External Wasgate's & VNT's?

[Os8472]

With my car withnin a few days of being back on the road and having an external wastegate I've started looking into how to set it up properply but I've hit a snag.

Normally when you have an external wastegate controlled by an electronic valve theres no internal wastegate in the turbo to worry about but with a VNT you have to keep the actuator or it won't make boost, now if I was just gunna run the boost pressure of the wastegate it'd just be 1 vacuum line split between the 2, with a bleed valve you'd fit it before the split but with an electronic valve you have 2 vacuum lines to the external wastegate.

How do I plumb in the wastegate, valve and VNT actuator?

Has anyone fitted an external wastegate to a VNT powered R5?

And before you say it, yes I have used the search function and Google and come up with nothing

[Andrew Cooke]

I put the VNT actuator to the manifold, engine side of the butterfly.

I used the boost controller on the wastegate, and connected that to the intercooler side of the butterfly.

[Os8472]

Ok but how do u raise the boost, I know mine would sit at 10psi til it got to around 4800rpm and then shoot up to 25psi+ ?

The waste gate has 7psi spring so map 1 will be 7psi standard timing good economy
map 2 will be 14psi slightly advanced timing
and map 3 will be 20psi and as far advanced timing as safetly possible

well that was the plan any way.

[Os8472]

Ah what a dumbass, I know how to do it, all I gotta do is setup the VNT actuator to run 20psi normally then control the wastegate with the electronic valve to lower the boost to where I want it, duh how did I not think of that

Thanks Andrew, all I needed was someone to bounce ideas off of, damn my useless brain, can't figure anythin for itself (hits with beer can)

Brain: Thats it I'm outta here (footsteps followed by door slam)

[Adey aka Ewok]

why 3 different maps?

[Os8472]

Several reasons, I don't wanna run around on full 20psi all day, I want some reliability so day to day 7psi will be enough, 7psi means using less fuel so better economy, 20psi would be too much for a long track session so 14psi gives me a happy medium of power and long term reliability and 20psi is for out and out drag runs

[Scoff]

I think there might be some confusion, retarding ignition timing will not save you fuel, leave the timing optimal on all 3 maps Really you only need one fuel map too, but I suppose you could have a very lean cruising map to give you a switchable fuel ecconomy mode!

Maybe 3 settings: 1) lean cruise map, minimal boost. 2) richened up cruise map, meduim boost. 3) richened up cruise map and maximum boost.

[Big Steve - Raider]

20psi is for out and out drag runs

I thought you never ran your car on the strip?

Can you not use a VAG N75 valve to control the boost to the turbo like Dave Walker did on my Emerald ECU's 3 maps in the Clio??

[Os8472]

I think there might be some confusion, I think what you mean is 3 different boost settings, you only need one fuel map

Nope no confussion 3 maps, 1 is a lower power cruise map with stock timing to make the drive smooth, economical and reliable, map 2 is the same as map 1 but with more boost and abit more advance on the timing and map 3 is full boost and as much timing advance as safe, the fuel map won't change bu the ignition side will, its just the turn of a knob to change the map on the fly so I went that, I coulda added a second knob so I could have 3 different boost settings depending on what type of fuel I'm using for example, 1 would be 95ron, 2 would be 97/98ron and 3 would be bio ethonol

I thought you never ran your car on the strip?

Can you not use a VAG N75 valve to control the boost to the turbo like Dave Walker did on my Emerald ECU's 3 maps in the Clio??

Dunno where you got that idea, if it hadnt been for the strip and meeting The Master at Santa Pod I'd never have started this project.

How much is a VAG N75 then? and what can it do? and more to the point what is it lol?

[Scoff]

I misread what you ment sorry, and then edited my post.

[Big Steve - Raider]

How much is a VAG N75 then? and what can it do? and more to the point what is it lol?

It's basically a boost control solenoid.

Have a read HERE.

If you have a look at the K3 manual you'll see it's connected to pin 21

[Os8472]

I misread what you ment sorry, and then edited my post.

Yeah saw that the second I posted my reply lol

It's basically a boost control solenoid.

Have a read HERE.

If you have a look at the K3 manual you'll see it's connected to pin 21

Interesting, sounds much the same as the valve I already have, I'll do some more research, thanks bud

[Scoff]

There remains some confusion though, you can't have 3 different ignition maps and expect the same fuel map to work all three, since one will affect the other. I see what your trying to achieve though, it's a good idea

[Os8472]

There remains some confusion though, you can't have 3 different ignition maps and expect the same fuel map to work all three, since one will affect the other. I see what your trying to achieve though, it's a good idea

When you turn the knob it not only changes the ignition map it also changes the fuel map aswell as the rev limiter settings, overrun cut, any launch control settings and no end of other stuff, its like having a car mapped to 7psi then changing the whole ECU for 1 thats mapped to 14psi, proper cool little trick, should make passing emission tests at MOT time easy aswell as you could have your setting 1 to fuel perfectly for emissions then the other 2 ramped up for power

[Scoff]

Thanks for the lesson on aftermarket management, believe it or not, I have a rough idea how it all works

But what I'm getting at is that you said you'll only have one fuel map (albeit replicated 3 times) and my responce to that is that you can't do that because fuel requirement changes with igntion timing. Maybe you just ment that the end result will be the same, bar the ignition. I still think you'll want to leave the igntion map the same on all 3 setting though

[Os8472]

Thanks for the lesson on aftermarket management, believe it or not, I have a rough idea how it all works

But what I'm getting at is that you said you'll only have one fuel map (albeit replicated 3 times) and my responce to that is that you can't do that because fuel requirement changes with igntion timing. Maybe you just ment that the end result will be the same, bar the ignition. I still think you'll want to leave the igntion map the same on all 3 setting though

Sorry didn't mean to sound patranising, I didn't know how much you know about the Emerald, that and I rubbish at explaining things, (damn brain, needs more beer)

I'm gunna give up cus I'm just digging a bigger hole lol

[Andrew Cooke]

what you need is a fully controlled VNT actuator, that way you could open it fully on cruise and improve the VE of the engine.

[Os8472]

what you need is a fully controlled VNT actuator, that way you could open it fully on cruise and improve the VE of the engine.

Is that like having a little motor that moves the actuator arm instead of relying on the vacuum?

[Andrew Cooke]

Is that like having a little motor that moves the actuator arm instead of relying on the vacuum?

yep

[Os8472]

yep

I think I saw somit about those when I was searching on how to plumb in the wastegate, I think it was about the porsche 997 turbo, they've got 2 VNT's, god knows how, 1 is hard enough to control

[markey b]

like on a modern turbo diesel??

[Ben]

Is that like having a little motor that moves the actuator arm instead of relying on the vacuum?

how would the motor be controlled? cant see the emerald system having a function for actuator control. or does it

[Os8472]

how would the motor be controlled? cant see the emerald system having a function for actuator control. or does it

Haven't a clue, I'll ask dave on monday, I gotta pop in and book the next mapping session

[Ben]

let us know how you get on. still after ideas on the best setup for my vnt too.

[Os8472]

let us know how you get on. still after ideas on the best setup for my vnt too.

Will do