What I have learned from my DashHawk

[oldschool]

I was excited to recently be one of the first to test/try the instantaneous MPG function to the already long list of things a DashHawk can now do.


Current screen setup at the moment is the following"

ECT Temp Trans Temp

Current Gear MDS Status

Current MPG Absolute Load


Here is what I learned.

1) MDS does funny things to a motor when it engages and disengages. It puts a bit of extra load on the motor when it comes in and out that I normally wouldn't have thought twice about.


2) MDS isn't the amazing fuel saver you would think but it helps. So much has to do with current gear and Abs. load that you wouldn't typically imagine. A WOT run can get about the same MPG at times as sitting in 4th or 5th going up a hill without upshifting. Try it...I kid you not.

3) Our cars can get 100+mpg in most situations coasting either down a hill or to a stop sign/stop light. This is temporary of course but heck the motor can do alot of things we wouldn't normally think about and it is possible to maximize MPG without driving like a grandma.

4) Just because you are cruising at a low gear on the highway doesn't mean you are getting 25+mpg. Watching the relationship between load/current gear/rpms and TPS are the most important factors.

5) Giving the car even sometimes light gas in a low gear is more load on the motor and decreases MPG more then I originally thought.

6)Dumping codes (like my low ECT temp code from my 180 stat) are easy to ditch when you take too long to warmup to 180 on a cold day.

7) MSD rocks for online customer service...plus alot of members here (KGB, Matt R. and a bunch of others) post regularly from this forum so you can see how things work/don't work almost in real time.

oldschool

[RobAGD]

Yea I have been playing with the MGP stuff as well.... Man I was expecting better numbers while in MDS at highway speeds :/ Woof

-R

[mhigham]

#1 - The throttle opens more with MDS on to reduce pumping losses. I notice mine comes on at 15.5inHg and the throttle goes to about 6inHg.

#3 - On decel above certain RPM, the engine will be in fuel-cut. No fuel being used at all.

#7 - Yes, you are right. Their customer service rocks. Superchips could learn a LOT from their brothers.

Mike

[Tweaks]

Maybe you guys could tell me... Does MDS have a cutoff speed? i was told on my test drive that it only works below 100kph. And at the time i thought, "well whatever"... but now i realize I CANT DRIVE THAT SLOW. So anyways, i dont put any faith in what a salesman tells me, but i do know i get awesome gas mileage on smaller 2 lane roads going 95kph... like 29mpg for reasonably flat trips. yet i only get ~23-4mpg on the highway at 110kph+. So that started me really thinking that maybe there was some truth to what he was saying. I personally notice a bigger difference in MPG between 95 and 110, than i do between 110 and 125, so it seems like something may actually be going on there. Air resistance does ramp up exponentially, but that would seem to mean it should continue to make a bigger difference up around 125. I'm just scratching my head here and wondering whats going on.
Normally i just run 125-135 and dont really care what the mileage is, but when i get someone wanting to rag on the magnum and call it a gashog, i like to be able to tell em what she can really do. And i dont really see why MDS would be disabled at any speed, since i think its fast enough and smart enough to switch off when you want/need full power. If it is getting disabled i want to be able to mod the speed its set at to something higher!

PS. I know i mixed metric and imperial thru there, but i came from the states and the gas mileage is the hardest thing to get used to, since its completely flipped upside down and with a drastic difference between a liter and a gallon. Just doesnt make sense to my current brain programming.

[oldschool]

I don't know about the km translation but I have noticed MDS from 15 mph through 85 mph but I wasn't thinking of looking for it so it may work on a wider range. Since so much has to do with load, I think pushing the car through the air with that kind of drag has to cause MDS to get a little less likely to kick in since the engine load may be too great.

oldschool

[RobAGD]

Also as you add HP, the threshold goes up as well.

-R

[lafrad]

In my observed opinions: MDS will run so long as RPM, MAP pressure, and Oil pressure parameters are met... Speed doesn't have anything to do with it.... same with calculated load (altho calculated load is based off of MAP pressure somewhere, so it can appear to be related)

MDS will stay active even through shifts on the transmission if you have the extra power.

[mhigham]

In my observed opinions: MDS will run so long as RPM, MAP pressure, and Oil pressure parameters are met... Speed doesn't have anything to do with it.... same with calculated load (altho calculated load is based off of MAP pressure somewhere, so it can appear to be related)

MDS will stay active even through shifts on the transmission if you have the extra power.

Yep, as long as mine hits the 15.5 inHg vac, MDS will come on regardless of speed. At 3.5inHg it kicks out, which is enough to push me past 90MPH.

I have recently turned it off and have noticed no change even though I spent a long time in MDS. I will give it a couple more tanks to be sure. I keep all receipts and calculate it, so I have a good reference.

Mike

[MattRobertson]

Rob, do you think MPG analysis will work on a heavily modified motor like mine?

When did this update come out, guys?

[RobAGD]

This is the new beta Matt.

I think it should work if the mappings are right for the injectors. That would be a question for Ken to answer.

-R

[Mr. iNCREDIBLE]

I've had an MDS light on the car since a month or so after buying it...

when Diablo came out and the option to turn off MDS was made available I did just that..

in over 6 weeks now I have had NO MDS on the car and my MPG is the same...

I have been steady at 14.1 MPG since I bought the car, only bumping up to 18 or so on a couple trips to Las Vegas (250 miles from my home)....

MDS is worthless IMO especially if you have CAI and or Exhaust. I never cared for it and the minute I crack the motor after the warranty is up it is completely GONE...

[oldschool]

I have been using the beta for maybe 2 weeks now, maybe a little less. It is really spot on and updates rapidly.

[oldschool]

I've had an MDS light on the car since a month or so after buying it...

when Diablo came out and the option to turn off MDS was made available I did just that..

in over 6 weeks now I have had NO MDS on the car and my MPG is the same...

I have been steady at 14.1 MPG since I bought the car, only bumping up to 18 or so on a couple trips to Las Vegas (250 miles from my home)....

MDS is worthless IMO especially if you have CAI and or Exhaust. I never cared for it and the minute I crack the motor after the warranty is up it is completely GONE...

If it can't hurt how bad could it be? Giving the chambers a little break when they aren't needed can't be a bad thing for cruising right?m Around town won't make a bit of differnce for the MDS since it would engage/disengage so frequently no real gains can be seen. Only on frequent "cruising" trips for a somewhat extended time would show any real measureable gains. If you can get your hands on a borrowed dashhawk or something you would see beyond a simple MDS light when it is working to make more MPG's and when it is not. Without seeing in real time what it does it will be useless to you to have it unless you know how to maximize when it happens.

[oldschool]

Matt, give it a shot...when I am looking to save a little the measurements have given me at least, alot of info when you watch the PID's I am.

[done]

I've had an MDS light on the car since a month or so after buying it...

when Diablo came out and the option to turn off MDS was made available I did just that..

in over 6 weeks now I have had NO MDS on the car and my MPG is the same...

I have been steady at 14.1 MPG since I bought the car, only bumping up to 18 or so on a couple trips to Las Vegas (250 miles from my home)....

MDS is worthless IMO especially if you have CAI and or Exhaust. I never cared for it and the minute I crack the motor after the warranty is up it is completely GONE...

Clearly either your MDS has never worked or you have not ever allowed it to work. That is about the lousiest gas milage I have seen reported by a reliable source. Your experience is not the standard.

MDS does work and there is no rational reason to disable it. I don't consider the "sound" issue to be rational, by the way.