leeps

When i got my car the dealers said they set the boost to standard (0.9 bar) but my gauge (which is a reliable one) said only 0.8 0r 0.7, when i took it off the gauge then went up to 0.9 bar ...
So my question is, how does the ecu get its max boost reading. If the manual boost controll is fooling the wastegate, does it fool the ecu as well.So could it be that the dealers set the ecu to 0.9 bar but the manual boost controller was only set to 0.8 or 0.7 ???
Any thoughts

ScoobyDuck

iTrader: (1)

not sure what you mean

you have a boost gauge (they're not all 100% accurate! but it's the difference your concerned about!)
you are running a manual boost controller (e.g. dawes, ebc etc)

when you drive normally, you only get 0.7-0.8Bar

when you remove the manual boost controller (HOW ? re-plumb the factory solenoid?) you get 0.9 ( which is standard) again ?

i suspect the manual boost controller had been put on to stop the car from spiking / fuel cutting, or to raise the boost.
if the garage left it on they probably just adjusted it to ABOUT 0.9 and that was that. but normally they'd get rid of it - unless a problem like above was present.

if it's adjustable, adjust it a bit till you get 0.9 & take it for a drive and make sure you dont get any spikes etc & leave it at that.
or - put it back to factory & do the same checks. you'll probably get bigger spikes!!

the ECU will try to control the boost if it's plumbed in. other than that, it just monitors the boost & adjust the ignition & fuel according to what it sees (up to a point! i.e. dont raise it unless you monitor the AFR's & check for knock!)

hope that helps...
Steve

[Edited by ScoobyDuck - 8/27/2003 5:18:07 PM]

leeps

well steve ur right, with the manual boost controll off (atomic GFB) i do have problems with boost spike, so thats why i gotta put it back on. When i asked the GFB website, the guy there said that if i raise it to 1 bar, the car's ecu should still be able to detect kncking and retard the timing if necessary. Also the my98 cars do run rich ... Is it really necessary for just a 0.1 bar increase ... ??

ScoobyDuck

iTrader: (1)

no - in theory, it should be ok. I have a mate who has raised his boost to 18psi (1.24Bar) and his is still REALLY rich! & gets no knock either.
not saying that's not gona be the same on yours, but it should be ok just increasing that little bit.

if you are really worried, go back to the garage & get them to go out with you with a select monitor (plugs into the ECU) and get them to check the air/fuel ratio & if the ecu is seing any knock correction in the ignition.

good luck!
Steve

jonmyers

Depending on the car model you may reach fuel cut around 1.0 to 1.1 bar unless this has been raised.

I wound my dawes up until I just got fuel cut (high gear high revs needed to thoroughly check), then wound it back a half turn. That was about 15 psi in my MY99 before remap. Makes for a quicker car!

Jon

ScoobyDuck

iTrader: (1)

never hit fuel cut in mine ! even with is herendous boost control !
or when I've been mucking around recently with modifying the boost control to make it better (3-port etc) and been hitting 19psi !

my97 btw

but you're right .. earlier cars do hit significantly lower!
think 99/00 cars hit a bit lower too.. like 17.x psi

Steve



[Edited by ScoobyDuck - 8/29/2003 12:19:23 AM]

leeps

Hey steve

Just wondering what kind of boost controll are u running?
In your opinion is an EBC really worth the money and which
one would u get ?? Cos i been thinking about the blitz sbc id,
thinking that an EBC would make life easier than constantly
tinkering and then checking the boost gauge each time? On the other
hand a mate of mine says that unless im considering more modification (K&N replacement filter, free flow exhaust system 56mm, upgraded dump valves recirc, intercooler waterspray at the moment), im not really going to boost above 1.1 bar anyway. Is it fair to say that an EBC would only be really appreciated with a fuel management system. Even then how high can u really boost the car reliably ???

Edwin