Decel Enrichments?
Thread Starter
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Is there anything to cut fuel faster when I lift? I go pretty rich when I lift the throttle before over run kicks in, and by pretty rich I mean fatter than 11:1 in most cases. I've tried reducing the decel % under acceleration wizard but it would cut fuel too violently if i was just lifting the pedal a little while cruising. It's not a big deal, but if I could solve it, it'd be cool.
Thread Starter
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
when I run it through MLV, it's always wants to pull fuel at my entire <100kPa 3000rpm column cause I always shift there. Otherwise I could probably pull a bunch from the lower cells themselves...
Thread Starter
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
I used to let it do it's thing, i had a few cells that were lower than where I idle at. Then I had to cruise on the highway at 3000RPM, didn't work out so well. So I usually shift when I'm in boost, the entire column was way too lean out of boost. But get what your getting at.
I was wondering the same thing. You can lean it enough with decel set to like 60% but the problem is when cruising or in boost, if it senses decel because your foot moved on the pedal, it cuts fuel as well and that's not good. I don't know what can be used to detect real decel and just noise or slight falling change in tps signal.
The thing is you can be at 120 kpa and lift of the throttle to slow down or shift or it could be just noise or slight movement of your foot but MS can't make a difference and does the same in both cases.
The thing is you can be at 120 kpa and lift of the throttle to slow down or shift or it could be just noise or slight movement of your foot but MS can't make a difference and does the same in both cases.
Thread Starter
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
I dropped my bottom row of my fuel table down to 15% from 40% and my spark table 17° across. Made no real difference. I moved the over run to trigger after .1s but it's still a touch too slow, IIRC I'm already at 80% decel enrichment, any more and it would trigger during normal driving.
I'm pretty sure this is why my stock cat has **** rattling around inside it. Happened at my last autox. I'm pretty sure i was dumping lots of fuel in there and melted it down on the inside. I bet i'd shoot flames like split does if I had a straight through exhaust.
In for solution.
In for solution.
Thread Starter
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
I have no cat, dont shoot flames. it doesn't happen for that long, but i don't like seeing it hover at 12:1-11:1 for no reason before overrun. I watch the fuel cells and I completely removed fuel from that area but it didn't do anything.
Nice explanation from msextra.com:
Greets
If you are running WOT, then the injectors are dumping a heap of fuel into the engine.Just because you take your foot off the pedal doesn't mean that fuel disappears, even if the injectors stop right then.As the amount of air is also greatly reduced it has to go rich till the feul cloud is spent.The dip will exist but you may be able to reduce its duration. This is why as revs increase there is no advantage to sequential injection over batch.The injectors are firing when the valves are shut due to engine demand.
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