo IDI 7.3 gets a best of 17 MPG on a long empty highway run. 14 MPG overall average most of the time. Note that when I had the truck in the hills of New York, 15 MPG was the absolute best highway mileage. But when I moved the truck to the flatlands of northern Michigan, it jumped to 17 MPG.

 

My 1991 Dodge with 3.50 axes, 5 speed manual overdrive, and 5.9 turbo-intercooled Cummins DI got a best of 20 MPG before low sulfur diesel. Now it's 19 MPG on a long empty flat highway run.

 

My 1982 Chevy K10 Chevy with 3.08 axles, four speed manual overdrive, and a 6.2 IDI gets a best of 23 MPG, but 20 MPG is more the usual.

 

My 1986 Chevy K5 Blazer with 3.73 axles, 4L60 overdrive auto trans, a turbo IDI 6.2, and a pop-up camper body gets 16 MPG at best.

 

My 1985 Isuzu 4WD mini-truck with 3.73 axles, four speed manual (no OD), and a 2.2 diesel IDI gets a best of 29 MPG but 27 MPG is more the usual.

Link to comment
Share on other sites

but if your going to want a diesel and its for 4x4ing have my buddy build you diesel suzuki, great MPG, can fit in tight spots, and over all a solid reliable machine.

 

heres his web page, http://www.acmeadapters.com/index.php

he has his rigs running all over he U.S. great guy too!

 

-Prwa

 

I've got one with a Volkswagen 1.6 in it. In a 1995 Geo-Chevy-Suzuki-Cami 4WD Tracker. The problem with most Suzukis and all Geo Trackers is gearing. They are NOT geared to take advantage of a diesel that needs low RPMs. With Trackers, there is a rare low RPM differential that was only sold in California versions with automatics. Not easy to find.

 

The Tracker with the 1.6 diesel is underpowered. OK for the woods and fields, but a dog on the road as compared to the orginal gas engine. And if geared down, even worse. Now - if there was some sort of extra OD available, it might work out nicely for flat highway driving.

 

USA "Federal" version Tracker has a 5.12 axle ratio with a five-speed manual trans. With an automatic it has a 4.62 axle ratio. California only had a 4.30 and it's rare.

 

The Volkswagen 1.6 diesel relied on an axle ratio of 3.9 to make it's good mileage. The newer Volkswagen diesels are available with 2.76 axle ratios.

 

The new Volkswagen 2 liter DI turbo engines have some amazing specs. Makes the same max. horsepower and same max. torque at same low RPMs as the older GM 6.2 liter diesels. Same power at 1/3 the size.

 

A GM 6.2 is rated 136 horse/3600 RPM and 240 lbs. torque/2000 RPM.

 

Volks 2 L is rated 140 horse/4000 RPM and 236 lbs. torque/1750 RPM.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...