Why no-one tried a sequential turbo setup on TDI?

Jim H

Active Member
Mar 6, 2009
214
1
Teesside
I'm sure the Vetra cdti had 2 turbos, a small and a big one. I can remember seeing a diagram of it.

What I'm surprised at is no one has fitted a supercharger to a diseasel. I have seen a marine 2-stoke with them but never a car. Since a diesel works at low revs I would have thought a supercharger would be ideal.
 

vroomtshh

Full Member
Sep 11, 2005
4,222
3
Dreghorn, Scotland
Not quite ;)

FP07EWH.jpg


Still on standard injectors..

Kev

On a diesel? Then you need a new rolling road operator ;-)

I'm running a larger turbo and larger injectors and not making that. My injectors were at something like 94% duty at 215bhp.
And that's a real 215 ;-)
 

jonjay

50 Years of 911
Jun 27, 2005
5,843
1
Essex
Sorry but if that is with stock injectors and no other fuel used even with extreme cam and head work those are bullshite numbers. No matter what mapping/hardware you do the injectors can only inject so much diesel given the duty cycle I/O .
I think those numbers are optimistic. However assuming that you can get around 12-15bhp extra from a cam and around 10 odd bhp on the head then it isnt that far off. The injectors are the limiting factor and bosio ones that give you around 25% more would be needed for that figure.
 

jabbasport

Guest
I swear these figures are correct.

Considering the turbo is GT25 based, peaking at 2.25bar and dropping to just under 2bar and the injectors are FLAT out..

Kev

PS. That customer's car has just been collected, but we have a demo one here which im happy to datalog, if anyone wants channels logging?
 

bobby singh

Active Member
Nov 2, 2006
75
0
Sorry to bring up a old thread i dont come on here alot..
Kev can you log channel 4 and 11 from 1500rpm to 5k
I've tried maxing out the stock injectors and could not get more than 230hp (even that was on a unsafe file)

Keeping the injection window safe i could not get more than 215 to 220hp.

I've also tried WMI and didnt increase peak power rather just held power abit better.

Bobby
 
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