Any gains will depend on how bad the OEM setup is. Toyota usually does a pretty good job, so it will be interesting to see what they come up with.
MAF-CI
I was on scion evolution and I read that there is a tC owner that droped his car off at C.P.E for a proto type. They build a maf/cai upgrade for a couple of cars. They just did one on a mazda 6 with hp gains of 22.67 overstock and torque gains of 21.54 overstock. I hope it all works out fine for the tC.
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You can look them up at cp-e.com. Yes, it will.
wow, that's quite a lot of gains for a CAI...so they added a cai and tweaked the air to fuel ratio?
Sort of. They are recurving the MAF, so the ECM thinks more (or maybe less) air is getting in. I'm not sure how this will work with a Toyota since TCCS uses feedback from the O2 sensor to provide an error correction factor. They have both long term and short term corrections, so unless they remap the MAF to something greater than 20% off, TCCS will just apply a correction to the a/f ratio to bring it back to the desired value.
This is one of the things that makes tuning Toyco ECMs with piggybacks very challenging. If you make adjustments to fuel in the closed loop maps, it just corrects to stoichiometric and applies the correction factor to all maps including the open loop maps, so there is no net gain. The trick it to apply changes so they only affect open loop maps (that's the only place you're going to see a gain anyway). Many Toyota tuners have complained about the ECM doing this because it forces them to be smarter than the ECM. Not a simple task.
One of the tricks is to adjust so the standard closed loop maps appear lean to the O2 sensor, which applies a rich correction to open loop. It's just tricky to get it right for best power.
This is one of the things that makes tuning Toyco ECMs with piggybacks very challenging. If you make adjustments to fuel in the closed loop maps, it just corrects to stoichiometric and applies the correction factor to all maps including the open loop maps, so there is no net gain. The trick it to apply changes so they only affect open loop maps (that's the only place you're going to see a gain anyway). Many Toyota tuners have complained about the ECM doing this because it forces them to be smarter than the ECM. Not a simple task.
One of the tricks is to adjust so the standard closed loop maps appear lean to the O2 sensor, which applies a rich correction to open loop. It's just tricky to get it right for best power.
You can say that again, Lance. I tried to fool the ECU with a SplitSecond's additional injector controller to lean out the A/F on Matrix' SC - after 2 hours of dynoing / fixing the maps for the injector we ended up with 5hp that disappeared after another couple of runs. ECU was smarter than us...
that site makes no sense to me
You are insane, Pliss.Originally posted by Plissken@Mar 13 2005, 01:37 PM
All your engine belong to ECU.
In case you don't get it.
Edit: Changed the link.
well, since you're changing the a/f ratio to thinking that it's getting more air, wouldn't that have a negative effect on your mpg, since you'd be running rich?
You would think so, but the tC has a wideband planar O2 sensor in the header, so any attempt to run rich in closed loop will be quickly squashed by the ECM.
whats the time frame on this piece? is this something that's gonna be available soon or are we talking about a aem intake type wait?
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