How would I go about running the standard EBV with an external wastegate

I currently have an Tial external wastegate with a 10PSI spring and am thinking about running the standard EBV for a while to get back the ECU safety features (ie knock sensor boost reduction). I currently have an EBC set to 1.2bar

Will this work? As a factory actuator is .45 bar and my wastegate is more like .7bar will it all go wrong or is this irrevalant and the ebv will open when the ECU gets to the desired boost pressure? and overpower the 0.7bar spring or would I need to buy a Tial gate spring at .45bar same as the factory actuator?

you would need to get a .45bar spring, as the ECU doesn't see boost. It works on the basis that the wastegate is set to 0.45bar and just open the circuit for X amount of time. So if you had a 0.7bar, you would end up running 1.3bar via the EBV

And that would be with an overboost beyond 1.45bar right, which is what the normal turbo overboosts too?

Or is that overboost more the rubbish standard actuator and will the external not overboost - ie chip will hold it at 1.3bar?

Just try it and see, will be interesting how well it works. How well does the stock system work? I know its the same basic design as a Punto GT and the're terrible.

Why would you want such a downgrade? You're car isn't detonating is it?

Your running an Evocars chip?

In that case it will boost to way beyond 1.45bar! more like about 1.7bar!

I would like to run the EBC and EBV togther if I can. I want the multiple boost settings of the EBC but the ecu controlled safety features of the EBV/ECU

Just thinking about how I might make it work

Yeah begbie, evo cars chip

Yep, if you run your .7 bar actuator with the evocars chip and EBV, say hello to 1.75bar boost!

Well the boost will cut at 1.5bar once I max the map sensor so thats the end of that idea

Just be easy with your right foot and keep an eye on the gauge.

SO the only reason to use the EBV is to let the ecu reduce the boost under detonation? It would back off the timing though. I really wouldn't worry, you'll be able to hear it. Maybe get a knock link and see if its even worth it.

Doesn't it also adjust boost based on intake temperature and fuel quality? Or is that incorporated in the whole 'knock' concept?

Still very confused with this Begbie.

You say that ECU don't see boost. However checking the turbo Base pressure map (and the turbo cutoff pressure) on TunerPro, it specifically has boost values. Now, maybe the creator of the XDF (say definition file) for the map has put values that are meaningful for the tuner, whereas the ECU "sees" these values -0.45bar but I don't know.

Having said that, my RR session engine reached almost 1,8bar (on a .9bar tightened actuator )

care to elaborate a bit more?

V.

The ecu sees the pressure via the map sensor, but doesn't use it to control the EBV. It uses a duty cycle to control the EBV which is in the ECU, so in theory while the ecu sees boost, the ecu doesn't use the boost value to control the EBV

OK, makes sense (sort off)
However, when the ECU decides to send the pulse/duty cycle whatever you want to call it to the wastegate to lower the boost, surely it checks after a wee bit to make sure that the pressure is down, no?
Or put it another way, if pressure is still high then it will send the signal again, no?

BTW, what are the chances of my map sensor underreading?
I was confused as to why the RR came up with 1.75 or so before the ecu got into cutting injection (or ignition). Trying with the same settings as of Fridays RR session, I cannot get my barnacle widget to display more than 0.8bar. Will have to fit a good quality boost gauge to monitor me thinks.

V.

Vas: The way this works, the ECU sends pulses to the EBV. Each pulse will bypass some of the air going to the actuator. So if the ecu stops sending pulses, it will be the same thing as having a direct connection between turbo pressure outlet and actuator. Giving you baseboost.
So what the ECU does when lowering boost is probably it just stops sending pulses to the EBV.
The duty cycle is a measure of how often you pulse of availible time. 100% duty cycle means you bypass the air 100% of the time - the wastegate will never open and you will have the maximum availible boost that your turbo can give. A 50% duty cycle means that on 100ms you send a pulse every 2ms - the wastegate will open less (but will open).


If this works according to begbie, its a regulation-system without feedback. Wich imo is crazy to have on a turbo car. Since pressure will be different on diferrent altitudes and temperatures. The most crazy thing is that the car actually has a sensor for pressure. The MAP could be used for turbo regulation feedback. So if you hook up a good aftermarket ecu you will probably be able to control boost a lot better.

Saint: To get it working with a different type of actuator. You will need a remap.

my thoughts exactly Fuel...
Maybe what Begbie mentions is true on the 20VT (that hasn't got a map sensor) and ours uses some sort of feedback loop...

V.

I'm telling you the EBV doesn't know what boost your running, which is why the EVOcars chips states to keep base boost at 0.45bar.

If you put a 1bar actuator on and ran the EVOcars chip you would be looking at 2bar boost (well the ECU would cut before hand) because this is what the chip is designed to do

Its a simple open loop system, quite common for factory boost controlers around that era. Getting a closed loop system to work well is not as easy as you may think and it costs more. The cheaper aftermarket ones are not that great either. Its only the high end controlers that have a true closed loop system that works well.

Fiat would have decided the cheaper system was adiquate.

Sure, its a bit more complex (software wise), but with the resources car companies have, it shouldnt be a big problem.
Saab has been using closed loop regulation since 1982 on all their turbo cars. (APC)
We have loads of these APC systems here in sweden, could probably get one for less than 50 euro.
EDIT: Yes it has knock-detection/knock-regulation :-)