MY CAR’S HISTORY AND THOUGHTS AND QUESTIONS ABOUT MEGASQUIRT
My car is a 1973 1.7 with stock fuel injection that I bought in 2002 and used to drive quite often and for 3-4 years it was my only ride. It was around 2012 that I took it off the road for rust repair and after 2 years on jack stands and a lot of new metal, I got it back together, running and on the ground. I still have a lot to do to make my car nice, but for now the goal is just to have a driver. In the last 2 years I've only driven it briefly (and close to the house) every few weeks due to it running like crap. It won’t idle when cold and spits and sputters while driving but will usually improve after it’s been driven for about 10 mins. I feel like my issue exists in the fuel side and not the ignition. I plan to do a megasquirt conversion in phases due to limited time and I don’t want to drop the motor now. I’m sure some would say why not try and get the original fuel system working properly again and my main answer would be my desire to add boost to this motor in a later phase of this project. That being said, I regret not buying that complete, running 1.7 motor with all its fuel injection components that was in the classifieds a few weeks ago. I assume I could have switched whatever fuel components onto my car and probably be back running again without all this conversion I’m facing doing.
I want to do something like Mcmark did with his megasquirt conversion, which is not modifying my stock 1.7 and eventually adding a small turbo for some extra fun. The first phase would be fuel only due to not having time to drop the motor to do crank fired ignition. The second would be ignition and boost which means motors coming out to install the toothed wheel and sensor and using a small new turbo or a used one from a vw or volvo and I assume some type of intercooler. Luckily, I'm a metalworker and owner of a metal shop so all the metal fab needs that will crop up with a turbo install are no problem. Unfortunately, as a father/husband, a small business owner, a full-time employee at my day job, and the owner of 2 classic cars I have very little time and car projects have had to sit mostly untouched for the past few years. But I’m going to try and carve out some time to get my 914 running reliably again, without tearing it too far down.
THE WAY I THINK I WILL ACCOMPLISH PHASE 1
I plan to purchase the components needed from the dubshop as it seems they have quality parts, and everything needed in 1 place. I would like to retain the stock throttle body and intake. I assume I could remove the original TPS from the throttle body and install a new universal bosch TPS somehow in its place. I also hope to be able to mount new injectors in the stock intake. I'll have to wait until I have the injectors in my hands to know if the diameters of the injector will work with the bore in the intake and if the clamps will hold them in place. If modifications are needed, I’m fairly confident I’ll be able to come up with a way to make whatever changes are required. I believe I’ll be using the Walbro high flow fuel pump but I’m not sure if I’ll need a new relay board that the dubshop sells, although I assume so cause of the new fuel pump. Other than the various sensors required I think that’s it for phase 1 fuel only. Ignition and boost will have to wait unless there’s a way to do ignition without dropping the engine. The final concern I can think of now is tuning, but it seems like with the tuner studio software, this forum, and the dubshop I can get it dialed in.
Parts I think I’ll need for phase 1
1- Megasquirt 2 V3
2- Walbro fuel pump
3- Fuel pressure regulator
4- Fuel filter
5- EV1 fuel injectors
6- Modified coolant temp sensor
7- Intake air temp sensor
8- GM MAP sensor
9- O2 sensor
10- Various weld on bungs for sensors
11- Wiring harness
Questions
1- Does anyone here have any experience with the dubshops products/support?
2- Megasquirt 2 V3(through mount components) or V3.57(surface mount)?
3- Has anyone here tried to mount a modern universal Bosch TPS on original 1.7 throttle body?
4- Will EV1 injectors fit stock intake w/o mods?
5- Do I need a new relay board that the dubshop sells or will the stock 1 work? I assume with the new fuel pump I’d need the new relay board.
6- Walbro fuel pump?
7- Mounting position of modified coolant temp sensor (I assume under #3 cylinder somewhere in air stream)?
8- Mounting position of intake air temp sensor? Does it need to be before or after the throttle body?
9- Mounting position of O2 sensor? I want to keep my heat exchangers and I’m running a Bursch muffler, so I assume it’d be in the muffler tubes where all tubes are merged into 1 tube.
10- Tuning? I don’t even know what to ask here yet, but it worries me.
11- Anything I’m missing for fuel only? And should I be able to expect good results with only doing fuel for now?
Thanks in advance for any advice y’all may have I’ll do my best to keep this thread updated, but like we’ve already established it takes me forever to accomplish car goals. So here’s to getting another 914 back on the road reliably. The flip side of the coin on all this is if I can’t get the 914 running reliably in the next 6-9 months selling it and using the money to get my vw notchback on the road is an option I’m considering. My son is 12 and I don’t have forever to get a classic on the road to enjoy with the family. The Porsche is, of course, only a 2-seater and I have a family of 3. It sucks to think of selling my 914, I have always wanted one since I was a kid in the 80’s. I have been fortunate to own 2 of my favorite cars for a long time now, but sitting in the garage not running reliable makes my wife real happy while having to park her new Jetta outside. For now this isn’t about whether or not I should sell my 914, but I’m not getting any younger either.
Full Version: megasquirt
Consider calling Mark at Original Customs. (McMark here)
He has developed a MSquirt setup for the Type4.
@McMark
He has developed a MSquirt setup for the Type4.
@McMark
As mentioned above, get in touch via PM with the guys that have done it.
Before you contact them start here - get familiar with what they have already done and posted:
http://www.914world.com/bbs2/index.php?sho...256751&st=0
Unless you just like to tinker and not drive your stock motor 914, your time/money is better spent just learning/diagnosing/maintaining the stock Djet FI. Don’t believe me? Go find and read the many stories on this forum for the ‘fun times’ ahead for you with any aftermarket FI.
Just spit-balling here...but how difficult would it be to adapt the @McMark system to a 1.8L?
Background: I'm looking to build a replacement engine for my 2L historics car, broke the crankshaft. But my eye got caught by a rule that I did not know existed, and that's SCCA allowing the 1.8L 914 in H Production, but with fuel injection (no alternate carbs). The primary driving requirement is that it use the stock, unmodified 1.8L throttle body.
I do not want to develop my own fuel injection system. But if I can build a 1.8L engine and adapt something like this to the 1.8L tb, then it may be a viable direction to go. Otherwise I'll just build the 2L Dellorto engine.
Thoughts?
Background: I'm looking to build a replacement engine for my 2L historics car, broke the crankshaft. But my eye got caught by a rule that I did not know existed, and that's SCCA allowing the 1.8L 914 in H Production, but with fuel injection (no alternate carbs). The primary driving requirement is that it use the stock, unmodified 1.8L throttle body.
I do not want to develop my own fuel injection system. But if I can build a 1.8L engine and adapt something like this to the 1.8L tb, then it may be a viable direction to go. Otherwise I'll just build the 2L Dellorto engine.
Thoughts?
1- Does anyone here have any experience with the dubshops products/support?
-Yes, I'm using his ITB's, crank trigger, IAT and CLT sensor, fuel pressure regulator and LS coils.
5- Do I need a new relay board that the dubshop sells or will the stock 1 work? I assume with the new fuel pump I’d need the new relay board.
- I'm not using MS but another EFI system, I'm letting that system control the stock fuel pump relay on the stock relay board. Works fine.
6- Walbro fuel pump?
-Should be fine, I'm using a Bosch 044 copy and its more than enough if a bit on the loud side.
7- Mounting position of modified coolant temp sensor (I assume under #3 cylinder somewhere in air stream)?
You dont want to measure the air temp over the cylinders, the engine tin is a much better choise as its slower to respond to changes. Mine is at the #3 intake mounting bolt.
8- Mounting position of intake air temp sensor? Does it need to be before or after the throttle body?
I'm using ITB's but I'm measuring in the #3/#4 cylinder air filter. In your case directly after the air filter would probably be fine. Yes the air will be alittle warmer going into the cylinders but that will be acounted for in the mapping and its more or less always the same once the engine is up to working temperature.
Feel free to PM if you have any further questions.
-Yes, I'm using his ITB's, crank trigger, IAT and CLT sensor, fuel pressure regulator and LS coils.
5- Do I need a new relay board that the dubshop sells or will the stock 1 work? I assume with the new fuel pump I’d need the new relay board.
- I'm not using MS but another EFI system, I'm letting that system control the stock fuel pump relay on the stock relay board. Works fine.
6- Walbro fuel pump?
-Should be fine, I'm using a Bosch 044 copy and its more than enough if a bit on the loud side.
7- Mounting position of modified coolant temp sensor (I assume under #3 cylinder somewhere in air stream)?
You dont want to measure the air temp over the cylinders, the engine tin is a much better choise as its slower to respond to changes. Mine is at the #3 intake mounting bolt.
8- Mounting position of intake air temp sensor? Does it need to be before or after the throttle body?
I'm using ITB's but I'm measuring in the #3/#4 cylinder air filter. In your case directly after the air filter would probably be fine. Yes the air will be alittle warmer going into the cylinders but that will be acounted for in the mapping and its more or less always the same once the engine is up to working temperature.
Feel free to PM if you have any further questions.
With your time constraints and desire for a more reliable driver you should also consider switching the FI to stock L-Jet. It's a better system than the speed density D-Jet. The fuel is scheduled based on measured intake air as opposed to an inference tied to a given engine configuration of intake, valving, CR, exhaust, etc. For speed density, OEM practice is to map the production configuration so that if you know the manifold pressure you can infer the air flow and schedule the fuel. But if, for example, you change the exhaust system the inference is no longer valid and the fueling can be less accurate. L-Jet is way less sensitive to the engine configuration. I converted my 1.8L from (as found) single carb to L-Jet with a Triad exhaust and later swapped the long block to a 2056. I used all of the same FI parts including the stock injectors and the FI harness that I fabricated. I added an AFR meter to make sure the fueling was correct. It now runs great and has enough zoom for a fun driver. It's also a lower cost option with less tinkering and more driving.
Answers:
1- Does anyone here have any experience with the dubshops products/support?
-Their products are the best and Mario seems like a good dude in my interactions with him. Note that while a lot of the things he sells he designed himself, some of the larger parts (throttle bodies specifically) he resells and may be found cheaper elsewhere.
2- Megasquirt 2 V3(through mount components) or V3.57(surface mount)?
- I would go Microsquirt, its smaller, waterproof, has a better harness connector, and still has way more features than you need
3- Has anyone here tried to mount a modern universal Bosch TPS on original 1.7 throttle body?
-Not sure about "universal but I have used a Bosch TPS from a Volvo (has the correct throttle shaft shape) i dont recall the part number off hand but i have posted about it before. You technically can get by just fine without a TPS though. Its handy to have for flood clear and its nice to see it in your datalogs, but 914s generally are tuned so rich that accell enrichment makes little difference, at least from what i have seen.
4- Will EV1 injectors fit stock intake w/o mods?
-Stock injectors fit the stock intake, you just need to run them with a inline resistors/resistor pack. EV1 injectors are going to require some level of fab work any way you look at them. If you want new, high impedance injectors that are plug and play with the stock intake and fuel rail:
https://www.fiveomotorsport.com/a280-a380-h...-fuel-injector/
5- Do I need a new relay board that the dubshop sells or will the stock 1 work? I assume with the new fuel pump I’d need the new relay board.
You can use the stock relay board, you can also use the stock FI fuel pump
6- Walbro fuel pump?
not sure, whats the part number? output specs? Stock pump is fine with stock injectors, probably fine at higher pressures/aftermarket injectors too but i have not personally tried that. Im running an MSD pump i picked up from summit on one of mine. Lots of bosch options available (Vanagon pumps come to mind) this isnt exactly a high HP application so flow is less of an issue, any pump that can maintain necessary pressure should be good. Thedub shop sells a lot of kits to guys running carbs, hence the need for an aftermarket pump, you already have an FI pump though so i would start there.
7- Mounting position of modified coolant temp sensor (I assume under #3 cylinder somewhere in air stream)?
--Not in the air stream, you are not worried about the air temp, you want your head temp. IF you are using the dubshops sensor you can just mount it using one of the engine tin screws, you will want one that screws directly into a head, preferably near the number 3 cylinder though it doesn't really matter. Megasquirt only uses the head temp sensor for warm up enrichment, and even that is fully tunable so as long as its mounted somewhere that will be representative of when the engine is hot/cold you are fine. Its not like d-jet where the head temp sensor is impacting mixture 100% of the time.
8- Mounting position of intake air temp sensor? Does it need to be before or after the throttle body?
- doesn't matter, doesn't even need to be directly in the intake flow though it should be for the most accurate measurement. If you are running a stock 1.7 intake and filter you could modify the plenum to install it in the stock air temp sensor location (recommend using an open element sensor for sure if you put it there) you could put it in the intake boot, or on the inlet on your air filter. Again as everything is tune-able the slight variation you might see in temp is somewhat irrelevant.
9- Mounting position of O2 sensor? I want to keep my heat exchangers and I’m running a Bursch muffler, so I assume it’d be in the muffler tubes where all tubes are merged into 1 tube.
- anywhere after the 4-1 collector but before the muffler. On the Bursch I usually install the bung on the U turn after the collector on the passenger side. Just be sure to mount it 90 deg or higher angle as you dont want condensation pooling in it.
10- Tuning? I don’t even know what to ask here yet, but it worries me.
-For some people this is a pretty steep learning curve. I highly recommend paying for the full version of tuner studio as its autotune feature when used with a wide-band sensor is amazing. Still requires you know what you are doing as far as AFR targets, but if you are good on theory the rest is easy. I have written a general overview on tuning theory here in the past. If you are going fuel only to start it will be somewhat easier, though less precise as you wont be able to predict your timing 100%. Dialing in a solid strong idle is #1 and very important. Without programmable timing there is less you can do in that regard being at the mercy of your distributor, so it will be a little more art than science figuring out what the engine wants/what works best for idle. Any easy/safe way to start is setting your idle area targets around 13.5 and everywhere else to 12.5. Adjust from there to get the best idle, drive tune to the 12.5 targets, and then lean out the cruise area targets/tune from there as appropriate. Do you have a head temp gauge already? you will want one for piece of mind when tuning.
11- Anything I’m missing for fuel only? And should I be able to expect good results with only doing fuel for now?
-While the most improvements come from programmable digital ignition, running fuel only will run at least (and most likely much better) than your stock d-jet setup. You didnt mention how you are going to acquire your RPM signal though?? While you can pick it up directly off your coil doing that has more of a potential for noise and will require another solution when you eventually go to full ignition control, I would recommend saving yourself the effort of re-wiring down the line and just put in the dubshops type 4 crank trigger from the start. Installation in the car though may be a bit of a pain without dropping the motor.
http://thedubshop.com/type-4-crank-trigger/
1- Does anyone here have any experience with the dubshops products/support?
-Their products are the best and Mario seems like a good dude in my interactions with him. Note that while a lot of the things he sells he designed himself, some of the larger parts (throttle bodies specifically) he resells and may be found cheaper elsewhere.
2- Megasquirt 2 V3(through mount components) or V3.57(surface mount)?
- I would go Microsquirt, its smaller, waterproof, has a better harness connector, and still has way more features than you need
3- Has anyone here tried to mount a modern universal Bosch TPS on original 1.7 throttle body?
-Not sure about "universal but I have used a Bosch TPS from a Volvo (has the correct throttle shaft shape) i dont recall the part number off hand but i have posted about it before. You technically can get by just fine without a TPS though. Its handy to have for flood clear and its nice to see it in your datalogs, but 914s generally are tuned so rich that accell enrichment makes little difference, at least from what i have seen.
4- Will EV1 injectors fit stock intake w/o mods?
-Stock injectors fit the stock intake, you just need to run them with a inline resistors/resistor pack. EV1 injectors are going to require some level of fab work any way you look at them. If you want new, high impedance injectors that are plug and play with the stock intake and fuel rail:
https://www.fiveomotorsport.com/a280-a380-h...-fuel-injector/
5- Do I need a new relay board that the dubshop sells or will the stock 1 work? I assume with the new fuel pump I’d need the new relay board.
You can use the stock relay board, you can also use the stock FI fuel pump
6- Walbro fuel pump?
not sure, whats the part number? output specs? Stock pump is fine with stock injectors, probably fine at higher pressures/aftermarket injectors too but i have not personally tried that. Im running an MSD pump i picked up from summit on one of mine. Lots of bosch options available (Vanagon pumps come to mind) this isnt exactly a high HP application so flow is less of an issue, any pump that can maintain necessary pressure should be good. Thedub shop sells a lot of kits to guys running carbs, hence the need for an aftermarket pump, you already have an FI pump though so i would start there.
7- Mounting position of modified coolant temp sensor (I assume under #3 cylinder somewhere in air stream)?
--Not in the air stream, you are not worried about the air temp, you want your head temp. IF you are using the dubshops sensor you can just mount it using one of the engine tin screws, you will want one that screws directly into a head, preferably near the number 3 cylinder though it doesn't really matter. Megasquirt only uses the head temp sensor for warm up enrichment, and even that is fully tunable so as long as its mounted somewhere that will be representative of when the engine is hot/cold you are fine. Its not like d-jet where the head temp sensor is impacting mixture 100% of the time.
8- Mounting position of intake air temp sensor? Does it need to be before or after the throttle body?
- doesn't matter, doesn't even need to be directly in the intake flow though it should be for the most accurate measurement. If you are running a stock 1.7 intake and filter you could modify the plenum to install it in the stock air temp sensor location (recommend using an open element sensor for sure if you put it there) you could put it in the intake boot, or on the inlet on your air filter. Again as everything is tune-able the slight variation you might see in temp is somewhat irrelevant.
9- Mounting position of O2 sensor? I want to keep my heat exchangers and I’m running a Bursch muffler, so I assume it’d be in the muffler tubes where all tubes are merged into 1 tube.
- anywhere after the 4-1 collector but before the muffler. On the Bursch I usually install the bung on the U turn after the collector on the passenger side. Just be sure to mount it 90 deg or higher angle as you dont want condensation pooling in it.
10- Tuning? I don’t even know what to ask here yet, but it worries me.
-For some people this is a pretty steep learning curve. I highly recommend paying for the full version of tuner studio as its autotune feature when used with a wide-band sensor is amazing. Still requires you know what you are doing as far as AFR targets, but if you are good on theory the rest is easy. I have written a general overview on tuning theory here in the past. If you are going fuel only to start it will be somewhat easier, though less precise as you wont be able to predict your timing 100%. Dialing in a solid strong idle is #1 and very important. Without programmable timing there is less you can do in that regard being at the mercy of your distributor, so it will be a little more art than science figuring out what the engine wants/what works best for idle. Any easy/safe way to start is setting your idle area targets around 13.5 and everywhere else to 12.5. Adjust from there to get the best idle, drive tune to the 12.5 targets, and then lean out the cruise area targets/tune from there as appropriate. Do you have a head temp gauge already? you will want one for piece of mind when tuning.
11- Anything I’m missing for fuel only? And should I be able to expect good results with only doing fuel for now?
-While the most improvements come from programmable digital ignition, running fuel only will run at least (and most likely much better) than your stock d-jet setup. You didnt mention how you are going to acquire your RPM signal though?? While you can pick it up directly off your coil doing that has more of a potential for noise and will require another solution when you eventually go to full ignition control, I would recommend saving yourself the effort of re-wiring down the line and just put in the dubshops type 4 crank trigger from the start. Installation in the car though may be a bit of a pain without dropping the motor.
http://thedubshop.com/type-4-crank-trigger/
Subscribing.
I have a mostly-perfectly-functioning 2L D-Jet system, but I don't trust it. It seems to work great at times, but every now and then - usually when I'm an hour away from home - it'll have this massive burp and run bad for a bit. Makes me nervous. And it seems to be extremely sensitive to fuel selection; a couple times it flat-out did not like the fuel I got from specific, common, high-volume stations.
I removed the street car drivetrain for some basic maintenance (seals, clutch, etc) and was amazed at how cluttered the engine compartment is with the D-Jet stuff. Wiring, hoses, components. Would be nice to clean all that up.
Finally, I'm also giving thought to prepping the orange race car to SCCA "Limited Prep" regs, which requires the use of the stock throttle body. So this may be a good time to try it on the non-racer and learn something.
I PM'd and emailed McMark, no response. So I think I'll just forge forward. I'm not quite sure how I'm going to proceed, but back-of-the-napkin makes me think it can be done for less than $1500 in components. I'd look to retain as much stock componentry as possible, including throttle body and intake, fuel pump and regulator, stock injectors (clearly they flow enough for the stock engine) and fuel lines. Generally speaking, I'd replace the stock ECU and wiring harnesses, distributor and wires (for coil packs), add crank trigger and sensors, and add a wideband.
Let's keep in touch and compare experiences, see if we can make this an easy install. More later.
I have a mostly-perfectly-functioning 2L D-Jet system, but I don't trust it. It seems to work great at times, but every now and then - usually when I'm an hour away from home - it'll have this massive burp and run bad for a bit. Makes me nervous. And it seems to be extremely sensitive to fuel selection; a couple times it flat-out did not like the fuel I got from specific, common, high-volume stations.
I removed the street car drivetrain for some basic maintenance (seals, clutch, etc) and was amazed at how cluttered the engine compartment is with the D-Jet stuff. Wiring, hoses, components. Would be nice to clean all that up.
Finally, I'm also giving thought to prepping the orange race car to SCCA "Limited Prep" regs, which requires the use of the stock throttle body. So this may be a good time to try it on the non-racer and learn something.
I PM'd and emailed McMark, no response. So I think I'll just forge forward. I'm not quite sure how I'm going to proceed, but back-of-the-napkin makes me think it can be done for less than $1500 in components. I'd look to retain as much stock componentry as possible, including throttle body and intake, fuel pump and regulator, stock injectors (clearly they flow enough for the stock engine) and fuel lines. Generally speaking, I'd replace the stock ECU and wiring harnesses, distributor and wires (for coil packs), add crank trigger and sensors, and add a wideband.
Let's keep in touch and compare experiences, see if we can make this an easy install. More later.
SDS EFI I've installed and tuned a 2.0 fuel only system in one weekend.
Web #73 stock 2.0 engine using most of the stock Djet intake including the injectors and using an 1.8 dizzy.
I've used my SDS EM-4F, that I bought in 2004. in stock 1.8 and 2.0 engines in my 914. The same system has been updated (chip) and now resides in my summer DD 2600cc, 102 x 78mm, T4 in my '67 VW bug.
I might update it to EM5 spec and put it in the wife's new 914, but for now I'm going to put a 1.7 I have in it to see if I can get the Djet to work.
Web #73 stock 2.0 engine using most of the stock Djet intake including the injectors and using an 1.8 dizzy.
I've used my SDS EM-4F, that I bought in 2004. in stock 1.8 and 2.0 engines in my 914. The same system has been updated (chip) and now resides in my summer DD 2600cc, 102 x 78mm, T4 in my '67 VW bug.
I might update it to EM5 spec and put it in the wife's new 914, but for now I'm going to put a 1.7 I have in it to see if I can get the Djet to work.
Fuel-only is perfectly fine for what we're doing. Hell, even moreso on the race car, where I'm at full-advance all the time, no nuance needed.
Got a parts list for your SDS system? I've sent them a couple notes looking for more info, no response...
I'm also thinking a simple Microsquirt system would work fine as well. Something that will take a crank position off a toothed gear, combine it with RPM, MAP, TPS, and temperature, and output simple batch firing.
It's really not unreachable technology, given today's tools. It's certainly no more difficult than what I've done with Calumsult (Nissan) and/or Hondata. I even got comfy with the Megasquirt setup when I assisted Chris Foley getting one running in his shop.
Got a parts list for your SDS system? I've sent them a couple notes looking for more info, no response...
I'm also thinking a simple Microsquirt system would work fine as well. Something that will take a crank position off a toothed gear, combine it with RPM, MAP, TPS, and temperature, and output simple batch firing.
It's really not unreachable technology, given today's tools. It's certainly no more difficult than what I've done with Calumsult (Nissan) and/or Hondata. I even got comfy with the Megasquirt setup when I assisted Chris Foley getting one running in his shop.
QUOTE(GregAmy @ Dec 8 2019, 05:15 PM) 
Fuel-only is perfectly fine for what we're doing. Hell, even moreso on the race car, where I'm at full-advance all the time, no nuance needed.
Got a parts list for your SDS system? I've sent them a couple notes looking for more info, no response...
I'm also thinking a simple Microsquirt system would work fine as well. Something that will take a crank position off a toothed gear, combine it with RPM, MAP, TPS, and temperature, and output simple batch firing.
It's really not unreachable technology, given today's tools. It's certainly no more difficult than what I've done with Calumsult (Nissan) and/or Hondata. I even got comfy with the Megasquirt setup when I assisted Chris Foley getting one running in his shop.
I wrote out a long answer, then it got wiped out for some reason. Not rewriting it .... if you want to talk about SDS PM me and I could call you as I have unlimited calling.
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