D24 tdi

v8volvo · #1 09-20-2010, 12:37 AM

Have an extra block and head. The block has one cylinder that was pitted deep enough by water sitting in it that it will either need to be sleeved, or bored bigger than the biggest available oversize for a D24/1.6. Wondering what it would take to turn a D24T into a direct-injected engine. I can get TDI pistons to fit no problem. Hard part would be eliminating the prechamber from the head, and finding some way to mount TDI injectors in an IDI head and have the nozzle seat and seal properly and stick out in the right spot.

There will not be any room for glow plugs, but DI engines hardly need them anyway, and with DI just using a grid heater in the intake like a Cummins would work fine anyway.

Would need a different pump to run the higher-pressure TDI injectors, but bet some kind of hybrid could be made using an early Cummins pump. Don't know if the cam would need to change too or not. I think most of the rest of it could stay just the same. Setting injection timing would be a matter of trial and error, but could probably get it to a good place with some experimentation, or find out where the VW M-TDI guys are setting theirs.

Ultimate goal would be to make around a 2.7L, straight six, mechanically-injected, solid-lifter TDI with a VNT turbo... a "D24TDI".

Seems like DI always has the potential for greater power and better efficiency, though I would miss the high-rev powerband and quiet running/refinement of the IDI D24T.

We have a bunch of old 1.6 motors at the shop, including a block and head. Thinking about trying to see what it would take in terms of work on the head, and see if this might be possible.... will put up pictures if something starts to happen.

Jason · #2 09-20-2010, 04:38 AM

It would be cool, but you would have to do extensive welding and machine work to the head. I don't know how strong it would be after that much welding and machining is done. The injector angle and protrusion is very important, besides that the injector itself is shaped totally differently and held into the head in a different way. As for the pump, you can still use the stock ve pump, it generates plenty of pressure to fire those type injectors. The cummins pump has a larger head for more fuel capacity, but the pressure isn't out of this world different. You would probably want to step up to the 12mm cummins size cam plate anyway so you would be able to take advantage of the larger engine. What about wrist pin diameter and pin height betweent the two pistons? They will have to be the same, and I would be concerned about the pin height mostly. As you know deck height has got to be right on and if they are different it wont run.

Jason

v8volvo · #3 09-20-2010, 09:19 AM

The hard part will be getting the injector to mount into the head at the right angle and protrusion, and designing a system to hold the injectors into the head in such a way that proper sealing is achieved against a good surface, sufficient heat transfer from the injector, etc like you say. I don't know if I might be able to use the bottom half of an IDI injector body to somehow screw down on something to hold the TDI injector in, or find a place in the head to tap for bolts with a clamp like a Cummins has.

I have a guy that can make custom pistons for me so if the TDI ones don't fit just right we will be able to sort that out. The head questions are what are going to make or break this idea, though. I want to chop a 1.6 head up so I can see the cross-sections of the prechamber, etc. I think that will give enough info to decide whether it is possible to make it work, or whether it will be too much.

Jason · #4 09-21-2010, 05:48 AM

Quote:

Originally Posted by v8volvo

The hard part will be getting the injector to mount into the head at the right angle and protrusion, and designing a system to hold the injectors into the head in such a way that proper sealing is achieved against a good surface.

AKA, all that welding I was speaking of. You would have to do alot of welding to build up the area enough to start over and machine it to accept the TDI injectors and hold down clamps. It would be a huge project.

Jason

Oddmodman · #5 10-07-2013, 11:51 PM

Any updates? I've been curious about this myself.

745 TurboGreasel · #6 10-08-2013, 02:08 PM

My theory is you are looking at the wrong head.
if you want to take the D24 to the next level, you have to look at it's Audi 5 cyl cousin. The same but shorter. first the turbo'd it, then went to the 20 valve turbo.

Way more top end,crossflow, and a big fat mounting boss in the middle for your injector

jbg · #7 10-09-2013, 05:28 AM

That engine would be a total monster! A D20TiC TDi with a 20-valve cylinder head from an AAN / 7A Audi gasser. Oh man, what a beast!

Oddmodman · #8 10-09-2013, 09:35 AM

And that would work? A gasser head on a diesel? Is it designed to take what that souped up diesel could put out? Because if it did...that would be WICKED!! I like Direct injection, it's more efficient and travels with lower rpms, and a 5 cyl would fit better in my P1800 that a D24T, as was mentioned to me today...

745 TurboGreasel · #9 10-09-2013, 03:05 PM

I want my cake and eat it too, thought more along the lines of cut 2 audi heads and weld them together as a 6 .
Combustion chambers are way too big and will need filled.
Pump will have to move down to clear the intake, but a front timing belt is plenty long. New injector pipes.
they may not be designed for diesel stress, but it's a good motor, and can hold a lot of power.
here is one with 1150 HP. https://www.youtube.com/watch?v=TRpbvpmVfJE