Prodrive Sti Freeflow Cat on a WRX PPP ??? Mike Wood please !
14 May 2005, 11:59 AM
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Prodrive Sti Freeflow Cat on a WRX PPP ??? Mike Wood please !
Sorry if this has been covered before but there seems to be differing views on this. It would be great to pull them all together into one place and hopefully Mike Wood will see this and give us a definitive view..
The questions is, what would be the effect of replacing the standard downpipe and cat on a MY05 WRX PPP with the sports cat supplied with the Sti PPP ? ie not a full decat...
More Power / Torque / response ?
Any issues with predet or overboosting ?
Remap required/preferred/not needed ?
Also I seem to remember Mike saying that 265 is the max safe power for the injectors on the WRX - can someone please confirm / clarify..
Many Thanks guys..
The questions is, what would be the effect of replacing the standard downpipe and cat on a MY05 WRX PPP with the sports cat supplied with the Sti PPP ? ie not a full decat...
More Power / Torque / response ?
Any issues with predet or overboosting ?
Remap required/preferred/not needed ?
Also I seem to remember Mike saying that 265 is the max safe power for the injectors on the WRX - can someone please confirm / clarify..
Many Thanks guys..
14 May 2005, 12:37 PM
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Forget me - the search facility is a wonderfull thing..
http://bbs.scoobynet.co.uk/showthrea...=injectors+wrx
http://bbs.scoobynet.co.uk/showthrea...=injectors+wrx
14 May 2005, 01:37 PM
#3
I've still got a couple of them hanging around in the attic - I won't fit it till it is remap time.
Ive sold a few prodrive d/pipes over the last year, but I believe they went on std WRXs without problems.
Seem to remember Jim Theo putting one on a PPP WRX with an STi IC and had high (105%) injector duties that went on for a bit too long for safety?
NIck
Ive sold a few prodrive d/pipes over the last year, but I believe they went on std WRXs without problems.
Seem to remember Jim Theo putting one on a PPP WRX with an STi IC and had high (105%) injector duties that went on for a bit too long for safety?
NIck
14 May 2005, 08:30 PM
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Update here...!
USDM factory fuel pump in place of my original WRX pump and IDC went more or less about 100%!
Strange ah?
I do believe the same but I don't care why it happens, what is more important is that currently my car has minimal knock correction in the area between 5300-5700 where all new age WRXs suffer badly from ignition retardation (reduced advance).
I'd like also to inform you that currently I have Scoobysport decated downpipe (no cats at all), factory center, STI factory back box and AVO turbo hose.
The ECU works perfectly at least with our 100RON fuel and according to DD logs and my knocklink there isn't any problem.
Probably this isn't "good" advice but Prodrive has wide safety limits in his remap, bear in mind this is for newest Prodrive ECU remaps after 6/2003 if my memory serves me right!
JIM
USDM factory fuel pump in place of my original WRX pump and IDC went more or less about 100%!
Strange ah?
I do believe the same but I don't care why it happens, what is more important is that currently my car has minimal knock correction in the area between 5300-5700 where all new age WRXs suffer badly from ignition retardation (reduced advance).
I'd like also to inform you that currently I have Scoobysport decated downpipe (no cats at all), factory center, STI factory back box and AVO turbo hose.
The ECU works perfectly at least with our 100RON fuel and according to DD logs and my knocklink there isn't any problem.
Probably this isn't "good" advice but Prodrive has wide safety limits in his remap, bear in mind this is for newest Prodrive ECU remaps after 6/2003 if my memory serves me right!
JIM
18 May 2005, 11:40 AM
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Bartop
In simplistic terms, fitting the downpipe from an STi PPP may not be such a good idea, not least because the later ones may not even fit at all.
The WRX performance package is basically limited by injector duty and is tuned in a way that it always leaves a small amount of spare capacity so that it would make a difference if the ECU decided it needed to use the high-det map. Further mods to allow the engine to flow more air and therefore give more power (I assume that this would be the aim!) would need more fuel which the injectors are not able to provide safely. The only way this could be done is to lean the fuelling off but this pushes up exhaust gas temperatures and the ECU pulls ignition timing as the onset of detonation is earlier. Boost control will also need to be looked at as you will find it overshoots quite easily.
In summary, changing the exhuast to make it flow more will effectively lean the mixture as the injectors will struggle to provide the fuel that the ECU is asking for. The net result may well be more power but this may be matched by a disproportionate reduction in potential engine safety.
Having said all of the above, it doesn't mean we wouldn't offer something in the future if we can make sure it's safe.
Mike
In simplistic terms, fitting the downpipe from an STi PPP may not be such a good idea, not least because the later ones may not even fit at all.
The WRX performance package is basically limited by injector duty and is tuned in a way that it always leaves a small amount of spare capacity so that it would make a difference if the ECU decided it needed to use the high-det map. Further mods to allow the engine to flow more air and therefore give more power (I assume that this would be the aim!) would need more fuel which the injectors are not able to provide safely. The only way this could be done is to lean the fuelling off but this pushes up exhaust gas temperatures and the ECU pulls ignition timing as the onset of detonation is earlier. Boost control will also need to be looked at as you will find it overshoots quite easily.
In summary, changing the exhuast to make it flow more will effectively lean the mixture as the injectors will struggle to provide the fuel that the ECU is asking for. The net result may well be more power but this may be matched by a disproportionate reduction in potential engine safety.
Having said all of the above, it doesn't mean we wouldn't offer something in the future if we can make sure it's safe.
Mike
19 May 2005, 12:03 PM
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The last downpipe from Prodrive is bellmouth with splitter type while the olders where twin exit.
JIM
PS: Forgot to mention we have 100RON fuel that minimizes the possibility of det and helps probably in lower IDCs and EGTs
JIM
PS: Forgot to mention we have 100RON fuel that minimizes the possibility of det and helps probably in lower IDCs and EGTs
