Turbosmart solonoid replacement for N75?

[S2central.net]

Good to know you got the wacky 2-port config works on S2, but I for one would be setting it up a single port initially - just as a hardened replacement / upgrade for N75 without any plumbing changes first of all. The longest journey starts with one step

[GazzaG60]

first did this a few years ago on a subaru. went from a tdo5 to a t04R a big change.

the way that audi do it is like you would with an internal gate. there must be reasons for it but for me one of the real benifits of an external gate id being able to balance the pressure both sides to eleminate or almost valve creep. if you put equal force top and bottom then it wont move. remove the top pressure and its open instantly.the response to spool is improved especially when in 4th and above as the gases in these gears lift the valve creating lag. sure you all know how it works anyway.

i used the setup stated with my car in standard form using motronic and tiny turbo k24 and it impoved spool and general performance. many times more steady and better response. thats using the eboost. i love ebc's and they can only help as long as you know whats safe and what isn't.

i have seen blitz,hkz,greddy,apexi,turbosmart,MRT boost controllers and id say i think the solenoid on the turbosmart is the best one.

[S2central.net]

Gazza - with you 100% on the wastegate creep... Audi actually ran them this way on some I5T engines - pretty sure MB and MC - and I've seen it done by Audisport on the S1.

Did you need a 1-way valve for your 2-port setup or was it OK just connected directly to compressor outlet - ie before throttle body, not after at 'in' the IM ?

[S2central.net]

Meant to add - I want to think about some possible failsafe considerations on the 1-port and 2-port setups... Reduced WG creep is going to be great, but only if its not a major risk in the event of solenoid failure. Need to get my head round it...

[S2central.net]

Have just ordered one... £63 plus postage and VAT - I wont get to play with it for a couple weeks so that gives me time to do some homework.

[Jamo]

Let us know how you get on

[merlin's S4]

Let us know how you get on

Agreed! Sounds very interesting!!

[newsh]

So what we're saying is the solenoid valve will actually replace the normal N75 and run off the Motronic pulse signal from the ECU?

The e boost Controller looks like fun though, loads of different adjustments..

[S2central.net]

Doing some late homework and writing up some fundamentals that will be shared when ready...

Yes I think that TS device can replace the factory WGFV if plumbed the same way. Assuming the Motronic is OK with resistance of solenoid circuit. Some remapping may be required if the TS device operates much more rapidly than what Motronic can adapt to.

I've looked at both the dual port configurations in the TS manual and they are absolutely failsafe in same way as factory single port setup. My favourite of those dual ports is the one without the T-piece... This has fantastic potential to reduce WG creep giving faster turbo spool - without having to take on a beefier WG spring but its for certain that remapping will be required to make that work. Not horrific.

Actually you could plumb the factory WGFV for dual port operation and remap accordingly as well - I'd simply never considered it before but you could.

As to the actual eBoost2 controller - it has some nice features as these things go, but its biggest limitation is that you can only set it for one of three max boost profiles - the controller has no knowledge of engine RPM or throttle position. This target boost MUST be safe across the rev range at WOT and so this device will not allow you to make maximum torque in the mid range. Lets say we have a turbo with a compressor map that shows we can run to 1.5bar at the redline but that it could take 2bar boost in the mid range... On this eBoost device you'd have to set it for the maximum safest boost level - 1.5bar - leaving lots of potential oomf on the table but making a nice flat torque profile all the same.

Paul

[Mark Halligan]

but its biggest limitation is that you can only set it for one of three max boost profiles - the controller has no knowledge of engine RPM or throttle position.

Paul

I think you are right about the throttle position, but going by the installation manual doesn't the yellow wire pick the rpm?

[Jonas_R]

@s2central

Very interesting, think I will have to try it when my car gets mapped

[GazzaG60]

its a compressor out.

basically i have the solenoid, on the inner wing . pipe from turbo pipe from top port pipe from bottom port and t-piece. not tried method 2 as im happy with method 1.

the eboost is ultra controllable but i still use mine with 1 boost profile. basically you set when you wan to open the top port and then the max boost in simple mode. by doning this you cna have a nice n easy boost delivery from low to high or engineer a spike in the middle.

to answer the question with the k24 i spikled in the low to mid range then dropped off to avoid fireball. with the sc61 i have it ramping in hard as its more laggy the flattening at the top to a slight rise if you know what i mean. i currently run more boost at the top that mid range. having said that im only at 1-25bar.

yuo may be looking at the ebbost 1 the old version asd the eboost 2 has 6 individual boost maps if needed.

hope this is understandable.

i also use http://www.perrinperformance.com/pro...ory=9&model=23

and http://www.defi-shop.com/product/bf/bf_top.html

i have the older pod and it fits the audi perfectly not blocking the speedo or rev. only the clock

[S2central.net]

Paul

I think you are right about the throttle position, but going by the installation manual doesn't the yellow wire pick the rpm?

Oh I've just realised that i have been working off the older eBoost-40/60 manual that Jonas posted to understand that solenoid setup. There is definitely no RPM signal into that controller - see page 7 on the PDF that Jonas posted.

My bad for calling it the eBoost2 - which I guess is the more modern version and hence some coverage for RPM. I gather they use the same solenoid valve.

[S2central.net]

Thanks to Turbosmart, this forced me to capture some fundamental aspects of wastegate and WGFV operation. This took a long time to draw and animate - enjoy.

Attaching in a printable PDF format and a ZIP which has a Powerpoint slideshow.

I could make it a bit more elegant and pretty with more time, but for now I think it is functional and correct... Happy to take comments / corrections from others to make this better if I can.

[HPmuirt]

Another interesting diagram Paul

For me, as well as confirming the basic operation of the system, it raises the age old question of the WG spring pressure.....

Running as I do a stock S2 with your homefries and so running between 1.4 bar (max boost) and 0.8 bar (red line boost) I cannot see any disadvantage to using a 0.8bar spring to lessen the boost creep and therefore give a faster spool.

The spring would never allow more boost than the engine is prepared to give at any rev range, even when in 'limp home' mode. So I guess the only question is....is it a bad thing to have 0.8bar boost for limp home mode

I know this may be slighly off topic, but I was following this thread with the thoughts of changing the N75 and the WG spring to decrease spool time and improve the safety of the N75 - which I thought this N75 replacement thread was all about, but now it seems to include the use of ricer-stylie boost controllers etc

Bring back the carburettor.....I fully understood the dynamics of that

Cheers n

Si