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

[vti-chris]

Positioning won't be that of a problem...there should be some space somewhere.

It would keep the stock boost to higher rpm...thus increasing hp at top end.

No clutch issues since no more boost will be run.

I don't know whether the stock injectors can work on high end...someone help here.

I'm a noob and just asking, so !!!

Something like 123d or 335d.

I know it must have been asked before but searched and found nothing specific.

 

[muddyboots]

I have a feeling Devonmikeyboy looked into a twin-turbo setup on his A3 ?

 

[vroomtshh]

I have a feeling Devonmikeyboy looked into a twin-turbo setup on his A3 ?

I think he did.

But I don;t think he went through with it.

I'd imagine that the cost far outweighs the benefits

 

[vti-chris]

What cost?
An extra turbo...custom downpipe.
If no remap is done...won't the ecu add the extra fuel on top end say from 3-5K?

The added turbo would be set to the same boost level...

 

[vroomtshh]

What cost?
An extra turbo...custom downpipe.
If no remap is done...won't the ecu add the extra fuel on top end say from 3-5K?

The added turbo would be set to the same boost level...

Turbo, downpipe, manifold (unless your planning on adding the extra turbo intot he downpipe)
If no remap is done, the car will run like a bag of spanners.

If you add this extra turbo, running the same boost level, would you go for a bigger or smaller turbo? And what do you hope to achieve by doing it?

 

[samc]

its been done, theres a mk2 golf on youtube running 10second 1/4miles with sequential turbos

 

[vroomtshh]

its been done, theres a mk2 golf on youtube running 10second 1/4miles with sequential turbos

On a diesel?

 

[samc]

yep lol smoker would be an understatement lol

 

[vroomtshh]

yep lol smoker would be an understatement lol

Got any links?

 

[vti-chris]

123d...second turbo mounted on the downpipe.

Why wouldn't it run.
Second larger turbo will spool at 3000 and keep it to redline...all i'm concerned is the fueling...will the ecu compensate to the increased flow on higher rpm at the same boost levels?

 

[vroomtshh]

123d...second turbo mounted on the downpipe.

Why wouldn't it run.
Second larger turbo will spool at 3000 and keep it to redline...all i'm concerned is the fueling...will the ecu compensate to the increased flow on higher rpm at the same boost levels?

So you;d fit a larger turbo than you currently have into the downpipe?

Isn't it normally done the other way around?

But then you need to figure a way of allowing the small turbo to flow more air (bypass etc)

The ECU won;t compensate ofor the fuelling unless you tell it to.

I'm not knocking your idea (in fact I'd like to see you do it). I'm just questioning your reasoning.

I thought that sequential turbos were to allow minimal lag while staill allowing maximum air flow at top end? Is that what you are trying to achieve? While thats a worthwhile achievement, I just don't see the need for it on a standard set up.

Even a 'big turbo' setup like mine still reaches max boost just after 2k rpm and (in theory) will flow enough air for 300hp.

 

[samc]

its not this 1 but what a beast... i'll keep looking
http://www.youtube.com/watch?v=_La6Zd6QAPs

 

[samc]

http://www.youtube.com/watch?v=JTH-JwqPSF4&feature=related

pretty sure thats the 1 all be it a polo(it was a while ago that i seen it) but cant find any info on it yet

 

[vti-chris]

A bigger turbo will have more lag...will flow much air to reach 300 but at what torque numbers?

I'm talking about keeping stock turbo for low rpm boost(which you don't have...with the large turbo i think!!!) and use a much bigger one running same boost but hold it until 5000.
Does yours hold full boost up to 4500-5000?...if so then there is no need for this talk.

I'm just beginning to learn diesels although i've had one for 10 years...regarding the exu adding fuel...why wouldn't it?
Doesn't it read air flow using the MAF to add fuel accordingly?
I don't think that the fueling is already set and unchanged from the factory...thus running same in cold and hot climates...this wouldn't work right.

 

[samc]

nope not that 1 either, i'll keep looking though

 

[vroomtshh]

A bigger turbo will have more lag...will flow much air to reach 300 but at what torque numbers?

I'm talking about keeping stock turbo for low rpm boost(which you don't have...with the large turbo i think!!!) and use a much bigger one running same boost but hold it until 5000.
Does yours hold full boost up to 4500-5000?...if so then there is no need for this talk.

I'm just beginning to learn diesels although i've had one for 10 years...regarding the exu adding fuel...why wouldn't it?
Doesn't it read air flow using the MAF to add fuel accordingly?
I don't think that the fueling is already set and unchanged from the factory...thus running same in cold and hot climates...this wouldn't work right.

Unsure on the torque at 300, but my last dyno run was 256/420 and that was just the initial map. Its got way more torque to come, by adding more fuel low down.

I'm making boost as early as the stock turbo is (and more of it too)

And it holds full boost high up. I'd need to wait til I get home and look at logs etc to say exactly when it'll hold boost until.

I thought it read from the MAP to adjust boost? I don'r have a MAF so it definitely doesnt read from that

The fuelling isn;t set exact, but I'm sure it'll only work within set parameters. A lot of this is going way over my head and isn;t something i've looked into yet.

Standard injectors will only flow enough for 220-230 at the extreme too so you;re always going to be limited by that

 

[vti-chris]

Yes i know.
Just found this on another forum.

 

[M1KEH]

The standard map won't supply enough fuel for the extra flow, only changes for small differences.

 

[Fl@pper]

love the way the polo changes gear just out the tree

 

[jabbasport]

Standard injectors will only flow enough for 220-230 at the extreme too so you;re always going to be limited by that

Not quite

Still on standard injectors..

Kev