I'm playing around with the DoD on my truck. Id like it stay in 4cyl mode a bit longer. I found a few threads on here regarding upping the tps max to 20%. I made the change, but it isn't holding V4 any longer than before. Has anyone made adjustments to the vacuum tables?
AW
2017 Chevy SS Whipple
of course you ask, when i am not near my tuning computer. i upped my tps to 20% but didnt touch the vacuum table. it would seem to me, that the main problem with teh DoD issue about staying in 4cyl is that there simply isnt enough power to maintain vehicle speed with such little throttle position. you need more power at 20% throttle to maintain vehicle speed. adjusting vacuum doesnt seem like it would help because vacuum is just a means of engine load, which is limited by throttle position. my logic on tuning it, is that i need more power per the TPS to maintain 4cyl driving. i found that by adjusting my 4cyl timing table, to increase the low load driving timing table allowed for more power while not creating any KR. this has allowed me to be able to not only maintain 4cyl mode longer, but actaully accelerate slightly while in 4cyl mode. this means that i can maintain my speed on the freeway without having to switch over to 8cyl mode...DRASTICALLY INCREASING MY MILEAGE!!!!!!!!
the whole idea of DOD is to make the throttle open more and raise the engines efficiency. Remember engines are most efficient at WOT.
I count sheep in hex...
could you please elaborate a bit more?
In order for DoD to enable, the TPS has to be under the TPS Max value. Once DoD is enabled, the TPS can exceed the TPS Max.Originally Posted by AdubZ28
I change the TPS MAX to 12%. Then the Enable Vacuum table needs to be lowered. Try -10kpa to start.
Then lower the Disable Vacuum table. Logging the Manifold Vacuum will help in setting up this table.
If you lower the disable table too much, the engine will labor & vibrate since it's running on 4 cylinders under a high load.
There is a fine line between being in V4 mode under too much load & switching between V8 to V4 too easily.
Russ Kemp
btw, there is a slight naming issue with the TPS Max values that i'm fixing soon. It should read "Pedal Max" as its the pedal position, not the throttle position.
If the pedal position is exceeded DoD will disable.
Chris...
I count sheep in hex...
Great info everyone, thanks. I'll do some scanning this week
2017 Chevy SS Whipple
I started playing with the scanner last night. I would assume DOD is a status bit since its simply an On/Off value? Do I have to be connected to the truck to select a DOD status bit?
2017 Chevy SS Whipple
Exactly how much is Drastically? My truck gets 15.7mpg at 70mph with DOD disabled and on the same stretch of road gets about 18-19mpg with DOD enabled. Are you talking about more than that?
2007 GMC Sierra Z71 SLT Crew Cab 4x4 6.0L 4l70e
Modifications: True Flow Cold air Intake, HPTuned (Removed HUGE PE Delay, Added 30 to speed limiter, modified AFM/DOD for mileage increase)
Same with the pedal position in DFCO right? (Its not TPS, its pedal-position, from my observations.)
really? wow. im talking DRASTICLY more than that!!! at 70mph on a flat freeway non-DoD is around 17/18 mpg and with DoD is 24/25mpg. this is with my 07 sierra crew cab 2wd
Is that with the 5.3L or the 6.0L?
2007 GMC Sierra Z71 SLT Crew Cab 4x4 6.0L 4l70e
Modifications: True Flow Cold air Intake, HPTuned (Removed HUGE PE Delay, Added 30 to speed limiter, modified AFM/DOD for mileage increase)
So how are you logging DOD?
2017 Chevy SS Whipple
i thought DoD was only available on the 5.3
5.3 and 6.0 have DOD, 6.2 does not.
2017 Chevy SS Whipple
huh...interesting. learn something new everyday.
dont the 6.0's have the variable cam stuff? or is that the 6.2 only?
6.0s have VVT and DOD
2017 Chevy SS Whipple
WHAAAAAAAAAAAAAAAAA!!!!!!!!!!!!!!!
ok, so it IS possiable!!!!!!!!!!!!!!!!
ok, now i need to know where in the software the tuning options are and the wiring...then its off to the machine shop for my new motor
Anyone else notice that DOD and DFCO are mutually exclusive? I can not get them both to be on. If I drive in 3rd then lift, it goes into DFCO or in overdrive if I have DOD disabled. If DOD is enabled and engaged, DFCO will not. Yes, I want both to be engaged at $3.50/gal.
07 Avalanche Exhaust & CAI
I'd like to start tweaking the dod on my 6.0 truck.
What is the best way to determine when it's active in your datalog?
I wasn't able to find a status bit that shows the change, etc.
Anyone have any pointers?
Tony <---newb
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