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Summer build thread: Megasquirt and more...

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Old 05-14-2015, 10:20 PM
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V2Rocket
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I know you had asked about this the other day on FB...
I can confirm the 951 TB and 944 TPS / 944TB/951TPS are mechanically interchangeable, as far as fitting shaft/bolting up/activating idle contact switch.
Old 05-15-2015, 08:05 AM
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Great to read about your plans

Its a great way forward to modernize the technology on the car and hopefully get better performance, economy and hopefully if well installed, reliability.

I have been researching similar options, I am really keen for this project because of how much im hoping I will learn

I have also got a new set of LS coils that willl be going towards the project. I have done some online reading but have yet to settle on how best to do the crank sens set up. I will try and read more to see what are proven sensor combos with the Microsquirt if you have any wisdom there?

I was also looking at the different set ups, whether just to use the Microsquirt in its standard casing, or order a board and a larger casing and putting in SD card slot for datalog USB sockert etc and to have the option of further upgrades.

Do you plan to go AFM or MAP?
Old 05-15-2015, 01:14 PM
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odonnell
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Originally Posted by V2Rocket_aka944
I know you had asked about this the other day on FB...
I can confirm the 951 TB and 944 TPS / 944TB/951TPS are mechanically interchangeable, as far as fitting shaft/bolting up/activating idle contact switch.
Perfects, thanks again for looking into that.

Originally Posted by willrobinson
Great to read about your plans

Its a great way forward to modernize the technology on the car and hopefully get better performance, economy and hopefully if well installed, reliability.

I have been researching similar options, I am really keen for this project because of how much im hoping I will learn

I have also got a new set of LS coils that willl be going towards the project. I have done some online reading but have yet to settle on how best to do the crank sens set up. I will try and read more to see what are proven sensor combos with the Microsquirt if you have any wisdom there?

I was also looking at the different set ups, whether just to use the Microsquirt in its standard casing, or order a board and a larger casing and putting in SD card slot for datalog USB sockert etc and to have the option of further upgrades.

Do you plan to go AFM or MAP?
For a crank signal, the flywheel has 130 teeth, so 2.77 degrees per tooth (not an integer). That's fine for the DME because it processes the signal in a special way. I suggest reading this: http://the944.com/math.htm
So you can use the stock sensors with MS but it won't be plug and play, you'll have to do some footwork.

IMO the logical thing to do is get a trigger wheel which mounts behind the crank pulley. Easy access, and you have a lot of options for sensors (no more paying the man $60 per sensor or dealing with degrading connectors).
http://www.goingsuperfast.com/Trigger-wheels.html

For intake measurements I'm using a MAP because it's just hooking up a vacuum line and will make tuning easier. I looked at MAFs but couldn't find a reason when GM 1 bar MAPs are so plentiful and MS already has the transfer function. Bottom line, the AFM is the last thing I would put in the setup. Garbage!

Keep us updated on your project!
Old 05-17-2015, 05:51 PM
  #19  
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Weekend update: ordered the POR15 super starter kit to treat the rust, as recommend by those who have done it before. Have made an Excel sheet with all MicroSquirt parts, sensors, and the like. Item, price, and URL. Once it's relatively finalized I'll post it for those interested in converting a NA 944 to standalone.

EDIT: MicroSquirt ordered! Along with GM IAT and a DIYAutoTune hall effect sensor.

I made the decision to maintain the factory idle valve ("auxiliary air valve"). I have a couple that work well, and it's open loop, so one less thing to set up. I know it will work well with this engine.

The other reason is that I want to use the FIDLE pin (which normally drives an idle valve) on the MS controller to trigger a fan relay. This relay will replace the fan switch in the radiator. My reason is this: I have had to replace it twice in two years, and the 3rd one just crapped out last night after a long drive. I'm tired of dicking around with the part and want to hand it off to a dedicated relay. The FIDLE function in MS is triggered by coolant temp as a variable, so it will work exactly as before, but using the coolant temp sensor instead of a dedicated thermoswitch in the radiator.

Current vision: Have a universal relay panel and 8-gang fuse block in a waterproof box, located in the area where it would be on a late 944. There are 3 new relays (DME relay in garbage can): the main relay for powering MS and the injectors, the fuel pump relay, and the new fan control relay. The fuse block is there to hold the fuses that will need to be added (heated o2 sensor, other stuff related to MS).

Last edited by odonnell; 05-17-2015 at 08:12 PM.
Old 05-20-2015, 11:23 PM
  #20  
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Received the first round of MS parts today: the actual controller, 8 foot harness, hall effect crank sensor, and GM IAT. Also have been tackling my interior - it was a fungal warzone on the passenger side and the sound deadening disintegrated when I pulled it up. Replaced it all with fat mat (equivalent) stuff and treated the carpet with Odo-Ban and pressure washed outside the car. Also resealed a leaking tail light. Expecting more MS parts soon...trigger wheel and 951 TPS are in the mail.

















Old 05-22-2015, 12:11 AM
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I subscribed to this as I will be back on my megasquirt project next week if I pick up this NA beater this weekend.
I plan doing fuel only at first then adding spark later, I will be using a flywheel from an 87 S which is 62-2.
Old 05-23-2015, 12:50 AM
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Default Summer build thread: Megasquirt and more...

Originally Posted by jeffro951
I subscribed to this as I will be back on my megasquirt project next week if I pick up this NA beater this weekend.
I plan doing fuel only at first then adding spark later, I will be using a flywheel from an 87 S which is 62-2.
What injectors are you looking at running?
Old 05-23-2015, 01:38 AM
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Well I am thinking about running some 80# high impedance injectors but I will first try with the stock injectors. I also have a set of turbo injectors and a set from an 944 S. I know that 80# is way overkill but I am also doing this project for trial and error for my buddies race car.

What injectors are you using? do you know what resistors need to be used in order to use stock injectors?

Also what did you do with the AFM? I plan to remove it but not sure were I will mount the IAT.
Old 05-23-2015, 02:59 AM
  #24  
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Originally Posted by jeffro951
Well I am thinking about running some 80# high impedance injectors but I will first try with the stock injectors. I also have a set of turbo injectors and a set from an 944 S. I know that 80# is way overkill but I am also doing this project for trial and error for my buddies race car.

What injectors are you using? do you know what resistors need to be used in order to use stock injectors?

Also what did you do with the AFM? I plan to remove it but not sure were I will mount the IAT.
I steered away from anything over 40# because of tuning issues... our cars won't be able to use over 28# no matter what. I'm looking at these:

http://www.ebay.com/itm/5-YEAR-WARRA...1beba1&vxp=mtr

They're 36# at 3 bar, so if you do the math, about 33# at 2.5 bar when maxed out. They're 12 ohm (high z). I haven't pulled the trigger and have never done this before so I'm curious about what others are running. You definitely need 10 ohm or higher...I don't think stock 951/944S injectors meet that spec unless you add resistor packs or something. Haven't looked too deep into that setup but it's possible.

I'm using a GM 1-bar MAP sensor instead of the AFM. For mounting the IAT I'm still working on it. I made a slick SolidWorks model of a custom piece, but it's going to be expensive to 3D print, so I probably won't do it. It's port matched and just needs to be tapped for 3/8" NPT and have the holes drilled to mount to factory airbox which I was too lazy to implement. If you want the model I'm happy to share it as a file that can be uploaded to a 3D printing service. I made measurements using a factory AFM as a reference. Pics:







I have a good friend offering to weld a bung into a tube for me instead, which I'll probably take up.The other solution is this:

http://www.bellengineering.net/produ...roducts_id=674
Old 05-23-2015, 05:18 AM
  #25  
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I'm thinking of trying the 80# ones because I have them in one of my cars as part of the M-tune kit so I could use them at least to try out. That ebay ad does not clearly state the impedance but other than that not bad price for a set. I have read a lot of stuff on the megasquirts for about 4 years now and I remember someone with a 944 using stock injectors with a couple of resistors so stockers for starters shouldn't be a problem. This car will be a real hack job for me so I'll be trying and changing stuff all the time.
Old 05-24-2015, 02:45 AM
  #26  
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Originally Posted by jeffro951
I'm thinking of trying the 80# ones because I have them in one of my cars as part of the M-tune kit so I could use them at least to try out. That ebay ad does not clearly state the impedance but other than that not bad price for a set. I have read a lot of stuff on the megasquirts for about 4 years now and I remember someone with a 944 using stock injectors with a couple of resistors so stockers for starters shouldn't be a problem. This car will be a real hack job for me so I'll be trying and changing stuff all the time.
I've been using this chart to get impedance data: http://www.polog40.co.uk/article_injector_table.php
Over 10 ohm and you're in the clear unless you want to mess with resistor packs.

I know you're talking about fuel, but what are your plans for spark later on? I'm debating 3 different option with myself and all have pros and cons. LS coils, Ford EDIS-4, or the Bosch direct control COP from an Audi.
Old 05-24-2015, 04:24 AM
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nice resource. I would love to to a COP setup but I already have a ford EDIS setup that should work great with the 944S flywheel.
Old 05-24-2015, 12:50 PM
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It will work but you need to configure it so that it fires every other cycle event. EDIS uses a 36-1 wheel on the crank, and if you have a 62-2, well you see what I mean. There was a guy who ran a 62-2 (I think) spur gear on his camshaft where the distributor used to be and had EDIS running really well on his 924S. I think his username was dean924s, it was a thread on a forum for that sort of thing.

You also will need to have the missing tooth behind the sensor by 90 degrees when the engine is at TDC. Since you have a 62-2, you can have one of the teeth lag by 45 degrees I guess.
Old 05-25-2015, 10:10 AM
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Michael,

Are you going to build the MS around the 2.5 engine and down the road replace the 4 with an 8 cyl? Or just keep the 2.5?

Also, perhaps I missed it, is that noise reduction insulation in the back?
Old 05-25-2015, 02:14 PM
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Originally Posted by Noahs944
Michael,

Are you going to build the MS around the 2.5 engine and down the road replace the 4 with an 8 cyl? Or just keep the 2.5?

Also, perhaps I missed it, is that noise reduction insulation in the back?
Yes, I'm building it for the 2.5 but it won't be hard at all to run a different motor with it. It's a MicroSquirt, so it's pre-assembled. All of the sensors (MAP, IAT, CLT, ignition trigger, WBO2, TPS) are not a problem because you have one per engine regardless of which engine. The only real change would need to be the injector wiring and coils. For a V8 it would make the best sense to fire the banks in wasted spark and batch fire, which is just 30 minutes of harness modification to add wiring and connectors for the new hardware. So bottom line, it's very flexible and can remain in place no matter what engine is installed down the road.

And yeah that's sound deadening in the hatch. I ripped out the old stuff about a year ago because it was trashed and relatively heavy, this stuff is really light and IMO just as effective as the stock deadening. It was $20 for a 15' roll, which was enough to do the hatch and the entire passenger side of the car.


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