Turbo-diesels...

[TomM]

On turbo-diesels, can you just stick in a Bren device and up the boost?

[Wak]

It was only a matter of time before someone asked :rolleyes: :D

[shadow21]

Hi,

Beware: turbo technology is, of course, the same on diesel and petrol cars (so, you can up the boost the same way), but the diesel technology by itself is "anti turbo"

I mean: diesel work with high comp values, so, to make a turbo AND a high compression ratio work together is by itself a challenge. That's why diesel cars can't work with high boost (or big turbos)


I wouldn't touch it!

Cheers

Fabien

[Jason]

Forgive me for eing ignorant, but how does the bren device work??

[Phill]

My daily 'back and fourth to work' is a turbo diesel cav - upped the boost a little on it and gained 13bhp, much more drivability and it's better on juice!! Can't complain about that really!!

It's not quite as simple as upping the boost on most diesels though cos to get the power the fuelling needs adjusting too.

What car is it mate??

Well happy - £38 worth od diesel - 550miles :D

Oh i'm going to find it hard once to 200 is on the road.

[dave_s13]

How did you do that then m8???

And why does upping boost give you MORE mpg?? You'd think the opposite would be true.

Dya reckon I can do it on my 405TD???

[shadow21]

Originally posted by dave_s13
How did you do that then m8???



On my Opel Astra 2L TD, the turbo is a Garrett WITH ADJUSTABLE ACTUATOR !! :D :D :D

But as I said before: I wouldn't touch it by myself (even if it's tempting :rolleyes: )

You can use the "washers" trick to increase the boost on most turbos...

Cheers

Fabien

[TomM]

Originally posted by Phill
What car is it mate??
I've not got a diesel yet, but I'm just thinking of lots of options. 'Cos I'm living in Barrow but travelling back to Manchester ATM (and lots of driving over the w'end) I'm spending a fortune on fuel - I reckon about £50 this weekend alone. :eek: This mileage makes another 200sx unlikely for the near future.

Options:
1. Buy a turbo-diesel (ie 306) and up the boost :)
2. Buy a 200sx and use the train to go long distances :(
3. Keep the Bravo for the next 5 months (until I escape Barrow :) ), as if I sell it, I'll lose £££s, and then buying another car, I'll lose £££s (just from dealers' profits, etc) and all of those £££s will pay for a good few tanks of fuel. Add to that the fact that I need another 200sx at some point, and buying yet another interim car makes even less sense, as it's jsut all more wasted cash, even if it does save me a little at the pumps.


Confused... :(

[Martin T]

The reason that fuel economy goes up is because a diesel works nothing like a petrol engine. In all diesels with out common rail/Direct injection, the amount of fuel going in has nothing to do with the revs or airflow. Most dont even have a throttle butterfly.
The amount of fuel dumped in is proportional ONLY to the amount of throttle you use, so at low revs if you give it some you are guarenteed to be over fuelling, hence the black smoke that most diesels spew out on acceleration.
By upping the boost you have no effect on fuelling, but you are getting more air in to burn the fuel properly, and et voila, more performance and less fuel usage as you dont need to accelerate for as long.

[Ivanski]

I don't think you can get the fueling 'wrong' on a diesel either, lean just means less power. In fact TD's are deliberately run lean to stop black smoke. You just need to add more fuel to get the power up. :)

The VW 110 bhp TDi runs 16psi as standard IIRC and has a nice VNT turbo :D There's a lot of info, (which is VW biased) at the TDi Club FAQ (http://www.tdiclub.com/TDIFAQ/)

There's a nice section on injector swaps, but mention fitting a dump valve and you'll get a slap :p

Cheers

[vega]

Originally posted by Jas
Forgive me for eing ignorant, but how does the bren device work??

Inside the Dawes Device is a spring and a ball baring. The tension on the spring is adjustable, to vary the amount of pressure the baring can withstand from the turbo manifold before letting air pass. In doing the this, the wastegate stays completely closed until the Dawes effectively *dumps* the air to the actuator's diaphram, opening the wastegate to slow down boost. As pressure decreases, the Dawes will close again until more pressure is spooled, so on and so forth......

[Dave H]

I did this on my 306TD, upped the boost with a dawes device and got my friendly mechanic to increase the fuelling, midrange acceleration was amazing, surprised lots of supposedly faster cars.

I ran it like this for 8 months and 20k miles, with no ill affects, sold it to a mate and it's still going strong

Not much more smoke although at night if you looked in the mirror when you booted it and a car was following you it did seem to get quite foggy!

[vega]

My astravan does that smoke thing anyway :eek:

[kingdeacon]

i had a nova van td, with the boost put up. and for what it was it went very well

[Martin T]

Originally posted by vega
My astravan does that smoke thing anyway :eek:
Don't all Vauxhalls, diesel petrol or LPG?:D

When I boot my van, all I get is a momentary wisp of smoke, then its gone. Must be coz of the common rail injection system on it.

[dave_s13]

Originally posted by Hotrod
I did this on my 306TD, upped the boost with a dawes device

Did your 306 have the same engine as a 405 TD????

If so I'm intrigued as how you did this exactly, with instructions and photos if possible:):)

cheers

[Dave H]

Yep same motor, don't have any pics or anything but the dawes was fitted on the actuator hose as normal, I didn't increase the fuelling myself, mate who's a mechanic did it, wouldn't have known where to start, only took him 1/2 hour to do it though so can't be that difficult.

*Disclaimer* if you blow it up it's not my fault *Disclaimer* ;)

:)

[Nismo_Freak]

Alot of diesel trucks here in the US have been "souped" up. Mounting larger exhausts, larger turbos, more boost, fuel, propane injection, etc. all work on the diesels. Locate Bank's website on the web. They do a ton of diesel upgrades.