DFCO question
Thread Starter
Instructor
Joined: Jul 2017
Posts: 219
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From: Long Island NY
DFCO question
Does anything here mess around with tuning? I have been messing around with my 95 via Tunercat to get more engine braking, but haven't quite got it where I want. Looking for suggestions. Thanks!
Last edited by Ranger72; Feb 21, 2023 at 10:58 PM.
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Probably an obscure question. Back in 2010, I looked at this. It's been a long time ago but I'm thinking I decided to leave it alone. If your 95 idle is controlled with an IAC, there may/may not be an issue running it above idle RPM w/o fuel supply. Put another way, letting the ECM control idle and fuel (without robbing it of fuel) didn't accomplish much (MPG) and, in turn, didn't warrant a big enough reason to change what GM intended.....possibly with sudden stop/accel back-to-back? Though I also thought there were good reasons to use it. After all, why put it in there as a manageable parm?
IIRC, it might also be I abandoned it because my new 383 engine had zero popping -- much better than stock. This (and other reasons) led me to believe fuel control was coded reasonable close. (He says KNOWING it's a bit rich...LOL)
Google DFCO (decel fuel cut off). If you don't find advice that way (or here), try on 3rd gen too.
Quick search, I like the initial flavor of this thread....
https://forum.hptuners.com/showthrea...4-What-is-DFCO
GL!!!
IIRC, it might also be I abandoned it because my new 383 engine had zero popping -- much better than stock. This (and other reasons) led me to believe fuel control was coded reasonable close. (He says KNOWING it's a bit rich...LOL)
Google DFCO (decel fuel cut off). If you don't find advice that way (or here), try on 3rd gen too.
Quick search, I like the initial flavor of this thread....
https://forum.hptuners.com/showthrea...4-What-is-DFCO
GL!!!
Last edited by GREGGPENN; Feb 24, 2023 at 04:28 AM.
Race Director
Joined: Jun 2004
Posts: 13,956
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From: WI
I used tuner cat too but didn't change dfco. I do remember turning it off to see what coasting was like. A thought would be to enable it higher speed but that may cause more issues that it's worth.
Melting Slicks
Joined: Aug 2003
Posts: 3,394
Likes: 393
From: Lakeville MI
Engine braking is mostly due to throttling. You can close the IAC faster (increase the throttle following slope/gain) and reduce the min throttle opening so that it will barely idle. DFCO does help a bit, but it is only a minor influence.
