Fuel Cut on RPM decrease

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FastButBlind
Posts: 28
Joined: Sat Jan 02, 2010 4:46 am

Fuel Cut on RPM decrease

Post by FastButBlind »

Hi,
I was tuning a BMW with 173 ECU, and noticed that the car get a bit weak during shifting, I wonder if I can tune the fuel cut on RPM decrease, so i can hold the RPM up high during the shifting, this can be done easily in standalone ECUs, but can it be done using tunerpro, and ostrich?
revlimit
Posts: 202
Joined: Thu Mar 19, 2009 6:41 pm

Post by revlimit »

I think I included this in my latest XDF for 173, deceleration fuel cut, but this is just fuel saving feature, I don't think you can fix it by adjusting this. When shifting simply do not let the gas all the way back, keep the throttle a little open when shifting
FastButBlind
Posts: 28
Joined: Sat Jan 02, 2010 4:46 am

Post by FastButBlind »

I can't see deceleration fuel cut, Sorry, what XDF you are talking about?
revlimit
Posts: 202
Joined: Thu Mar 19, 2009 6:41 pm

Post by revlimit »

Maybe I did not include it, but that won't help you.
FastButBlind
Posts: 28
Joined: Sat Jan 02, 2010 4:46 am

Post by FastButBlind »

sure it wont make a major difference, but it kinda give a good shift, will check other way to improve that.
Thanks
DmcL
Posts: 73
Joined: Wed Dec 08, 2010 11:55 am
Location: Northern Ireland
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Post by DmcL »

i think i found a decel fuel map, have not fully checked/confirmed it tho and its very possible the map is for god knows what else tho.

from what is already known about the 173 u can adjust the closed loop idle speed 6x6 map to help keep the revs from dropping too quickly on the higher RPM end of the map. also by adjusting this map instead of the one i mentioned above (which i think is an unknown map in current 173 XDF files on the net) u dont risk messing up deceleration characteristics of the engine when the car is in gear, too much and the rear wheels may lock easier at high rev lift off, too much and engine braking would suck.

personally tho i prefer the revs to drop faster on gearchange, im a bit biased there tho because ive got a Z3 M coupe stick in the car so i have no problems getting out of one gear and into the next quickly.
EthosMotorsports
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