john banks

How about a proportional flow control valve or a solenoid valve with a fast duty cycle between the turbo outlet pressure source and the inlet to the MBC? It would be controlled by the output from the throttle position sensor so that when the throttle was wide open the valve would present a restriction but when the throttle was say half way there would be half this restriction and when the throttle was closed there would be no restriction. The MBC would be set to a lower pressure to compensate. Offsets could easily be adjusted with potentiometers around the op amps - two would be required. Any thoughts? This would remove full boost at part throttle and improve driveability.

Luke

Jesus, John, Leave it alone !!!!! I bet you've had your toaster apart!!!!!

Be Lucky

Luke

john banks

How did you guess about the toaster? Made it work again though

babber

John,

I want one of those mate

I'm amazed at the time you spend on here considering your busy career!!

Cheers Phill C

john banks

Does anyone have anything to say apart from about my toaster

EvilBevel

Hehe

As long as john sticks to opening up inanimate objects ...

But all jokes apart ... I admit that this is being a bit over my head, but you just may be giving too much attention to TPS. The fact that you are dealing with a turbo car makes the TPS bit rather unpredictable IMHO.

What we *really* need is - no matter what turbo - a closed loop feedback device that lets us dial in *exactly* what boost curve we want (given the obvious limits).

I would want a device that lets me say x.x bar at x rpm, then x.x until y RPM, then trail off to x.x bar at z rpm. The controller should then sort it out.

Ideally, this device would take the current gear into account.

If it already exists, I'll get my coat (Apexi comes to mind ?).

john banks

The AVC-R does do all of this. However, I have concluded that the shape of the Dawes boost curve at WOT is ideal for my turbo and the response in each gear also seems ideal. All I now need is it to be a little less hyper on part throttle. Great for a while then you realise you have to be pretty careful with the throttle on corners - thank whoever for Toyos in the wet - they let you away with murder.

This is the only reason I am so keen on TPS modulation. All I need to get what I feel now is the perfect boost behaviour is for the overall boost to be roughly scaled to the throttle position as in the original setup. I think this can easily be done.

see http://www.scoobynet.co.uk/bbs/threa...ThreadID=61077 for a welcome improvement to the boost response...