Wacky, but bear with me....gasoline to diesel

[bryson]

Would this work?

Idea: Find an aluminum V8, like maybe the Ford DOHC (might not work, just an example). Make sure you start with a decently strong block, then beef it up more by adding a main girdle and filling the block if it needs it. Add a stroked crank -- it would raise the compression enough for a diesel, and you could use a shorter rod to help with low RPM power. If there is enough room in the combustion chamber (choose the engine wisely), you retap the spark plug threads for a diesel injector, and add a glow plug -- that would probably have to be drilled and tapped by a machine shop. You would have to take a lot of parts from an existing diesel car, like the ECU, injectors, glow plugs, fuel pump(s), and possibly a few other things. I would turbocharge the engine also, and probably run an engine brake.

I probably wont ever do this, I just like to roll it around in my head. Any reasons why this wouldn't work?

[crzyone]

Any reasons why this wouldn't work?

Why would you want it to?

[teamlseep13]

It is certianly do able with enough money and time.
I have a much simpler soultion though.

Buy a crate diesel engine.

All your engineering and work would be done for you, you would have more aftermarket support if you used a popular model and it would cost MUCH MUCH LESS.

Start lookin on ebay.

[Kohburn]

no reason you can't convert a gasoline engine to diesel..
but yeah - whats the motivation behind all that work rather than finding a diesel engine that already fits the bill.

[p8ntman442]

how do you plan on driving the injector pump?

[Kohburn]

how do you plan on driving the injector pump?

it'd probably have to be belt driven - but those bastards are massive since they have to get the fuel to 1200-3000+psi

[Pyrthian]

of course it possible. but, it would be a terrible waste of time & money. would be cheaper to just buy a fine German diesel. just like everything else - its always better to buy the whole package, than pieces at a time. but, if you are just doing it to do it, for learning, for whatever, of course its possible. this last generation of diesels are SOOOO much better than the diesels of 5-10 years ago. much has gone into them, which I am sure is not reproducable in someones basement/garage.
best I'd expect is the classic noisy, stinky diesel from a homebrew.
so quite you can hear a piano drop....

[Mach10]

Wouldn't you want a LONGER rod for better low end power? (more dwell, more leverage)

In any case, you'd also have to machine the heads to accept direct injectors... And the airpath through the gas heads might not be so optimised for diesel (not enough tumble in the chamber?).

Buy the crate one.

GM's diesels were "converted" gas blocks. And they sucked ass. You can find a few with hundreds of thousands of miles on 'em... But the vast majority tore themselves apart.

[The Dark Side of Will]

The 4.3 diesel had a different block casting than the gasoline engine, or so I have been told. I saw one in a junk yard once. I should have paid the $150 or whatever for it just for the sake of novelty. It had injectors in the spark plug holes. I don't know if it had glow plugs or not.

The CAT 3115 in the truck at my old job didn't have glow plugs. It had an intake heater instead. As long as you let the intake heater run until it shut itself off, it was pretty easy to start, although I don't think it ever got much below freezing.

[TurboGT]

You would have to do some crazy work to the heads for the injectors.

[bryson]

Wouldn't you want a LONGER rod for better low end power? (more dwell, more leverage)

A shorter rod will accelerate the piston away from TDC faster, helping the air get moving at low RPM when it doesn't have much momentum built up. I think matching the cam profile to the rod/stroke ratio is more important than the length of the rod itself, but rod length is a whole different game.


Does anyone make a production aluminum block turbodiesel, V8 or otherwise?

[Kohburn]

the question is.. can you do the same thing as a diesel, with gasoline..

there is no need for a spark plug or any worry of preignition since the fuel is injected at DTC and the heat of the air at the high pressures is what ignites it..

and would a faster burning fuel source such as this enable a diesel style of engine to be able to hit higher rpm? or would the forced involved shatter the damn thing

[TurboGT]

You could run gas in a diesel if you found some different injecotrs. Gas dosnt have enough luberacant and would seize the injectors.

[Kohburn]

You could run gas in a diesel if you found some different injecotrs. Gas dosnt have enough luberacant and would seize the injectors.

good point - would require a redesign or some addative

[The Dark Side of Will]

Diesels are built the way they are because they have to deal with constant detonation. If you built an engine to run gasoline in the diesel cycle, it would have to be built like a diesel.

Injection timing in a diesel is like ignition timing in a gasoline engine, AIUI.

Audi's R10 is probably an aluminum block engine. Not sure if VW's V10 TDI in the Touareg is aluminum or iron block.

[Mach10]

The 4.3 diesel had a different block casting than the gasoline engine, or so I have been told. I saw one in a junk yard once. I should have paid the $150 or whatever for it just for the sake of novelty. It had injectors in the spark plug holes. I don't know if it had glow plugs or not.

The CAT 3115 in the truck at my old job didn't have glow plugs. It had an intake heater instead. As long as you let the intake heater run until it shut itself off, it was pretty easy to start, although I don't think it ever got much below freezing.

I was talking about that 6.0/6.5 diesel they were using until a few years back...

I was told the casting was the same, but in 4-bolt flavor. They broke a lot