Thread: 25 PSI boost on 300Tdi

I wonder if they'd be any advantage in fitting an upgraded wastegated turbo instead of a VNT? It seems that a Disco Potato could be had pretty easily and then just a matter of getting a manifold.

Originally Posted by B92 8NW

I wonder if they'd be any advantage in fitting an upgraded wastegated turbo instead of a VNT? It seems that a Disco Potato could be had pretty easily and then just a matter of getting a manifold.

200Tdi Disco manifold or one of MTQ's 300Tdi manifolds and you can use whatever turbo you want.
MTQ use a TD04 Mitsubishi and they run well but it is fairly old school these days with BB's and VNT's.

I was going to offer a customer a turbo swap as they have a Bruce Davis turbo setup and apparently it needs a little TLC according to their mechanic, but, well, I'm done playing with the Tdi.

Originally Posted by B92 8NW

I wonder if they'd be any advantage in fitting an upgraded wastegated turbo instead of a VNT? It seems that a Disco Potato could be had pretty easily and then just a matter of getting a manifold.

A disco-potato is not a suitable turbo. It's designed for low boost petrol engines, also works well on larger low boost diesels (i.e. toyota, nissan 4.2's) but is completely the wrong turbo for a 2.5 that needs more pressure. 25psi is basically off the map on a GT2860RS.
There's a navara board I visit where a member changed his YD25's VNT turbo (GT2056V I think) for a disco-potato. Turned it into a slug that needed revved out to build any boost and get anywhere. His videos showed 11 seconds from 30-60mph.

VNT turbos are designed to run high boost, they don't hand out compressor maps but 25+ psi is common on modern diesels.

I've also had had Merc cab over ute as a work vehicle and it had a 2.2 T/D that went like **** off a shovel,I don't know what turbo it had but it left every other T/D I had behind.It must have been a VNT as you put your foot down and away it went,I'd happily fit one in my defender,like dougal said the original Tdi turbo is not a very good one,at higher boost it flogg's the air instead of pumping it. Pat

Originally Posted by rovercare

Yep, cracked chassis is common as on them, the Nissan vs Tojo thing, I'm aware of a few studies, that show the Tojo to be a far better lease vehicle, considering large purchase price, but far less dowtime due to reliability, so that's what they have in the open cut mines here

Hmm 25psi, I wonder what this VNT turbo is efficient to

Actually I serviced lease vehicles once,never ever again and the defender was a clear winner regarding purchase price and maintenance.Toyota's were waaaaay above but the operators were cruiser men so cruisers are what they got,there is no way on this earth tojo would let any other maker,heaven forbid LR take over thier supply of site vehicles,eight out of ten Tojo's sold are company purchases.Trust me,the defenders did everything ask of them. Pat

Originally Posted by PAT303

Ilike dougal said the original Tdi turbo is not a very good one,at higher boost it flogg's the air instead of pumping it. Pat

Gee thanks. But I think it's Bush65 that you're really talking about.

I had a spare few minutes today to start installing the hardware... correct my procedure if it's wrong but I've already got the intercooler in, I was going to increase the boost to 18 PSI first, monitor the EGTs for a few weeks to get a feel for how much extra fuel I can add, then turn up the fuelling. I've spoken to a good Bosch agent in Melbourne who tweaked my 200Tdi Disco and they've advised to leave the boost compensator adjustments alone, and only adjust the bolt at the back on the end where all the pipes emerge (or let them do it!!!).

First major problem is reaching the actuator rod, crap compared to a 200Tdi. I'm thinking about removing the whole manifold and setting it with compressed air, or getting a turbo shop to check it over and set it for me. They can do this on the bench?

Input welcomed please

Originally Posted by PAT303

I've also had had Merc cab over ute as a work vehicle and it had a 2.2 T/D that went like **** off a shovel,I don't know what turbo it had but it left every other T/D I had behind.It must have been a VNT as you put your foot down and away it went,I'd happily fit one in my defender,like dougal said the original Tdi turbo is not a very good one,at higher boost it flogg's the air instead of pumping it. Pat

The VNT a few of us were looking for was off a small Merc commercial, the same one that is being used by the UK power up merchants on the Tdi.