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What cam do you have?
Wondering if it's really even worth it for you to advance.
Honestly not even sure. PO told me it was 'competition cam' (hence the signature entry) and it definitely isn't stock, but it is mild. I wouldn't be shocked if it was a WebCam or something. It idles really well and favors 3500-5500. On my next belt change I want to pull it and maybe take measurements.
New idea for expanding functionality - adding a programmable shift light. My car either didn't come with the factory shift light, or it's just always been broken. I can see the area it's supposed to be, but I've never seen it come on.
So I was thinking, it would be really easy to add a configurable shift light. I was reading that a stock 944 has it tailored for economy - the DME sends a signal to the economy gauge based on injector duty cycle and there's some sort of IC that uses RPM, road speed, and that signal to calculate everything.
So I got to thinking, I could use one of the MS spare outputs to just turn on an LED up there under certain conditions. It's the same principle as how I used MS to drive the cooling fans - you tell it under which condition(s) to active/deactivate a pin, and it will do it.
For the fans I chose coolant temp but for the shift light, I'll use RPM and MAP reading. For those unfamiliar with MAP readings, it's just the manifold vacuum. As load on the engine increases, the MAP reading will become closer to atmosphere. I decided to set the light to activate when RPM > 4000, and when MAP < 85. (that's in kPa).
You also have the option to do "or" along with "and" for certain situations, and there are dozens of variable to choose from. Basic sensor readings, in addition to calculated variables like the time-rate of change of TPS or MAP signals and so much more.
This way, the shift light comes on at 4000 rpm (subject to change) unless the MAP values are relatively high (I chose 85 kPa as a starting point and will change as needed). Another strategy I may try is to have it monitor MAPdot instead of MAP. The former is the first time derivative of the MAP reading. So if MS sees that MAP values are getting high pretty quickly (i.e. driving it more briskly than usual) it will alter the time at which the shift light comes on.
As for actual wiring, it's really easy. Assuming the LED is in place, you just connect the ground terminal/wire of the LED to the MS output, ALED in my case. Then you give it keyed +12v on the other side, through a 10 kohm resistor so it doesn't burn out immediately. Boom, programmable shift light.
Car has been daily driven for the most part, pleased to report ZERO issues and PROPS to B&G for a good product. The tune is pretty dialed in, and there is still development being done....
Car has been daily driven for the most part, pleased to report ZERO issues and PROPS to B&G for a good product. The tune is pretty dialed in, and there is still development being done....
I'm so tempted to do this to my 951! But the same as you, mine is a daily driver. It can't be down for too long.
Thank you for posting your experience with MS. I just read the whole thread.
You mentioned wanting to get on a dyno for a final tuning. Has that happened?
No, mainly because I'm still making changes to the car which would require retuning. Last month I threw in a 3 bar FPR and I have recently been playing with E85 with a GM Flex Fuel sensor. I was going to update this thread with that soon, actually. As it sits the tune is actually pretty good and I don't think a dyno tune is really warranted. But I do want to get it on the dyno soon, just to see what power it's making over stock. I drove a stock 951 last week and this car is way quicker than the 951 when it's not in boost. So much more usable torque down low.
No, mainly because I'm still making changes to the car which would require retuning. Last month I threw in a 3 bar FPR and I have recently been playing with E85 with a GM Flex Fuel sensor. I was going to update this thread with that soon, actually. As it sits the tune is actually pretty good and I don't think a dyno tune is really warranted. But I do want to get it on the dyno soon, just to see what power it's making over stock. I drove a stock 951 last week and this car is way quicker than the 951 when it's not in boost. So much more usable torque down low.
Come up and see me March 5th and we can hit the dyno together. $50/3 runs
New idea for expanding functionality - adding a programmable shift light. My car either didn't come with the factory shift light, or it's just always been broken. I can see the area it's supposed to be, but I've never seen it come on.
So I was thinking, it would be really easy to add a configurable shift light. I was reading that a stock 944 has it tailored for economy - the DME sends a signal to the economy gauge based on injector duty cycle and there's some sort of IC that uses RPM, road speed, and that signal to calculate everything.
So I got to thinking, I could use one of the MS spare outputs to just turn on an LED up there under certain conditions. It's the same principle as how I used MS to drive the cooling fans - you tell it under which condition(s) to active/deactivate a pin, and it will do it.
For the fans I chose coolant temp but for the shift light, I'll use RPM and MAP reading. For those unfamiliar with MAP readings, it's just the manifold vacuum. As load on the engine increases, the MAP reading will become closer to atmosphere. I decided to set the light to activate when RPM > 4000, and when MAP < 85. (that's in kPa).
You also have the option to do "or" along with "and" for certain situations, and there are dozens of variable to choose from. Basic sensor readings, in addition to calculated variables like the time-rate of change of TPS or MAP signals and so much more.
This way, the shift light comes on at 4000 rpm (subject to change) unless the MAP values are relatively high (I chose 85 kPa as a starting point and will change as needed). Another strategy I may try is to have it monitor MAPdot instead of MAP. The former is the first time derivative of the MAP reading. So if MS sees that MAP values are getting high pretty quickly (i.e. driving it more briskly than usual) it will alter the time at which the shift light comes on.
As for actual wiring, it's really easy. Assuming the LED is in place, you just connect the ground terminal/wire of the LED to the MS output, ALED in my case. Then you give it keyed +12v on the other side, through a 10 kohm resistor so it doesn't burn out immediately. Boom, programmable shift light.
Did you figure out how to make the Fuel economy gauge functional again with MS??
Yes - but I never implemented it because it would never be accurate with the injectors I'm running. All you would need to do is branch one of the injector signals into the yellow/black wire that goes into the tach. On the early NA this is under the steering column. The IC in the cluster "expects" the signal to represent a stock-sized injector, but since mine are bigger, the pulse width represents a higher amount of fuel...so it wouldn't be accurate.
Are you running stock injectors? If so, it should work like stock after making that connection.
No I'm not.. I'm using 4 Bosch 0280155868 inj, flows 375 cc/min at a tested pressure of 3 bar, or 36 lbs/hr at 43.5 psi. is there a pin on the DME connector that goes to it I found the male half of the DME online so I am using it as my interface so I don't have to cut into the stock wiring. I though that since I'm using larger inj it would have a shorter pulse width? but main reason is just for functionality of gauge seems to just bounce all over the place now...
Another question i have after reading another one of your post you say the stock inj actually flow is 22 lbs because the stock FPR is not set to 3 bar so how would i cal what these inj are actually flowing right now also inj dead time I have the value for Latency (dead time)@ 12volts=0.621 ms@ 14volts=0.391 ms. MS II asks for V at 13v?? right I have it set around 510 ms.
Trying to tune for cold weather 30 deg n below...
DAS944 You mentioned wanting to get on a dyno for a final tuning. Has that happened?
No, mainly because I'm still making changes to the car which would require retuning. Last month I threw in a 3 bar FPR and I have recently been playing with E85 with a GM Flex Fuel sensor. I was going to update this thread with that soon, actually. As it sits the tune is actually pretty good and I don't think a dyno tune is really warranted. But I do want to get it on the dyno soon, just to see what power it's making over stock. I drove a stock 951 last week and this car is way quicker than the 951 when it's not in boost. So much more usable torque down low.
Surely a Dyno Session would greatly assist the tune? or does the MS software allow you to record and change parameters in real time road driving ?
Why RPM did the 951 come on boost? I'm keen to try a stock 951 or 3.0 S2 as a comparison, I did try a friend's 3.8 Gen 2 997 at the weekend and he drove the 924S that was an interesting comparison for both of us!
No I'm not.. I'm using 4 Bosch 0280155868 inj, flows 375 cc/min at a tested pressure of 3 bar, or 36 lbs/hr at 43.5 psi. is there a pin on the DME connector that goes to it I found the male half of the DME online so I am using it as my interface so I don't have to cut into the stock wiring. I though that since I'm using larger inj it would have a shorter pulse width? but main reason is just for functionality of gauge seems to just bounce all over the place now...
Correct, which is the same reason why I stated mine would never be accurate.
Originally Posted by Dwizle
Another question i have after reading another one of your post you say the stock inj actually flow is 22 lbs because the stock FPR is not set to 3 bar so how would i cal what these inj are actually flowing right now also inj dead time I have the value for Latency (dead time)@ 12volts=0.621 ms@ 14volts=0.391 ms. MS II asks for V at 13v?? right I have it set around 510 ms.
Trying to tune for cold weather 30 deg n below...
For dead time, it's important that you find a figure either from the manufacturer, or from someone else who has already figured out what it is. Many injectors come with a data sheet with this voltage/dead time curve. This is what MS is expecting as that input.
Originally Posted by 924srr27l
Surely a Dyno Session would greatly assist the tune? or does the MS software allow you to record and change parameters in real time road driving ?
Why RPM did the 951 come on boost? I'm keen to try a stock 951 or 3.0 S2 as a comparison, I did try a friend's 3.8 Gen 2 997 at the weekend and he drove the 924S that was an interesting comparison for both of us!
R
A dyno tune would help but after 1.5 years, the tune is rock solid. I have the AFRs I want everywhere, so my fuel map requires no tweaking. My spark map is the only thing I'd have dyno tuned, but I've gotten enough info from other tunes that I know my map is pretty spot on for an 8v NA. It's very drivable and there are no dead spots or detonation areas.
Dougs951s or Micheal have either of you guys tried using the base maps out of a stock DME to use as a base tune came across the Bin and XDF files for a 944 trying figure out if I can convert them to a format MS can use?
It's been about 2 years more or less since installing the MS into my '83. I'm still driving this car daily (unless the weather is crappy) so I made a video about where the car is today. It's come a long way... I've graduated college, started a full time job, and slowly made this NA into a car that I'm truly proud of. When I first started this project in 2015, I was working out of my mom's driveway and had less than $1000 in my checking account. The '83 was solid but still had a lot of rough edges, and was my only car. Now I have a few others but it's still my favorite, even over my 951 (which is getting a MS a well, big shock).
I also went over a few technical areas which I can't remember if I ever hashed out in my original posts. The only issues with the car have been a leaking hose, a seized up cooling fan, and a cracked pressure plate. The engine starts every time and still runs amazingly.
10-09-2015, 08:09 PM
