JackoliciousLegs

hmmm... i never knew that 250mmHg = 9psi?!!? Well, actually it doesn't. That's just what my stock boost gauge told me.

I hate the stock boost gauge! It's a PIECE of SH*T!!!!!! After all this time (thanks to all that helped by responding to my posts) I am in fact boosting fully! 9psi actually with cat-back exhaust! A month of hardcore worrying! DONE! Next step... intake/FCD/downpipe/cat

Thank you autometer!

Jack

NZConvertible

If the stock boost gauge only gets up to 250mmHg when you're actually boosting to 9psi (465mmHg), then your pressure sensor may be the problem. If that's the case the ECU will be receiving incorrect info, and won't think you're boosting as high as you are. Check to see the pressure sensor is within spec.

BTW, you list of proposed mods will put you dangerously close to disaster unless you replace the fuel pump AND port the wastegate first.

JackoliciousLegs

will do on the pressure sensor

JackoliciousLegs

now wait a minute... i posted this question before and everyone told me i'd be fine as long as i got a fcd!

JackoliciousLegs

oh, about the boost registering low... it also registers atmospheric pressure low, so maybe the gauge is just out of line (which i think it is)... is that still bad?

NZConvertible

If it's the gauge, no. If it's the sensor, yes.

This could be caused by the FCD. The better ones send an unmodified signal to the ECU but clamp it just before fuel cut, but some simply reduce the signal by a fixed percentage all the time, which isn't nearly as good. If yours is one of the latter ones, the boost gauge will always read low.

jreynish

iTrader: (2)

well if you are going to do your suggested mods do not boost more than 10psi without fuel pump and injectors, youwill be in dagerous territory; my suggested in the following order would be;

FCD/High Flow Fuel Pump same time;
Intake,
larger secondaries and way to tune them
DP + CAT,
that way you will most likely always be safe!

RotaryEvolution

iTrader: (30)

if you have a FCD installed i thought that tricked your ECU into thinking that the boost was lower than it actually was subsequently your gauge reading lower than your actual boost is?

is that correct or am i wrong?


edit: sorry for sounding repetitive, i noticed this point already brought up.

jreynish

iTrader: (2)

it does for the most part but the better ones only do that at the upper range of boost ie 9-10 lbs but some do it through the entier rance it 0-10, the ones that only clamp near 9-10 are the better ones, the ones that clamp the whole range aren't the better ones and can be potentially time bombs!

RotaryEvolution

iTrader: (30)

well i have always believed you should install a direct gauge anyhow. for more accurate and dependable pressure readings.

jreynish

iTrader: (2)

agreed! I don't rely on the stock guage at all!

NZConvertible

For 10psi boost larger injectors are not necessary. The fuel pump is mandatory and a fuel controller is a very good idea, but you don't need bigger injectors until injector duty cycle gets too high.

dumarjo

does any 1 have the fuel map in the ecu ?

I just curious to see !

chicoutimi