95 mk3 vr6 -> turbo diesel

[gigaz2]

and what about pumping losses? the IDI has a LOT of them because of the high CR, lowering th CR would reduce them.

in my view, I would: reduce CR, decrease injection time(bigger pump head/camdisk?), improve spray (4 or 8º injectors).
the camshaft also plays a very important role on the sfc curve, but on a diesel there isn't much that can be done.

a turbo doesn't make a difference on the sfc, but it enables us to use a lower RPM that wasn't usable on NA mode.

[gigaz2]

ok that makes sense, and goes in the same line of thought I was having in the local café: the pumping losses we can control are due to the restrictions on the intake and exhaust, so the 1.9 head on 1.6 bottom end should need slightly less fuel for the same power output right?
it would take less power to suck in the same amount of air.

[kane66]

THANK YOU jtanguay..... that is exactly what I was looking for. I had the information for were it was the most efficient but not were it is least efficient. It's interesting to see that the curve is so shallow between 1000 to 3000 rpms. I did the math based on worst(280 g/kwh)/best(264 g/kwh) case scenarios over the 1000-3000 rpm power band and found there is only a 6% difference in fuel consumption in that power band..... very interesting... So really, unless your hyper miling,  as long as you keep it under 3000 rpms range you'll be getting good millage.

[fuslit]

Wow, quite a bit of info to digest!

The clutch that was on it was from a guy who was racing it, it won't work against an o2a transmission anyhow.

I didn't get a chance to work on the engine last night, I had to meet with a client I do some web work for.

I've calculated the rpm band that I'll be in w/the tdi fifth and the current gear set. (fifth is my major concern as I'll be using it the most during my hr commute) I'm running 195x50xr15's with the o2a trans ACG gearset which has a 3.9 RP and fifth gear of .79 (.8 if you round up)

From the http://www.scirocco.org/gears/ page

Stock: At 65 in fifth gear the rpm's will be 3036 rpm
.756 tdi 5th: At 65 in fifth gear the rpm's will be 2869 rpm

If I get a g60 o2a transmission with a 3.6 r&p I drop the rpm's considerably.
with the Tdi fifth 2651 rpm) I'll have to keep an eye out for one to see what I can find. (I'm guessing that they are prob a tad hard to find though...)

I don't have the info on top of my head so I'll pull the info from it tonight. It's much bigger than a 1.6 turbo



Right now the engine has a three notch head gasket on it, I haven't pulled the head (I should just to be sure everything is ok) but I'm debating...

We'll see how much progress I make tonight.

-Todd

[zukgod1]

So really, unless your hyper miling,  as long as you keep it under 3000 rpms range you'll be getting good millage.

This backs up what I have physically discovered.
If I can keep it below 3k my mileage is much better.

[zukgod1]

What turbos are those Todd?

[fuslit]

Off the top of my head, I believe smaller one is a k14 (eco diesel?) the larger one is a k24 from an audi 5000 (I think). I'll get the #'s from the larger one tonight. It's the one I plan on running on this particular swap, I've gotten rid of the smaller turbo, but I do have a similar sized one which I got w/this engine.

Alot of this project is 'trial and see how it works' so I'm sure i'll be changing things around from what I initially thought would be 'ok'.

-Todd

[zukgod1]

If the smaller one is a 14 than the larger one is either a 26 or a 27.
If your using the OE intake and exhaust manifolds the larger turbo isn't going to fit (if it's a 27). The 26 will fit with some grindage on either the intake or the compressor.

If its a 27 (which is WAY larger than a 26) it wont fit at all unless you go custom manifolds.
Also you will hate the larger turbo for anything other than 3000+ RPM's.

If the turbo that came with the engine is a 24 and the larger turbo is a 26 take the exhaust housing off the 24 and have it machined to clear the larger wheel on the 26 exhaust side so you can still get a good spool and have the larger compressor as well.

[Dr. Diesel]

that small turbo is your friend.

[zukgod1]

that small turbo is your friend.

Exactly what I was thinking.

[fuslit]

I took it part again, tore it down and separated the head from the block so I could make sure the head and pistons were ok.



you can tell where at some point the valves were on the pistons (perhaps when I took the belt off?) while there is marks in the carbon, there really is no 'indent' into the piston.



I feel better about moving forward with the rest of it, not that I was worried but it would be kinda sucky to get everything together to find that a piston is/was hosed. Everything appears to be good to go.

Found a different oil filter holder which has a turbo oil line part.

Can you re-use head gaskets? The # on the one that's in it is 285 049

I pulled the info off the turbo I might use (a k24 I think?) I'm ok with it taking a little while to spool (at least I think I will be at the moment) if not I've got a k14 I can put on.

anyway the info tab is three lines... and in German so it can be a puzzle to figure out what it is. I haven't had a chance to go through it.

K *scratch so I can't read* NR: 069145703
ALT NR: 829180331
AUSFÜHRUNG: 5324 970 6081

I've got an adapter plate that will allow the turbo to be hooked to the current exhaust manifold I have.

Now I'm satisfied with the head and block, I'll start cleaning things up to get things ready for the 'build up' There are a couple seals that have small tears in them that I want to replace since I've got it down this far. I pulled the tdi flywheel from the tdi block and it should bolt up with out any problems! I'll call up the machine shop I use and have it resurfaced and start cleaning the transmission up.

I'm starting to compile a list of seals and bits I need for the build of the injection pump, block and transmission.

-Todd

[zukgod1]

Can you re-use head gaskets? The # on the one that's in it is 285 049

No you cant.
Get a metal AAZ head gasket according to your piston protrusion.

I pulled the info off the turbo I might use (a k24 I think?) I'm ok with it taking a little while to spool (at least I think I will be at the moment) if not I've got a k14 I can put on.

anyway the info tab is three lines... and in German so it can be a puzzle to figure out what it is. I haven't had a chance to go through it.

K *scratch so I can't read* NR: 069145703
ALT NR: 829180331
AUSFÜHRUNG: 5324 970 6081

I've got an adapter plate that will allow the turbo to be hooked to the current exhaust manifold I have.
-Todd

Take a pic of the manifold and turbo will ya?
The mount to be specific, I'm curious why you would need an adapter to mount a stock turbo is all.

The k24 will be ok for ya I'll bet, I thought mine was fine till I snapped the shaft (twice).

[fuslit]

Can you re-use head gaskets? The # on the one that's in it is 285 049

No you cant.
Get a metal AAZ head gasket according to your piston protrusion.

I thought that was the case, on the head gaskets, I'll have to measure the piston protrusion and figure out what metal head gasket to get (although since I want to push a bit more boost, I'm thinking that it might be better try and lower the compression ratio with a wider hg. another thing I need to research I guess)

Take a pic of the manifold and turbo will ya?
The mount to be specific, I'm curious why you would need an adapter to mount a stock turbo is all.

The k24 will be ok for ya I'll bet, I thought mine was fine till I snapped the shaft (twice).

The reason the turbo needs an adapter is this is not a stock vw turbo. so the bolt holes don't line up correctly to the vw turbo diesel manifold. (may be other types of manifolds, i'm not really that knowledgeable in this area)






It bolts up to the stock manifold with the adapter in those pics. I started to do that last night but got sidetracked pulling the rest of the engine apart. . .

Hopefully I won't snap the turbo's shaft, how much boost were you pushing when that happened?

-Todd

[zukgod1]

Aw there ya go, it has a T3 foot on it. Makes sense now.

Did you make that plate?
Can I pay ya to make me one? Seriously..

At the manifold I'm running about 27 psi on the top end with my 26/24 but usually it tops out around 22psi.
Before the intercooler and when running the k24 under hard accell I could touch 40 psi (shock).
At that point is when I decided I had better get a FMIC as I was pushing the turbo WAY past it's efficiency range. Then afterword's I could just touch 30 on a good day so I upgraded the FMIC to a larger core and toasted the turbo shortly there after
I know it was due to my driving style so after the first turbo I turned the pump way down and drove nicer and yet the second turbo snapped as well. I didn't know the condition of the second turbo (do now) so I had to just drive nicer. It snapped on level ground with the cruise control set @ 72 mph.
Now I have a hybrid 26/24, the 26 has the same dia shaft so I'm driving it nicer again. I'm going to change over to a T3 (thats why I need that adapter) to gain the larger shaft and also for parts availability. It's hard to get anything other than a rebuild kit for the k series turbos.

[fuslit]

Aw there ya go, it has a T3 foot on it. Makes sense now.

Did you make that plate?
Can I pay ya to make me one? Seriously..

I did not make the plate, but I was planning on making a few templates of it. It would be fairly easy to make up I'd imagine, I've got the majority of the tools needed. I could trace it out on some cardstock and send you a template if you want.

At the manifold I'm running about 27 psi on the top end with my 26/24 but usually it tops out around 22psi.
Before the intercooler and when running the k24 under hard accell I could touch 40 psi (shock).
At that point is when I decided I had better get a FMIC as I was pushing the turbo WAY past it's efficiency range. Then afterword's I could just touch 30 on a good day so I upgraded the FMIC to a larger core and toasted the turbo shortly there after
I know it was due to my driving style so after the first turbo I turned the pump way down and drove nicer and yet the second turbo snapped as well. I didn't know the condition of the second turbo (do now) so I had to just drive nicer. It snapped on level ground with the cruise control set @ 72 mph.
Now I have a hybrid 26/24, the 26 has the same dia shaft so I'm driving it nicer again. I'm going to change over to a T3 (thats why I need that adapter) to gain the larger shaft and also for parts availability. It's hard to get anything other than a rebuild kit for the k series turbos.

That sounds like quite a bit of boost to be pushing for sure, I've got a large FMIC (I'll see if I can dig up some pics of it) but I haven't decided to use it or not. Perhaps I should re-think that if you are having issues snapping turbo shafts.

I do need to figure out what type of Downpipe/IC pipe setup I'm going to use, Once I finish working on the engine I'll start working on that.

-Todd