VNT Turbo and Performance Mods - 300 Tdi

For anyone who is interested.

I went from 235/85s (31s) to 285/75 (33s) today and it made next to no difference in power, if anything it seems a bit faster :twisted:

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Originally Posted by Jock The Rock

Well it now flies, for a Defender :)

While we were at we wound the fuel up a bit more. It's now pulling 750 under a heavy load with a max boost of 17 psi

We gave the head an extra torguing sequence so it should hold up to the higher pressures. (40Nm - 60Nm - 60 degrees - 60 degrees and 20 degrees for the ones that need it)

The new head hasn't really done much, except help to cool it a bit. Being a newer head it has the extra cooling galleries

I hope to tweak the turbo a bit more so I can run closer to 18 - 19 psi

I'm not quite getting wheelspin on the tarmac yet, but it would rip it up on the gravel :twisted:

So anyone after a stock 300 Tdi head, complete with valves? (Done 105,000km)

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if you are after performance turner engineering in the uk does ported and flow tested heads for 500 pounds giving between 7 and 10 hp more but im not sure if it is a new head. Also have you thought about hood vents ect to draw more air through the full sized intercooler.?

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Originally Posted by Pedro

if you are after performance turner engineering in the uk does ported and flow tested heads for 500 pounds giving between 7 and 10 hp more but im not sure if it is a new head. Also have you thought about hood vents ect to draw more air through the full sized intercooler.?

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Hey mate

I have fitted one of them didn't really notice any difference in power although it did rev out a bit longer

I didn't end up fitting that intercooler, I still have to attack the situation with the cooling system

I plan on a big front mount and perhaps larger radiatior or a water to air setup

Hey Jock,

Finally fitted Diesel Gas to my tractor (camo disco :))

God its good, loving it, makes a massive difference cruising on freeways and hills!

Thanks again for answering all my q's way back, was a big help and deciding factor getting me to go ahead with it.

Cheers!

Thinking of doing a water IC as well similar to budley's setup (water ic)

Don't think I will go the vnt route (already blown my budget on this build :D), although never say never!

No worries mate

Glad to here your happy with it

What size exhaust are you running?

I have the standard pipes but with no muffler or res, its just straight out.

I don't mind the noise at all, the diesel, the muddies and exhaust are all pretty loud but its still quite ok for cruising. I would imagine the sound proofing is better in discos to defs.

I was thinking of going 3" but with a res at the back one day.

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Originally Posted by zuno555

I have the standard pipes but with no muffler or res, its just straight out.

I don't mind the noise at all, the diesel, the muddies and exhaust are all pretty loud but its still quite ok for cruising. I would imagine the sound proofing is better in discos to defs.

I was thinking of going 3" but with a res at the back one day.

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I recommend a larger exhaust, it opens up the rev range

I wouldn't recommend 3 inch. They sound absolutely horrible, I have a 3 straight through mufflers in at the moment and it has made little difference. I've spoken to a few people and the seem to think a 2.5 mandrel bent will do the job just fine

I had the front quarter panel off a while back. While I was at it, I decided to replumb the air intake from the base of the snorkel through to the air cleaner.

I went to the wreckers when I was in SA last year and bought myself a main intake hose from a 300 Tdi Defender. I used this and some 3 inch stainless mandrel bends and some straight 3 inch to do the plumbing.

The open hose is where the breather would normally enter the air intake. It now works really well as a route for any wires going to the roof rack

I didn't notice a huge difference in power, but from memory I gained about half a psi with the turbo :p

In the photos you can see the size difference between old and new

https://www.aulro.com/afvb/images/im...011/11/671.jpg

https://www.aulro.com/afvb/images/im...011/11/672.jpg

Would it be possible that the temp and lack of high end problem both be due to it running too lean on fuel.

I can't recall with diesels how it goes with lean mixtures, I know it burns faster so by rights will give you less power but should be cooler EGT's but may cause hotter base engine temps.

Start playing with the pump, and see what happens before stuffing about too much more as you may not need to do much to the radiator.

Also will the bigger intercooler do much for you until you get the higher boost pressures?

Cheers Casper

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Originally Posted by Casper

Would it be possible that the temp and lack of high end problem both be due to it running too lean on fuel.

I can't recall with diesels how it goes with lean mixtures, I know it burns faster so by rights will give you less power but should be cooler EGT's but may cause hotter base engine temps.

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Diesel 101: They always run lean until black smoke appears. Most diesels don't have any intake throttling. Excess air aids cooling. Over rich mixtures are the ones that cause heat problems.