13 replies to this topic

[Brackets]

This may very well be one of the dumbest questions in techforum history ;)...

Yesterday I passed a VanHool bus, and it had a big banner on the side stating: "First VanHool bus fitted with Detroit Diesel Engine".

What is that? Is 'Detroit Diesel' a company or a technology?

[carlos.maza]

Detroit Diesel is a North American Company. As far as I know, it belongs to the General Motors group.
It makes two-stroke diesel engines

[EddieJF1]

http://www.detroitdiesel.com/

A DaimlerChrysler Company.

[Ali_G]

2 Stroke diesel engines.

Kinda unusual in a truck isn't it.

Niall

[Timm]

Until fairly recently, Detroit Diesel was part of Roger Penske's empire. Apparently, under his control, it became quite a healthy organisation.

Don't mock 2-stroke diesels, they're very efficient

[bugeye]

2 Stroke diesel engines.
Kinda unusual in a truck isn't it.
Niall

Actually, not at all in the US anyway, the GM 6v Turbocharged (and supercharged of course) 2 stroke diesel has been the motor of choice in the bus/marine industry for quite some time. Extremely Reliable, Compact and Powerfull. I drove a 40foot transit bus for some time with one of these units. Reasonable speed (for a bus) and unbelievable feul economy. (IF I remember correcty it was better than 12miles per Gal(US) around town fully loaded with standing room only. This was about on par with a big block station wagon of the era with a couple of folks in it...

And If I remember my history(channel) GM Deisels powered the landing craft to Normandy among other things.

Emmissions concerns are (I Think) causing the old 53, 71 and 92's to go the way of the dinosaur. If I remember correctly, the "92" in 6-92 is the Cubic inch displacement of one cylinder.

[carlos.maza]

EddieJF1:

Thanks for the correction. A Daimler Chrysler Company....

[BRG]

Detroit Diesel has appeared as a sponsor on some CART cars in the past IIRC. But I don't remember which team or driver - was it Al Unser Jr maybe?

[Timm]

When Detroit Diesel was part of the Penske Group (ref. my post above), the name appeard on the rear wing endplates of their Champ Cars

[marion5drsn]

Go to www.detroitdiesel.com
M.L. Anderson

[Engineguy]

Originally posted by carlos.maza
Detroit Diesel is a North American Company. As far as I know, it belongs to the General Motors group.
It makes two-stroke diesel engines

Almost all of Detroit Diesel's current production is now four-stroke. Most of the remaining two-stroke production is for existing military contracts, and they are trying to transition those to four-stroke also. They are heavily into production of engines for cars, minivans, and SUVs now too.

When Penske took over from General Motors in 1988, DD was dying, and had about 4% share of the markets they were in... now it's something like 30%. Roger Penske is still Chairman at DDC and they seem to be quite independent from DaimlerChrysler for now, nothing like the Chrysler debacle. DaimlerChrysler only purchases about one third of DDC's output. I've seen DaimlerChrysler referred to as DDCs "indirect parent company" whatever that means... not sure of the exact business structure.

[Ray Bell]

Originally posted by Ali_G
2 Stroke diesel engines.

Kinda unusual in a truck isn't it.

Niall

Actually, Ali, these are not two strokes in the traditional mode. They don't rely on crankcase compression to fill the cylinders via ports, but they are filled via an inlet valve in the head.

This means, of course, that they must be supercharged, and this is why the preponderance of GM blowers on the dragsters over many years... they were just so available.

Today they are usually, IIUIC, turbocharged as well as supercharged, so the air is pumped in the top, the ports at the bottom of the cylinder are exposed by the piston reaching BDC and the exhaust is hurried out there by the incoming charge.

Naturally, the mandatory use of fuel injection in a diesel ensures there's little fuel loss... or none if it's running at 12mpg...

And indeed, the 71, 92 etc is the cylinder capacity in cubic inches, so a 6/71 is a V6 with 71cid cylinders, giving a total capacity of 426 cubic inches, or 7 litres (near enough). They come in a variety of configurations, but mostly V6 and V8. Two V8s can be tied together to form a V16, and this is not uncommon.

Of interest is the fact that the pre-war Auto Union Grand Prix cars used the same 2-stroke technology... overhead cams and inlet valves, piston-cleared exhaust ports, lotsa noise...

I imagine the swing to 4-stroke is for cleaner emissions...

[XHawkeye]

One very minor quibble 6-71 was inline, if it's a V its 6V-71 or 16V-92, etc. A very dependable motor, since they were 2 strokes they sound great for a big diesel motor.

The switch to 4 stroke almost killed Detroit and GM basically gave it to Penske for half a song. Who was able to work the bugs out of the 60 series motor.

Now if we could just get the big shots at HQ to sell the rest of GM to Penske.

[Melbourne Park]

DD were also popular in Australia, I don't know now though.

There's a Sarich designed two stroke engine which is making it,slowly, into production (I know the designer). It blows air across a stream of fuel into the cylinder, the atomisation is good and the process is very cheap. Mercury now use this system. Deisel was also viable, but I don't know if the cost savings were worthwhile in a diesel, probably not ...