fiestaturbo.com

[EvilFranky]

Hello lads...

Does it make much difference to the fuel consumption if u have selectable boost from inside the car? Say 7psi low boost and 14psi high boost?

Or am i just stating the obvious...cos i think thats something i'm gonna have to think about going in for...bloody fuel bills

[Fezzy Turbo]

Franky........dont do it. Adjustable boost is dodgy unless you fork out for the proper Jap stuff and air injectors....££££££

The usual adjustable boost is just a bleedvalve inside the car, but you can not adjust your fuelling. You can only have it set for either 14psi or 7psi.....so you will either over fuel or run too lean.

Best to comprimise and get your car set-up at say 10psi.

cheers

[Muzza]

I thought that switchable boost was done by a switch taking out the amal valve and cutting in the chip.
There was an article in fast ford a few months back if thats any help

[Asad]

Can i just ask.... is'nt the fuel pressure controlled by pressure in the manifold? Or at least related to it?

Or is the fuel pressure set at a pre determined level by the chip?

Reason i ask is [ERRR] on my old turbo (not fezz), the fuel pressure was controlled by way of the pressure in the manifold. It was set to be 3-4 psi above boost pressure. So at 6psi, the fuel pressure 9-10 psi. This meant that when i increased the boost, i did not have to worry bout fueling.

Doesnt the same principle apply here?


Asad

[EvilFranky]

nutsack to 10psi! LOL, i wanna keep my full 167 horses!

Wasn't sure how it worked...bugger, guess high fuel bills are just the norm from now on then

Its gonna get worse when i put me CAM in aswell!

[Fezzy Turbo]

The chip only controls when and how long the injectors are on, but it is the fuel pressure determines how much fuel gets through the injectors at the times they are on.

The injectors may fire, but if there is not enough fuel in the fuel rail they will run lean...........then it's BANG!!!! But if there is too much fuel there it will flood through and over fuel.....then bore wash.

That is why it is sssssssssoooooooooo important to get the fuelling set-up on a RR so it can be monitored and set for idle......through the rev range and under load.

cheers

[Joris]

But if you switch low boost on,
the map sensor will tell the car it is running less boost,
and so won't overfuel ?

This is a question, not a statement, lol.