90turbo1

Except for the fact that the pump in the tank is a transfer pump only, and the fuel pump for the engine is engine driven. and goes directly to the injectors. but shouldnt be to hard to make work anyway.

isuzu made some silky smooth diesels in the early 80 for the Pup truck and the dodge (imported small truck) they sound like little cummins engines and most didnt have a turbo but thats a minor obsticle with a diesel.

sub9lulu

iTrader: (7)

do it do it
imagine ... 400hp and 700lbs TORQUE @ 1000rpm !!

aa35199

iTrader: (1)

very interesting stuff, I say go for it, then mod the motor so your 7 is faster then it was befrore. One of my VW buddies told me about some poeple on VW vortex getting insane amounts of power out of their TDI's (500+ fwtq). I also saw an episode of top gear where they took an old vw golf (mid 90's) intalled a simple wet nitrous kit and managed to beat honda NSX in a quarter mile drag race. Deisels have great potential, why not?

rotarygod

iTrader: (1)

I love diesel engines. I just don't have one (yet). The next car I buy will be a diesel. A VW 4 cylinder TDI engine would be a nice conversion. It shouldn't be hard to get a 1.9L up over 150 hp or more. That may not sound like much but remember that it's about the same amount of horsepower as a stock n/a 2nd gen but with TONS more torque. That would be faster and you'd probably get gas mileage in the 40's. Not a rocket but faster than stock. That sounds good to me. The VW diesels redline at 6K too although there is no point in going nearly that high. Since they use really high fuel pressures you'll need to also use their ecu and fuel pump setup. Time to look for a diesel Jetta or Beetle in a junkyard and take what you want. Fabbing everything up really isn't that hard like many make it out to be. If a person didn't have some ability to do this or get it done, they probably also aren't thinking of doing a conversion either. I'd love to see it done. I'd actually love to see a true compression ignition rotary engine though. There is only one that I know of and it's a small 1 rotor that is about 15 hp used as an auxiliary power unit for business jets. I want to see pictures if a diesel (whichever one it may be) is thrown in an RX-7. I'm more excited about this idea than I am of V8 conversions. V8's have never done anything for me. Not knocking them. They just aren't my cup of tea.

josh...just josh

diesel rotaries dont really make a lot of sense to me. Diesel only burns so fast (hence one of the major limitations for how fast a diesel can spin) and since the close proximity of the combustion event to the e-shaft in a rotary doesn't offer much mechanical advantage, you cant fully take advantage of what really makes power in a diesel, extreme pressure and force. I have thought about this a lot, you see the guys that are making ridiculous torque with the 1.9TDI's. I would love to see what a built, twin turbo TDI would do in a great chassis (ie RX FWD heavy VW's aren't really performance to me..). there would be nothing like coming out of a corner with 300 ft/lb at 2k!

andy 123

ericgrau

iTrader: (1)

There are other similar looking cars you can do this to.

Unlike previous rotary powered cars, the RX-7 is built around the rotary engine to insure an even weight distribution for nice handling. Diesel piston engines have even more pounds per horsepower than a regular piston engine. Yeah you can tune them and what not, but rotaries (and I assume petrol pistons) are just as tuneable. I could see this idea working with maybe a 1.5L-1.8L diesel (or any engine that's close to the weight of the original engine and located about as far back). It'd be pretty slow, but the fuel economy and handling would be nice. Yeah, you can put a heavier engine in there and it will handle okay, but then you might as well get any car from the same era and drop the diesel in that car instead.

As for torque, the fact is all cars are equipped with magical things called gears that convert rpms into torque and vice versa. i.e., until they make a diesel with a 7000rpm redline those torque numbers don't mean jack squat. Those same gears that you're looking at to double the rpm output (compared to a non-diesel) also cut the torque in half. Fortunately the industry gets around this by rating a car's power based on the product of torque (Nm^2) and angular shaft speed (rpms/(60s/min) * 2 * pi). This product remains the same at the wheels (minus drivetrain losses), regardless of gearing. This product is in Nm^2/s, which is kW. Man I love the metric system, it makes this so much easier.

fromtib27

iTrader: (2)

I'd like to get this thread going again. I'm debating on swapping the 4bt cummins engine in a FD. Maybe I can get some tips or ideas from some members on here with more knowledge on deisels and engine swaps then I have.

capn

Well I don't know why you'd want to put an engine in that weighs 3 times more, and puts out less than a stock 13B.

I'm not too familiar with the 4BT, but the engine is going to have a very low rev limit like 3500rpm or something. And with the RX-7s short gearing you will be very speed limited.

gnx7

iTrader: (10)

Measure a Cummins engine. They are crazy tall. No way will any cummins motor fit into an RX-7 without it getting a lift kit.

6BT weighs about 1,000lbs
4BT weighs around 700lbs

The engine that makes the most sense is a VW 1.9 TDI motor with an adapter plate to mate up to a Mazda transmission.

turbotim

I just finished my 2jz swap into my fc, but I was already thinking of the next one and going diesel, you guys are thinking small, I am gona get the v8 swap kit from granny speed shop and shoe horn a duramax in the engine dimensions are simular to a big block v8, the engine may be a little taller but I will deal with that when I get there.

I like the idea of haveing a 10 second car that gets 40 plus mpg. ya the engine weighs 835 but I am sure I can beef up the front springs a bit.

chiptuner, exhaust and intake is all you would need to make it move.

this is just an idea I have and I will research it heavily next fall for a winter project. I will probly buy a written off 2wd duramax truck and swap it all over.

MK3Brent

iTrader: (6)

Do something, post some pictures or something.

12arotary.

you are going to love it till you make a turn haha there is a good reason people keep mentioning the TDI- half your cars weight in one spot isn't the best idea. If you really want something with a duramax you need either mid engine or build the car yourself because i don't see how you can get alway with that much weight in front and still make it drivable

gnx7

iTrader: (10)

How about a mid engine Duramax with a Ricardo (Ford GT) transaxle? Then the weight is nice and centered....

I doubt a Duramax will get 40mpg... when a Jetta TDI engine is 1/4 the size and gets 45mpg to low 50's mpg highway with a manual transmission. The automatics only get low to mid 40's average.

12arotary.

I'd say it would be 40 easy in a car less than 2500lbs- that is the glorious thing about direct injection and computer controlled injectors you only have to inject the fuel you need (Which on a diesel is very little)- Diesel actually does better in high volumes of air and can run very lean when little power is needed- I'm pretty sure whether a TDI 1.9 or a duramax 6.6 were placed into identical cars (parts removed when the duramax is in to make them both weigh the same) It would get almost identical fuel economy except with the duramax you would have tons of power when you need it.

Brian Conran

I have an '09 Jetta TDI wagon which is my other car. It accelerates like a freight train, and is actually a blast to drive at 80 miles an hour on the freeway. The worst mileage I have ever gotten was 31 mpg. It's quiet because VW engineered it from the cylinders on out to the end of the exhause to be extremely quiet, although the cars used in the Jetta TDI cup racing series run without a muffler and are still very quiet. As for converting a rotary engine to diesel fuel, I think the biggest technical challenge would be reaching the proper compression ratio (low to mid 20's as I remember). I asked one of VW's crew chiefs at the TDI Cup in Joliet Illinois two years ago, and he wasn't sure it could be done due to the issues of compression and apical seals.