turbo boost pressure

[Anonymous]

i was talking to a mate and he said that the turbo engine has graduated boost and that it is controlled by the ecu. my car has a superchip fitted so will it still have the graduated boost or does it depend on the chip.all i know is that i is a 50bhp increase and that it ups the boost to 14.5 psi at 4500rpm. also is there a blow off vavle on them that i can play about with to get more boost also. the reason i ask is that i was in a cossie with around the same power but the kick from the turbo felt much more "pin you to the seat" - if you know what i mean!!

cheers

rodgerq

[Anonymous]

I'm doubting a 50bhp increase from 14.5 psi,
as 14.5psi is about 1 bar, not much more than standard,

the turbo engine runs at .8 bar on overboost (12psi), that is initial kick, and then it backs off to a constant .5 bar about 8psi,

Not quite sure what you mean by graduated boost, but don't just wind the boost up untill it starts detonanting as this is baad,

Have a look on Mig forums, as theres a few guys on there who have helped me out with mine,

[Anonymous]

detonating ? as in like a serious misfire with flames etc.what causes this?? whats the max boost it could cope with without changing the intercooler(which i thought would have been bigger than it is)i will get it rolling roaded soon as the more i think about it you r probably right about the power hike but i have a superchips flyer on the calibra turbo showing the power and torque curves before and after fitting. i can scan it in and show you it if you like.

[Anonymous]

Detonation is when the engine violently shakes and kangaroo's for a bit when there isn't enough fuel for the level of boost, ie, it'll be running lean at high boost,

The standard ECU detects that theres too much boost so filters it off thru an amal valve, A bleed valve is used to fool the ECU into thinking that the engine is running at a lower boost,
I'm led to believe that superchips fit bleed valves to all the 2.0 turbo's to fool the ecu into running more boost without closing it off, it should be adding more fuel to compensate though,
A small intercooler is not good either the standard intercooler on a calibra/cav turbo could only just make the quoted 204bhp, a larger intercooler could free up an instant 20bhp

[Anonymous]

Detonation is when the air/fuel emulsion explodes under high compression b4 the spark from the plugs doing it. This effectively means that the timing is fcuked up - too early(advanced). Instead of all the energy being translated into the downward stroke of the piston some is directed against the piston which is still moving up to TDC.

[Anonymous]

I was halfway there, sortoff,... this is also where the knock sensor should detecting the timings out and retarding the timing, but it doesn't

[Anonymous]

ok cheers peeps. it will be going on the rolling road soon anyway so it will be getting set up properly. it does seem to kinda do this sometimes at higher revs so i have been keeping off the throttle a bit and since its not been setup since the air filtewr fitting maybe this wont be helping things. 20bhp from a bigger intercooler not bad !!!! how much can i get one for and where from ?? easy to fit is it?

cheers

rodgerq

[Anonymous]

Intercoolers, just find 1 that'll fit somewhere and get enough hosing to connect it up, bmw tds can be made to fit and would be quite cheap secondhand, or go the full ??? and get a pace type for about ?300 upwards,

[Anonymous]

300 quid - i thought they were well more expensive !! how much extra powerwill get from that and do they come with all the hoses and mounts etc for fitting ? where can i get one from??? pace website???

cheers

rodgerq