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Frank S
Hi there,
I found so much usefull information about Megasquirt/Microsquirt here, so first I would like to take the opportinity to say thanks to everybody who posted informtion about MS here before as it all provided good guidance to me when I was planning my own project.

My motivation:
I'm running a 9590 camed 2056, which pulls strong but not as good as expected. Problem is, that cruise speeds here could be much higher as the once you are used to in the US and if I eliminate the lean spot above 4000 RPM cruising, I'm running too rich in cold start conditions and also overrun conditions are too rich.
I still wanted to keep the stock look of the engine bay, so I will keep the distributor and integrate the MS2V3 board into the original D-Jet housing and use the original relayboard to power the MS and the Fuel Pump.

MS set-up:
Batch Semi Sequential Injection
Speed density %Baro fueling
TPS based accelaration enrichment
ATM correction (second MAP Sensor on PCB)
EGO Sensor: Spartan II
Ignition: Single coil with fixed distributor and BIP373
Idle Valve: Curently none, using only original CSV, will add stepper type idle valve later (my own design, also stealth type)
Oil temp sensor
Bluetooth communication

Sensors (modified original MAT Sensor, TPS Sensor, BMW CHT Sensor):
Click to view attachment

Oil Temp Sensor with adapter:
Click to view attachment

Oil Temp Sensor mounted:
Click to view attachment

High-Z Injectors:
Click to view attachment

ECU and cable set original version:
Click to view attachmentClick to view attachment


ECU and cable set after modification (adapter for original D-Jet connector, including Oil Temp Sensor and 2nd EGO Sensor option, better strain relief as first version):
Click to view attachmentClick to view attachment


Relayboard original version:
Click to view attachment Click to view attachment

Relayboard modified (removed relay just added fuses) only mounted picture available, still in fold out design:
Click to view attachment

Engine Bay with MS installed:
Click to view attachment Click to view attachment

Engine is running, idle is perfect, cold start behaviour is good, just need to get out to drive and tune the fuel tables before I go to a dyno shop for adjusting the ignition table.

I'm very happy with the installation and as you learn while you work on the project, everything went really well.
There is also perfect support on the Megasquirt forums.

The only thing I really struggled with was EMI problems caused by the ignition system, after upgrading to Magnecor spark wires that problem was solved.

Cheers and stay safe,
Frank
Montreal914
Frank thank you for sharing you nice installation. smilie_pokal.gif

I like the hinge concept under the relay board. The integration in the original ECU box is also very clean.

Are you using the oil temperature as an input in the MS, or simply for readout?

Cheers! beerchug.gif
Frank S
Are you using the oil temperature as an input in the MS, or simply for readout?

Cheers! beerchug.gif
[/quote]

I'm using the oil temperature as an input in the MS (one of the two extra ADC's), can display it with ShadowDash while driving and could also use it with MegaLogviewer when I play around with ignition timing.
Frank S
Testing if the Steper Idle Valve fits to the plenum...
Fits perfect and is working flawless.

After quarantaine it will go into the car.
Click to view attachment

Click to view attachment
rudedude
What idle stepper valve is that? I have never been happy with the one I am using.
peteyd
Frank,

Very clean install, looks great. I like your Oil Temp Sensor with adapter. Is that some you machined up yourself or did you purchase that unit?

I also like your printed idle stepper valve mount. Nice work

Pete
GregAmy
QUOTE(rudedude @ Apr 20 2020, 09:28 AM) *

What idle stepper valve is that? I have never been happy with the one I am using.

I'm running w/o idle control at all in my 2L D-Jet Microsquirt install. I'm bracketing my desired idle RPM with ignition and fuel and it's working well. Tickle the throttle pedal for 30 seconds or so after startup (I'd do that anyway to let the oil ciruclate) and off I go.
Frank S
QUOTE(rudedude @ Apr 20 2020, 04:28 PM) *

What idle stepper valve is that? I have never been happy with the one I am using.


I'm using this one:
https://www.autoteiledirekt.de/ridex-8149366.html

What is the problem with the one you are using?
I'm not planning to run this closed loop. It should just replace the AAR.
Engine is idling very smooth when fully warmed up, but original AAR is providing not enough air when cold.
Mueller
Very clean and organized, I like.
Frank S
QUOTE(peteyd @ Apr 20 2020, 04:40 PM) *

Frank,

Very clean install, looks great. I like your Oil Temp Sensor with adapter. Is that some you machined up yourself or did you purchase that unit?

I also like your printed idle stepper valve mount. Nice work

Pete


Hi Pete,
thanks :-)

I'm using this one:
https://www.amazon.de/streetandtrack-%C3%96...r/dp/B01MR92EJ9
Frank S
QUOTE(GregAmy @ Apr 20 2020, 05:18 PM) *

QUOTE(rudedude @ Apr 20 2020, 09:28 AM) *

What idle stepper valve is that? I have never been happy with the one I am using.

I'm running w/o idle control at all in my 2L D-Jet Microsquirt install. I'm bracketing my desired idle RPM with ignition and fuel and it's working well. Tickle the throttle pedal for 30 seconds or so after startup (I'd do that anyway to let the oil ciruclate) and off I go.


I added this because the original AAR (w/o changing the calibration) does not provide enough air to run the engine at slightly elavated RPM during warm up. My target was perfect warm up behaviour.
56kabrio
QUOTE(Mueller @ Apr 20 2020, 07:41 AM) *

Very clean and organized, I like.



Typisch Deutsch, nein? Sehr schoene Montage!

Ciao

Mack
Frank S
QUOTE(Mueller @ Apr 20 2020, 05:41 PM) *

Very clean and organized, I like.

piratenanner.gif cheer.gif
Thanks!
Frank S
QUOTE(56kabrio @ Apr 20 2020, 06:41 PM) *

QUOTE(Mueller @ Apr 20 2020, 07:41 AM) *

Very clean and organized, I like.



Typisch Deutsch, nein? Sehr schoene Montage!

Ciao

Mack

piratenanner.gif cheer.gif
Danke, ich gebe mir mühe...
56kabrio
QUOTE(Frank S @ Apr 20 2020, 08:48 AM) *

QUOTE(56kabrio @ Apr 20 2020, 06:41 PM) *

QUOTE(Mueller @ Apr 20 2020, 07:41 AM) *

Very clean and organized, I like.



Typisch Deutsch, nein? Sehr schoene Montage!

Ciao

Mack

piratenanner.gif cheer.gif
Danke, ich gebe mir mühe...



Es zeigt. Sehr gut gemacht. aktion035.gif

Mack

GregAmy
QUOTE(Frank S @ Apr 20 2020, 10:50 AM) *

QUOTE(GregAmy @ Apr 20 2020, 05:18 PM) *

QUOTE(rudedude @ Apr 20 2020, 09:28 AM) *

What idle stepper valve is that? I have never been happy with the one I am using.

I'm running w/o idle control at all in my 2L D-Jet Microsquirt install. I'm bracketing my desired idle RPM with ignition and fuel and it's working well. Tickle the throttle pedal for 30 seconds or so after startup (I'd do that anyway to let the oil ciruclate) and off I go.


I added this because the original AAR (w/o changing the calibration) does not provide enough air to run the engine at slightly elavated RPM during warm up. My target was perfect warm up behaviour.

I'm running without an AAR, too.
saigon71
Beautiful work Frank! beerchug.gif
JamesM
Looking good! Did you make that adapter board or is someone producing those now? What are you using for your ignition signal?
913B
beerchug.gif popcorn[1].gif

Keep up the great work, subscribed smile.gif
Frank S
QUOTE(saigon71 @ Apr 21 2020, 12:25 AM) *

Beautiful work Frank! beerchug.gif


Thanks Bob beerchug.gif
Frank S
QUOTE(JamesM @ Apr 21 2020, 07:06 AM) *

Looking good! Did you make that adapter board or is someone producing those now? What are you using for your ignition signal?


Hi James,
I made the adapterboard myself, as I couldn't find one.

Click to view attachment

For the ignition signal I'm using a modified distributor with fixed shaft and optical pic up.
Running the MS with the BIP373 and single coil.
This is because I want to keep the original look and it provides reasonable ignition timing controll.
Don't have a pic, will post one later, do not have access to the car right now as I'm under quarantaine...
JamesM
QUOTE(Frank S @ Apr 21 2020, 02:21 AM) *

QUOTE(JamesM @ Apr 21 2020, 07:06 AM) *

Looking good! Did you make that adapter board or is someone producing those now? What are you using for your ignition signal?


Hi James,
I made the adapterboard myself, as I couldn't find one.

Click to view attachment

For the ignition signal I'm using a modified distributor with fixed shaft and optical pic up.
Running the MS with the BIP373 and single coil.
This is because I want to keep the original look and it provides reasonable ignition timing controll.
Don't have a pic, will post one later, do not have access to the car right now as I'm under quarantaine...


I did something similar with one of my earlier MS builds (having the same goals in mind) only I just use jumper wires to the connector rather than a printed PCB. that is very clean, I love it!

Are you having any issues with cold starts when using the 4 point pickup? I would have issues whenever it got cold enough (or my battery was low enough) to slow my cranking where the timing would become inaccurate enough to have trouble starting. I highly recommend the 36 tooth wheel and sensor from thedubshop.com. It produces a ridiculously clean signal and it well hidden when installed.

for a while i toyed with the idea of a custom PCB to adapt the microsquirt module https://www.diyautotune.com/product/microsquirt-module-v2-2/ to run on a stock d-jet harness but years of running MS on a stock d-jet harness really highlighted its shortcommings, at least as far as modernizing the whole system, way to much signal noise due to the grounding arrangement.
Frank S
Hi James,
see below:


I did something similar with one of my earlier MS builds (having the same goals in mind) only I just use jumper wires to the connector rather than a printed PCB. that is very clean, I love it!

Thanks!

Are you having any issues with cold starts when using the 4 point pickup? I would have issues whenever it got cold enough (or my battery was low enough) to slow my cranking where the timing would become inaccurate enough to have trouble starting. I highly recommend the 36 tooth wheel and sensor from thedubshop.com. It produces a ridiculously clean signal and it well hidden when installed.

I have the 36-1 tooth wheel from Mario mounted, but had allways issues with sync. loss at plus 4000 RPM and above. After I had that fixed, I had heat soak problems and had sync loss again with fully hot engine (might be some problem with the sensor).
As I didn't want to drop the engine again, I came up with the other solution and it is working flawless, but didn't try to start below -6°C as it wasn't any colder this winter...
I agree, there are advantages using the 32-1 tooth wheel as Ignition timing is more acurate, but I had the distributer refurbished/rebushed before installing the optical pic up. So it is at least like +-1° acurate for ignition timing and I think i can life with that for now.


for a while i toyed with the idea of a custom PCB to adapt the microsquirt module https://www.diyautotune.com/product/microsquirt-module-v2-2/ to run on a stock d-jet harness but years of running MS on a stock d-jet harness really highlighted its shortcommings, at least as far as modernizing the whole system, way to much signal noise due to the grounding arrangement.
[/quote]

I was looking into this as well, but since I don't have electronics background I didn't want to make life more complicatad by using the module, as I could not find much information about it. But would love to integrate it...

I've also choosen the High-Z Injectors for avoiding EMI Problems within the injection harness. Just trying to avoid what I potentialy could struggle with...

VaccaRabite
When I did my MS2 setup, we had to use a shielded wire for the hall sensor that picked up the trigger wheel on the crank. Otherwise there were noise issues that you noted. I would imagine that since you are using long plug wires instead of COP or CNP the noise issue is even more of an issue.

But I'd still try using the grounded and shielded wire from the pickup to the MS2. Did me a world of good.

Zach
JamesM
QUOTE(Frank S @ Apr 22 2020, 07:20 AM) *


I have the 36-1 tooth wheel from Mario mounted, but had allways issues with sync. loss at plus 4000 RPM and above. After I had that fixed, I had heat soak problems and had sync loss again with fully hot engine (might be some problem with the sensor).
As I didn't want to drop the engine again, I came up with the other solution and it is working flawless, but didn't try to start below -6°C as it wasn't any colder this winter...
I agree, there are advantages using the 32-1 tooth wheel as Ignition timing is more acurate, but I had the distributer refurbished/rebushed before installing the optical pic up. So it is at least like +-1° acurate for ignition timing and I think i can life with that for now.




That is interesting. Out of curiosity are you running 5v or 12v to the sensor? Supposedly it will run on either but i have had much better luck running 12v to it. Loss over 4k rpm could be a depth/alignment issue as well. I have seen that sensor bench tested to over 17k RPM its normally a pretty robust unit. Triggering from the distributor is a workable solution but i was blown away at the difference that can been seen between the two with a timing light.
Frank S
QUOTE(VaccaRabite @ Apr 22 2020, 10:05 PM) *

When I did my MS2 setup, we had to use a shielded wire for the hall sensor that picked up the trigger wheel on the crank. Otherwise there were noise issues that you noted. I would imagine that since you are using long plug wires instead of COP or CNP the noise issue is even more of an issue.

But I'd still try using the grounded and shielded wire from the pickup to the MS2. Did me a world of good.

Zach


Hi Zach,
agreed. I had to replace Spark Plug Wires also to overcome that problem, using Magnecore now.
I used the shielded wire from the original Megasquirt Harness so far and as it is not the best one, here what I use for the next build:

Click to view attachment

Frank S
That is interesting. Out of curiosity are you running 5v or 12v to the sensor? Supposedly it will run on either but i have had much better luck running 12v to it. Loss over 4k rpm could be a depth/alignment issue as well. I have seen that sensor bench tested to over 17k RPM its normally a pretty robust unit. Triggering from the distributor is a workable solution but i was blown away at the difference that can been seen between the two with a timing light.
[/quote]

I'm running the sensor with 12V.
Distance beween Sensor and Triggerwheel is set to 2mm gap.
And yes, you are right, the timing is rock solid with the trigger wheel set-up.
But the season is on already and I want to drive NOW and not drop the engine again...
For the next build I'll probably use a VR Sensor with proper shielded cable. Cable routed seperated from other cables and using a additional VR Signal Conditioner as I don't wnt to deal with the pots of the MS...
Frank S
Was out driving to dial in the VE Table last weekend and after 6 hours in total, I'm almost there!

Today I had a chance today to mount the Stepper AAR valve.
AAR body mounted to plenum:

Click to view attachment

Complete unit mounted:

Click to view attachment

Fits perfect and is working well too piratenanner.gif
Frank S
Had also a chance today to take a pic of the modified distributor as promised some time ago:

Click to view attachment

Within 6 hours of hard driving and reving the engine up high, I did not experience a single sync. loss...
Frank S
Was driving and tuning alot and learned so much withing the last few weeks.

1. The engine does not like random injection timing that much. AFR tuning is different inbetween engine starts which makes perfect tuning impossible.
Fixed that with a 60-2 Trigger Wheel inside the dizzy and running semi sequential now. Like this I have much better idle stability and repetable AFR's.
Click to view attachment

2. With the MAT Sensor in the original position inside the manifold I'm experiencing heat soak problems. This caused the engine running lean after hotstart and also while running when fully warm.
Fixed that by using a open sensor element, positioned inside the snorkel of the airfilterbox.
Click to view attachment

3. During full load pulls I realized that the Manifoldpressure is decreasing above 4800 RPM. This is not jet fixed, but I'm waiting for a new throttle body which will have a 2mm larger bore diameter to adress this.

All in all im very happy with the setup now, still working on it and hope I can take it to a dyno this season...
VaccaRabite
Dyno is the way to go for tuning.
I'd love yo see your numbers when you get off the dyno.

I'm planning to put my car back on a dyno this summer too after I get the new exhaust from Ben.

Zach
Frank S
QUOTE(VaccaRabite @ Jul 6 2020, 05:30 PM) *

Dyno is the way to go for tuning.
I'd love yo see your numbers when you get off the dyno.

I'm planning to put my car back on a dyno this summer too after I get the new exhaust from Ben.

Zach


Hi Zach,

I had planned to put the car on a dyno for some time already, but on the other hand, putting it on the dyno to early would be a waste of money (if there are still other issues, like mine with the MAT influencing results or going with a not optimised engine like to small TB).
Will also try two different exhaust set-ups and take the more promissing one to the dyno. This stupid virus delayed so much...

Will defanetely share date, as soon they are available.

Kind regards,
Frank
Frank S
Installed the lager TB last weekend and drove it many hours.

Click to view attachment

Results look good, intake restriction has gone.

Comparing data, I found that I have repeatable engine operation now. Installing the MAT Sensor in a different place is the main contributor I think.
Here I figured that the delta in is almost 20°C from the previous mounting position to the new one and on top of this in the old position it just stayed hot while driving after a hot start of the engine. In the new position it adapts the temp. within very short amount of time.

Continuing street tuning...

Just need to tidy up all the vac.- and ventlines...
JeffBowlsby
Whats in the MPS case?
Frank S
QUOTE(JeffBowlsby @ Jul 14 2020, 06:34 PM) *

Whats in the MPS case?


Hi Jeff,
I want to keep the look original therefore the MPS is still mounted, but the vacuum line is pluged at the manifold side.
So the MPS is still original but without any specific function.
ClayPerrine
QUOTE(Frank S @ Jul 14 2020, 01:16 PM) *

QUOTE(JeffBowlsby @ Jul 14 2020, 06:34 PM) *

Whats in the MPS case?


Hi Jeff,
I want to keep the look original therefore the MPS is still mounted, but the vacuum line is pluged at the manifold side.
So the MPS is still original but without any specific function.



I would have put the MAP sensor in there.

Frank S
I would have put the MAP sensor in there.
[/quote]

Hi Clay,

that would be true for Microsqurt. The MS2V3 board has a onboard MAP Sensor and I'm using that one.
Frank S
Hi all,

is there anybody else running a %baro set-up?
If so, how does your baro correction table look like?

This would be the next point I need to address and I would appreciate any input...

Best Regards,
Frank
JamesM
QUOTE(Frank S @ Jul 14 2020, 12:46 PM) *

Hi all,

is there anybody else running a %baro set-up?
If so, how does your baro correction table look like?

This would be the next point I need to address and I would appreciate any input...

Best Regards,
Frank



I recently switched from running speed density to %baro, I haven't done any extensive tuning though as i have some other changes in the works. One thing to point out though is that the barometric correction is not specific to running %baro, it gets applied to all the fueling algorithms in the same way. That being said, I did some pretty extensive tuning (including high altitude runs) on a 914 running ITBs in hybrid Alpha-N and dual MAP sensors and found the stock baro correction table was pretty good. Unless you plan on doing a lot extreme altitude changes I wouldn't to much about it, at least i wouldn't make it a tuning priority.

My reason for switching to %baro was solely to get more usable area in the fuel map. Where I live I only see about ~83-85kpa atmospheric pressure and the passes at the top of the mountains around here im only seeing ~70kpa. this becomes problematic 1. in that the usable tuning bins is reduced using speed density and 2. Living at altitude I am unable to tune speed density bins in the 85+ kpa range that i would need for driving at lower altitude. %baro takes care of both those issues in that bins represent calculated load rather than absolute pressure, allowing you to hit all load%s at any altitude. Only reason i was running speed density in the first place was because %baro didnt exist in the code when i started this 15+ years ago biggrin.gif
JamesM
QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

Was driving and tuning alot and learned so much withing the last few weeks.

1. The engine does not like random injection timing that much. AFR tuning is different inbetween engine starts which makes perfect tuning impossible.
Fixed that with a 60-2 Trigger Wheel inside the dizzy and running semi sequential now. Like this I have much better idle stability and repetable AFR's.
Click to view attachment


I am REALLY curious about that distributor wheel setup. I know a couple people who are looking for something pretty much exactly like that. Are those available parts or did you custom make that? In my experience having a high tooth count wheel makes all the difference but installing a crank trigger requires dropping the motor. Having a part like this available would make life easier for a lot of people.


QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

2. With the MAT Sensor in the original position inside the manifold I'm experiencing heat soak problems. This caused the engine running lean after hotstart and also while running when fully warm.
Fixed that by using a open sensor element, positioned inside the snorkel of the airfilterbox.


^everyone should be aware this is an issue when doing an MS conversion on a 914. Pretty sure this sensor placement issue is responsible for some of the hot mixture issues on d-jet cars as well. The 1.7 sensor location is slightly better as its directly in the air flow behind the TB, but its still a closed element sensor encased in a metal plenum, so not good.



QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

3. During full load pulls I realized that the Manifoldpressure is decreasing above 4800 RPM. This is not jet fixed, but I'm waiting for a new throttle body which will have a 2mm larger bore diameter to adress this.



I am running a 2056 on a modified 1.8 plenum with a 50mm vanagon TB and a fully open cone filter and I am getting high RPM manifold pressure drop as well. Granted i have a pretty hot cam in my motor, i am not sure if you will be able to go large enough on a stock TB casting to completely remove all restrictions. I suspect the 2L air box may also prove to be a restriction as the snorkel chokes down pretty small.
ClayPerrine
QUOTE(Frank S @ Jul 14 2020, 03:39 PM) *

I would have put the MAP sensor in there.

Hi Clay,

that would be true for Microsqurt. The MS2V3 board has a onboard MAP Sensor and I'm using that one.



Reprogram the megasquirt to use the one on the board for baro and use an external in the old MPS housing as MAP.


biggrin.gif
Frank S
QUOTE(JamesM @ Jul 15 2020, 01:00 AM) *

QUOTE(Frank S @ Jul 14 2020, 12:46 PM) *

Hi all,

is there anybody else running a %baro set-up?
If so, how does your baro correction table look like?

This would be the next point I need to address and I would appreciate any input...

Best Regards,
Frank



I recently switched from running speed density to %baro, I haven't done any extensive tuning though as i have some other changes in the works. One thing to point out though is that the barometric correction is not specific to running %baro, it gets applied to all the fueling algorithms in the same way. That being said, I did some pretty extensive tuning (including high altitude runs) on a 914 running ITBs in hybrid Alpha-N and dual MAP sensors and found the stock baro correction table was pretty good. Unless you plan on doing a lot extreme altitude changes I wouldn't to much about it, at least i wouldn't make it a tuning priority.

My reason for switching to %baro was solely to get more usable area in the fuel map. Where I live I only see about ~83-85kpa atmospheric pressure and the passes at the top of the mountains around here im only seeing ~70kpa. this becomes problematic 1. in that the usable tuning bins is reduced using speed density and 2. Living at altitude I am unable to tune speed density bins in the 85+ kpa range that i would need for driving at lower altitude. %baro takes care of both those issues in that bins represent calculated load rather than absolute pressure, allowing you to hit all load%s at any altitude. Only reason i was running speed density in the first place was because %baro didnt exist in the code when i started this 15+ years ago biggrin.gif


Hi James, thanks thats good information. I was reading alot about the barometric correction and there is alot of conflicting informantion around.
I thought the correction was just a table look up from the baro correction table...

If the fuel map is better dialed in I'll just try to go to higher altitudes and try out what it does, without spending to much attention to it.

Are you runnig your Ignition timing also %Baro based or still on Speed Density?
Frank S
QUOTE(JamesM @ Jul 15 2020, 01:17 AM) *

QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

Was driving and tuning alot and learned so much withing the last few weeks.

1. The engine does not like random injection timing that much. AFR tuning is different inbetween engine starts which makes perfect tuning impossible.
Fixed that with a 60-2 Trigger Wheel inside the dizzy and running semi sequential now. Like this I have much better idle stability and repetable AFR's.
Click to view attachment


I am REALLY curious about that distributor wheel setup. I know a couple people who are looking for something pretty much exactly like that. Are those available parts or did you custom make that? In my experience having a high tooth count wheel makes all the difference but installing a crank trigger requires dropping the motor. Having a part like this available would make life easier for a lot of people.

This is regular available from a small company in Germany. They could modify the dizzy or also supply the parts for the modification as far as I know.
The beauty of the 60-2 wheel at Cam speed is that you can run semi sequential without any other sensor required and in spar timing accuracy you just give up like +/- 1° it's not as good as a crank trigger but much much better then the original dizzy.
And yes, the huge advantage is that you don't need to drop the engine to install it and also not if you have a failed sensor.
It's producing a clean squarewave signal and I haven't experienced any EMV/Noise problems asosiated with it.



QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

2. With the MAT Sensor in the original position inside the manifold I'm experiencing heat soak problems. This caused the engine running lean after hotstart and also while running when fully warm.
Fixed that by using a open sensor element, positioned inside the snorkel of the airfilterbox.


^everyone should be aware this is an issue when doing an MS conversion on a 914. Pretty sure this sensor placement issue is responsible for some of the hot mixture issues on d-jet cars as well. The 1.7 sensor location is slightly better as its directly in the air flow behind the TB, but its still a closed element sensor encased in a metal plenum, so not good.



QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

3. During full load pulls I realized that the Manifoldpressure is decreasing above 4800 RPM. This is not jet fixed, but I'm waiting for a new throttle body which will have a 2mm larger bore diameter to adress this.



I am running a 2056 on a modified 1.8 plenum with a 50mm vanagon TB and a fully open cone filter and I am getting high RPM manifold pressure drop as well. Granted i have a pretty hot cam in my motor, i am not sure if you will be able to go large enough on a stock TB casting to completely remove all restrictions. I suspect the 2L air box may also prove to be a restriction as the snorkel chokes down pretty small.


I thought the 2.0 plenum is so bad, that the original TB is not the restriction, but data has proven it was a restriction.
I've just checked again, the new TB diameter is 48mm and with that mod the restriction has gone (probably a combination of the mild cam in combination with the poor 2.0 plenum...
Drivability is still phantastic with 48mm as well.
Frank S
QUOTE
Reprogram the megasquirt to use the one on the board for baro and use an external in the old MPS housing as MAP.


biggrin.gif


Hi Clay, I don't see the advantage of the sugested mod.
Both Sensors are mounted on board inside the ECU case. Like that everything is shielded well and close to the signal processor. I also do not habe pins left at the D-Jet connector...
And whay destroying a perfect working MPS?
ClayPerrine
QUOTE(Frank S @ Jul 15 2020, 12:41 PM) *

QUOTE
Reprogram the megasquirt to use the one on the board for baro and use an external in the old MPS housing as MAP.


biggrin.gif


Hi Clay, I don't see the advantage of the sugested mod.
Both Sensors are mounted on board inside the ECU case. Like that everything is shielded well and close to the signal processor. I also do not habe pins left at the D-Jet connector...
And whay destroying a perfect working MPS?



I am just thinking of how to make it a stealth install. By using the MPS as the mount for the MAP, you don't have to run a vacuum line to the megasquirt, and the wiring is already there on the D-Jet harness and connector. And nobody can see the changes.

Also, I would only do this on a dead MPS, not a good working one.



Frank S
QUOTE(ClayPerrine @ Jul 16 2020, 03:21 PM) *

QUOTE(Frank S @ Jul 15 2020, 12:41 PM) *

QUOTE
Reprogram the megasquirt to use the one on the board for baro and use an external in the old MPS housing as MAP.


biggrin.gif


Hi Clay, I don't see the advantage of the sugested mod.
Both Sensors are mounted on board inside the ECU case. Like that everything is shielded well and close to the signal processor. I also do not habe pins left at the D-Jet connector...
And whay destroying a perfect working MPS?



I am just thinking of how to make it a stealth install. By using the MPS as the mount for the MAP, you don't have to run a vacuum line to the megasquirt, and the wiring is already there on the D-Jet harness and connector. And nobody can see the changes.

Also, I would only do this on a dead MPS, not a good working one.


Ahhh now I get your point. Yes under the Stealth point of view I totally agree. But some minimal compromises I needed to accept.
I would under no circumstances run without the Stepper Valve which is substituting the AAR as it gives engine start up apperarance like stock or better with a none stock engine. But the Stepper Valve requires 4 cables to operate it and I wanted to implement a oil temp sender too, so I'm simply running out of pins on the 25 pin D-Jet connector.
VaccaRabite
QUOTE(Frank S @ Jul 17 2020, 03:09 AM) *


Ahhh now I get your point. Yes under the Stealth point of view I totally agree. But some minimal compromises I needed to accept.
I would under no circumstances run without the Stepper Valve which is substituting the AAR as it gives engine start up apperarance like stock or better with a none stock engine. But the Stepper Valve requires 4 cables to operate it and I wanted to implement a oil temp sender too, so I'm simply running out of pins on the 25 pin D-Jet connector.


Oh, simple fix there.
Use a 2 or 3 wire IAC instead of a 4 wire stepper motor valve.
I'm using a 3 wire. It was dead easy to wire in, and it only fills one pin on the Microsquirt.

For a 3 wire setup, 2 wires go to ground. One of them goes through a resistor (i'm using 40ohm), and remaining wire goes to the ecu. It does not matter which ground gets the resistor, though it may change the curve in TunerStudio for controlling the valve.

Zach
jd74914
QUOTE(Frank S @ Jul 15 2020, 12:34 PM) *

QUOTE(JamesM @ Jul 15 2020, 01:17 AM) *

QUOTE(Frank S @ Jul 6 2020, 05:28 AM) *

Was driving and tuning alot and learned so much withing the last few weeks.

1. The engine does not like random injection timing that much. AFR tuning is different inbetween engine starts which makes perfect tuning impossible.
Fixed that with a 60-2 Trigger Wheel inside the dizzy and running semi sequential now. Like this I have much better idle stability and repetable AFR's.


I am REALLY curious about that distributor wheel setup. I know a couple people who are looking for something pretty much exactly like that. Are those available parts or did you custom make that? In my experience having a high tooth count wheel makes all the difference but installing a crank trigger requires dropping the motor. Having a part like this available would make life easier for a lot of people.


This is regular available from a small company in Germany. They could modify the dizzy or also supply the parts for the modification as far as I know.
The beauty of the 60-2 wheel at Cam speed is that you can run semi sequential without any other sensor required and in spar timing accuracy you just give up like +/- 1° it's not as good as a crank trigger but much much better then the original dizzy.
And yes, the huge advantage is that you don't need to drop the engine to install it and also not if you have a failed sensor.
It's producing a clean squarewave signal and I haven't experienced any EMV/Noise problems asosiated with it.


Would you mind sharing the company name Frank? smile.gif I have a 16 toothed wheel that fits in the distributor in place of the rotor, but I like this optical solution much better.
Frank S
QUOTE(VaccaRabite @ Jul 17 2020, 05:16 PM) *

QUOTE(Frank S @ Jul 17 2020, 03:09 AM) *


Ahhh now I get your point. Yes under the Stealth point of view I totally agree. But some minimal compromises I needed to accept.
I would under no circumstances run without the Stepper Valve which is substituting the AAR as it gives engine start up apperarance like stock or better with a none stock engine. But the Stepper Valve requires 4 cables to operate it and I wanted to implement a oil temp sender too, so I'm simply running out of pins on the 25 pin D-Jet connector.


Oh, simple fix there.
Use a 2 or 3 wire IAC instead of a 4 wire stepper motor valve.
I'm using a 3 wire. It was dead easy to wire in, and it only fills one pin on the Microsquirt.

For a 3 wire setup, 2 wires go to ground. One of them goes through a resistor (i'm using 40ohm), and remaining wire goes to the ecu. It does not matter which ground gets the resistor, though it may change the curve in TunerStudio for controlling the valve.

Zach


Hi Zach,

wanted to stay with Stepper Valve as I want to keep original look and Stepper IAC is more suitable for that, I had sticked with this and my own design...

B.R.
Frank
Frank S

Would you mind sharing the company name Frank? smile.gif I have a 16 toothed wheel that fits in the distributor in place of the rotor, but I like this optical solution much better.
[/quote]

Hi Jim,

sorry for my late reply, I was very busy with tuning as I was finally able to get an appointment with a dyno shop...

However, inbetween I was in contact with my supplier. Unfortunately they do not want to sell to the US, as there are to many hurdles in place.

But, if you need something, just PM me and I'll try to find a solution for you.

Take care,
Frank
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