Project RS

[ScottyB]

All the 14.7 is closed loop mode, (ps if you wanted to pick back up gas mileage, you could lean burn your closed loop mode), as you can see as "load" increases there is a certain point where it drops out of closed loop mode. Same with this rpms. Now you look at highway, and depending on how fast he is going, and wether it is a hill or descent or smooth will increase or decrease load. He has now changed the parameters for when the car enters closed loop mode, now it is open loop for "more time" and the possibklity of being in open loop during "highway cruise loads". Thats why he will be seeing a decrease in gas mileage.

this is pretty much right on. there is a "closed loop delay" value in subaru ECU's in which at any point the ECU recognizes that it's time to switch to open loop, the computer instead starts a timer. this is to retain gas mileage during small periods of increased throttle, and it's played havoc with the subaru turbo cars especially. my delay is now zeroed, so anything more than a slight change in throttle will cause an immediate jump to the richer open map - which is what i want. of course throttle change is only part of it - also factoring in calculated load as mentioned. going up a hill at 70 mph for instance, i will definitely be in OL. before, the car would resist moving to OL and then when it would, the OL values would be no different than the CL values....and if i wasn't on 93 in the debt of winter, there was quite a bit of detonation until passing 4k rpm or so.

there is a happy medium that is still to be found. i may bring in a little closed loop delay just for MPG sake or i might lean out the closed loop or low-load OL values. however, that is more advanced than where i'm at, and i don't have the proper equipment yet to really do a complete tune.

Proven wrong, mythbusters did a thing about wether you should have the pickup gate closed or open and I think it was a 1.5% difference. Not anything any of us would notice. Now...a camper shelll may be different.

fun fact: the optimal orientation is a half open/half closed tonneau cover as seen below on the old syclone land speed truck. the open part is in the front. i always thought that was really weird.



back on topic....