Thanks Otis, a very useful and timely reply, as just been told much the same thing be ndy Simpson who posts here as well... he runs a K24 I believe and saw his temps last weekend wer nothing like mine, but then has an air-to-water intercooler with a front rad AND 26 ft of copper pipe to keep it cold :roll:
I don't have new rad and water temps do climb now and again, until that big Diesel fan cuts in (550W!!)...
Oil temps creep up far too easily to 130C, do you have an oil cooler..
Wanting to keep the Garret T2 or K14 for low-end pulling when ff-road and good pickup, but it seems the larger turbos really don't compromise this as much as folklore has it, certainly with the larger exhausts and some more fuel...
I have a T3 kicking about somewhere actually, but it ooks awfully large to fit to the VW JX Diesel Vanagon style manifold :roll:
I have a larger oil/water heat exchanger (ie. "cooler") than stock AAZ. It's from a 2005 Passat PD130. But frankly, it didn't do very much for oil cooling when I had the K03 turbo on there. I was disappointed (and my wallet was significanly lighter...).
However, now, with the big T3, oil temps are acceptable (if a bit hot) with the PD130 oil/water cooler. Probably a sandwich-plate adapter for the oil filter mount, with air-cooler, would cool the oil better. If I had 130 c oil temps, I would take immediate drastic action... TransDapt makes a sandwich adapter that will fit the AAZ - part number 1313.
I have an exhaust manifold from a 1.6TD Golf, with an adapter flange to fit the Mercedes T3 turbo. The exhaust manifold is mounted upside down, and the turbo housing re-indexed. With the exhaust manifold flipped, there's plenty of room to mount a bigger turbo.
I'm not sure how easy this would be to do on your setup - I bet your engine is mounted at 50 degrees. My engine is mounted at 15 degrees, using a Kennedy adapter plate, which may give me more room for experiments without losing ground clearance.
This 1.6TD exhaust manifold has a trapezoid flange, rather than the triangular flange for the K03 turbo that was on the original AAZ manifold. If you look at the two exhaust manifolds side by side, it's remarkable how restrictive the AAZ manifold is. Just a tiny hole to feed the turbo and pass the exhaust. I suspect the K14 exhaust manifold on the AAZ has the same restrictive tiny flange as the K03...
I suspect a big part of my cooler running is the reduction in backpressure achieved from the 1.6TD manifold and the big T3. Remember, this Mercedes turbo is a bigger T3 than was used by VW on the 1.6TD. I have read on this forum that the A/R for the VW T3 is 0.30, and the T3 for the Mercedes is 0.48. Possibly the VW diesel T3 would be a better turbo to use for low rpm spooling and still run cool, but I have no empirical data on that.
My intercooler is air-water with a dedicated front-mount radiator, and two electric pumps. (BTW, no copper tubes, it's all rubber... copper and aluminum make a nice corrosive battery in contact with water.) One of the pumps died, blocking all coolant flow (so the intercooler effectively became an inter-heater/heat sink). But it had no effect on my EGTs. The compressed air from the big turbo is really that cool. My intercooler is probably superflous with this present configuration.
To further make the point, I have some wiring that is routed much too close to the "hot side" of compressed air from the turbo, but surprisingly the insulation has not been damaged at all by heat. I really should re-route that wiring, but it seems to live there quite easily, emphasizing the relative coolness of the turbo's compressed air.
I appreciate your interest in low-rpm spooling that you get with the K14, for off-road use. And there are plenty of times that I wish I had an earlier spool. But of course you do have the granny-low gear in the syncro, and with the fuelling turned up, I expect that AAZ provides plenty of off-road, low speed grunt prior to turbo spool.
Mine seems to, anyway. I don't ever see more than a couple of psi boost in 1st gear, and maybe half a bar max in 2nd gear. Running NA is still adequate to get me started from a dead stop on some pretty extreme inclines, although as Andrew notes, sometimes I can't get into 3rd without good momentum. That's mostly due to the huge gear ratio gap between 2nd and 3rd in the wasserboxer 4-speed, I think, aggravated by my tall tires. Only in 3rd and 4th gear will I see 10+ psi of boost.
I also doubt that you operate the vehicle at anything like the elevation that Andrew drives, unless you're up in Scotland regularly (and even then...). That's why I noted that my data is taken at roughly sea level.
Best of luck with water injection, but your engine sounds like it's running so hot in so many ways, that I kind of doubt that W.I. is going to make a huge difference in all temps (EGT, oil & water). The more open exhaust manifold and big T3 turbo
has had an across-the-board drop in my own operating temperatures, but obviously at the cost of low rpm spooling. Nothing is for free.
Topic: EGT - What to expect (Read 5779 times)
