misfire/safc
#26
I R SAD PANDA W/O BAW
Originally Posted by Aaron Cake
Damn....Partial throttle? Do you remember what map your S-AFC was on?
This is the Achilles heal with an S-AFC set up as TPS referenced. You can be under boost, yet still on your "low throttle" map.
This is the Achilles heal with an S-AFC set up as TPS referenced. You can be under boost, yet still on your "low throttle" map.
#27
I'm a boost creep...
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Originally Posted by Aaron Cake
This is the Achilles heal with an S-AFC set up as TPS referenced. You can be under boost, yet still on your "low throttle" map.
IMO the weakness of the S-AFC is not that it's too simple, it's that it's so much simpler than a full EMS that many people think they don't need professional advice or tuning to set one up.
Terrh, that's just a general comment, not aimed at you personally. Unless you think it should be...
Last edited by NZConvertible; 12-18-04 at 04:50 PM.
#28
Engine, Not Motor
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But if it's on the pressure sensor, the S-AFC will directly know the boost pressure. So it's user error if the "TPS" points are not set properly.
Problem with the S4 is the 1/4 range TPS. Can make setting up the S-AFC...interesting.
Problem with the S4 is the 1/4 range TPS. Can make setting up the S-AFC...interesting.
#29
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Originally Posted by Aaron Cake
But if it's on the pressure sensor, the S-AFC will directly know the boost pressure. So it's user error if the "TPS" points are not set properly.
Personally on a turbo I'd set the high-throttle setting at 50% (i.e. 0 psig, when boost begins). The low-throttle setting would depend on how fast your turbo spools, but I think about 40% would be about right.
Problem with the S4 is the 1/4 range TPS. Can make setting up the S-AFC...interesting.
Last edited by NZConvertible; 12-20-04 at 12:13 AM.
#30
My car was set up with the TPS.
I had low set at 98% and high set at 99%, in practice, anything over ~15% throttle was in the high throttle map...
I think it happened at EXACTLY the 3800RPM changeover, but I'm still not sure what happened.
it's definatly blown though, you can see it in the boost/vacuum gauge.
I managed to limp it home (250KM!) only cost $60 on gas... hopefully the turbo survived without damage, I haven't pulled it off yet.
How can I prevent this from happening a third time? Obviously dyno time, but will dyno time be able to fix something that happened at part throttle?
Where should I set my timing to for the new motor?
I'm probably getting an s5 jspec, maybe an s4... whatever I can get the best deal on, because I'm out of money Going to get a payday advance JUST to get this motor, so obviously I can't afford another incident.
I had low set at 98% and high set at 99%, in practice, anything over ~15% throttle was in the high throttle map...
I think it happened at EXACTLY the 3800RPM changeover, but I'm still not sure what happened.
it's definatly blown though, you can see it in the boost/vacuum gauge.
I managed to limp it home (250KM!) only cost $60 on gas... hopefully the turbo survived without damage, I haven't pulled it off yet.
How can I prevent this from happening a third time? Obviously dyno time, but will dyno time be able to fix something that happened at part throttle?
Where should I set my timing to for the new motor?
I'm probably getting an s5 jspec, maybe an s4... whatever I can get the best deal on, because I'm out of money Going to get a payday advance JUST to get this motor, so obviously I can't afford another incident.
#31
Engine, Not Motor
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NZ: Good point.
Terrh: Timing should be stock. To prevent this is a little trickier. First step is to reference the TPS from the pressure sensor, and properly dyno tune it...But you know what I'm going to say with regards to the "final" solution....standalone.
Terrh: Timing should be stock. To prevent this is a little trickier. First step is to reference the TPS from the pressure sensor, and properly dyno tune it...But you know what I'm going to say with regards to the "final" solution....standalone.
#33
eViLRotor: I dunno about that.. this engine was basically free (they practically paid me to take it away, $150 for it + the whole smashed TII it was in)
The last engine wouldn't have went if not for #@$)(* boost creep... I thought that going to an s5 turbo would cure that but obvioulsy not.. next motor gets a ported wastegate s5 turbo with a boost controller set at ~11psi
The last engine wouldn't have went if not for #@$)(* boost creep... I thought that going to an s5 turbo would cure that but obvioulsy not.. next motor gets a ported wastegate s5 turbo with a boost controller set at ~11psi
#36
Make Money.
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Originally Posted by Terrh
eViLRotor: I dunno about that.. this engine was basically free (they practically paid me to take it away, $150 for it + the whole smashed TII it was in)
The last engine wouldn't have went if not for #@$)(* boost creep... I thought that going to an s5 turbo would cure that but obvioulsy not.. next motor gets a ported wastegate s5 turbo with a boost controller set at ~11psi
The last engine wouldn't have went if not for #@$)(* boost creep... I thought that going to an s5 turbo would cure that but obvioulsy not.. next motor gets a ported wastegate s5 turbo with a boost controller set at ~11psi
#40
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Given the size of the pump and secondary injectors, and the OTT settings on the S-AFC, I don't think top-end fuelling is a problem. But you said it happened right at the secondary injector transition which may mean your primary injectors ran out of flow, or you got caught out by the brief lean condition you get at the transition when using mis-matched injectors with an S-AFC. You said you had +8% correction, but was that at all rpm/load points or just up top? What were the rest of the settings?
#42
Originally Posted by NZConvertible
Given the size of the pump and secondary injectors, and the OTT settings on the S-AFC, I don't think top-end fuelling is a problem. But you said it happened right at the secondary injector transition which may mean your primary injectors ran out of flow, or you got caught out by the brief lean condition you get at the transition when using mis-matched injectors with an S-AFC. You said you had +8% correction, but was that at all rpm/load points or just up top? What were the rest of the settings?
#43
I R SAD PANDA W/O BAW
Originally Posted by gsracer
I agree that top end fueling definitely was not a problem, if anything at only 11 pounds on the stock turbo it should be retardedly rich. I personally think it makes a lot more sense to run a pair of 720cc primaries and keep the stock 550's in the secondaries for moderate mod's on the stock turbo.