Attention Diesel Fanatics

[seattle smitty]

Mr. McDonald,

I saw that you were guaging interest here in diesel topics, and would like to put in my two cents. I observed to Mr. Vizard some time ago that some people here, and a lot of old racers and rodders elsewhere, are increasingly interested in rebuilding street engines for increased efficiency, meaning better throttle response and low-to-midrange power when needed, and better fuel economy all the time. My suggestion was that the GFN crew consider opening a separate "Fuel Efficiency" forum, since the topic is getting some attention already. A lot of us don't need or want 500hp for the street. What we want is ways to cut our consumption of $100/barrel petroleum.

This particularly applies to operators of big commercial vehicles. My mobile-welding service truck has a Ford 460 engine, which I will shortly rebuild with tight-squish closed-chamber 429 heads, better exhaust system, better carb and manifold, and all the standard tricks for improving efficiency (it will make a lot more power, too, but that isn't particularly important). A lot of my customers run diesel trucks and diesel equipment, and burn hundreds of gallons a week, and the cost of fuel is a huge issue with them. Many of them are mechanically skilled enough to rebuild and modify their equipment, and any pointers you can provide that will cut their fuel burn would be most welcome.

Personally, I will shortly be working on a couple of small diesels for daily-drivers, a Toyota 1C-T in an '85 Camry, and a Nissan SD-22 for my little pickup.

What I'm getting at is that maybe not all of your readers here will be building mega-horsepower off-road monster trucks, while still being very interested in upgrading their diesel engines. (I hope the monster-truckers don't leave tire tracks all over this suggestion
Wink )

[Robert_McDonald]

Is there any way that I can take a look at one of these heads? I would be interested to find out how they perform on the flow bench and what swirl they produce! If you would like, drop me a post if you are interested and I would be glad to do some tests on it.

[Robert_McDonald]

In reply to seattle smitty and the TDI Meister, I understand where you are coming from and where you are going. You are correct, we are in the early stages of refining some small diesel engines. The one thing that people often overlook about diesel engines is that they are crude machines. There is plenty of power to be gained just by paying attention. I see these articles of the bio-diesel and the vegetable oil all the time, and lets throw some bolt-ons in there too. A diesel has much to be improved upon and I will be glad to point out some of these very soon. As for you TDI-Miester, can you send me a cylinder head for review. If so ,reply and I can do some flow, swirl, and sonic testing to see what kind of improvements can be made.

[Brian P]

The Volkswagen 1.9 TDI rotary-pump engine has a fair amount of stuff available for it, if you know where to look. In USA, these were sold 1996 through 2003 without major changes. Try Fred's TDI Page. TDIClub.com. VW TDI Enthusiast Community for the goods on that one.

The successor to that was the "pumpe-duse" (unit-injector) 1.9, of which I have one example. Mine is chipped. Works well enough for what I do with it. The version here in North America is still a 2-valve-per-cylinder design, but the fuel injection system is different.

The real trickery will be with the 2009 engine. Common-rail injection, 4 valve DOHC head, 16.5:1 compression, and a TON of emission control stuff.

Agreed that there's a fair bit of room to improve the TDI engines. The intake port is typical production-engine rough cast. The exhaust ports in the head don't even come close to matching the holes in the manifold. The camshaft is incredibly conservative. The turbo is pretty small (and pretty weak) in the interest of low-RPM takeoff from a standstill. Neither the intake nor exhaust manifolds are particularly stellar design examples ... they're designed to be cheap and to get the job done. When starting with the deliberately de-tuned lower-powered models, it's almost a no-brainer to bump power output by 50% and some people have doubled it. Beyond that it starts getting tough (and you'll be well into needing stronger driveline parts anyway). The factory made as much as 150 hp from a 1.9 P-D and 170 hp from a 2.0 (four valve per cyl) P-D. A pretty good starting point is to just copy what the factory did on those ...

Here is a TDI performance bits supplier to check out: KERMATDI Home Page

[Blownoiler]

I would like to see articles on the older "indirect injection" diesels....the 2.2 Isuzus, 2.4 toyotas etc. Dont laugh.... I'm serious, these older engines are built to take anything so there are still plenty of them around and they are SLOW!!....Every owner of a Toyota 2.4 N.A. or turbo diesel spends too much time searching the bowels of the internet for horsepower mods, the problem is all the performance sites are for the big engines/trucks. With diesels becoming more and more popular the first sites who cater to the small oilers will have a larger following 2 or 3 years down the track. I just bought a small rootes blower for my 2.4, along with a large intercooler, lightened flywheel etc. I have no idea if these mods will give me the results that I am expecting. Has anyone ever played around with one of these engines?

[MilesTugoh]

I am in agreement with seattle smitty, TDIMeister, Brian P, and Blownoiler. The small diesels, and their enthusiast owners, deserve forum space to exchange info and experience on the refinement of these engines

My Isuzu Pup diesel is still in great condition and used regularly. Improved torque and better mileage through refinement couldn't hurt ..