After reading and reading some more, I finally decided a few months ago to challenge myself with a Microsquirt conversion. Many members here were very inspirational. I want to thank the ones who have shared their builds and issues as they are very helpful. I hope my build can contribute to others and add to this wealth of information. I'm also aware that I might run into issues but that is part of the process.
First, a little background. A few years back I rebuilt my 2.0 due to a spun rod bearing on my last run of my first DE event with POC at Streets of Willows. While this was an unpleasant outcome, the day still remains a fantastic moment with my 914. I did the rebuild myself with all of the valuable information here.
I like to think that I did things right and the outcome is a fun 2056 with mild cam, D-Jet oblige, that I have enjoyed commuting with for many years and took along the coast all the way to Monterey four times, two of which were to attend the amazing Rennsport Reunion V and VI.
One of the reasons I want to upgrade to a modern FI system is to be able to better tune the engine which is limited on the D-Jet, especially when engine displacement is increased as we know. This is the first step in my ultimate build which would be a 78x96 stroker engine. But that will be later.
So here we go!
I bought my Microsquirt and crank trigger sensor sensor setup from Mario at the Dubshop. I like the way the trigger is engineered and it allows the installation of remote oil plumbing (full-er flow setup).
Being on a very tight budget (I know this doesn't rimes with 914 anymore) I bought all my new individual components from ebay with matching pigtail connectors to build my own harness.
VW waste spark coil pack
GM 1 bar MAP sensor
Hyundai (and others) TPS
BMW ICV
BMW air cooled motorcycle CHT sensor (used). Same M10 thread as the D-Jet CHT.
I will be reusing:
Stock green injectors, with additional resistors
Stock IAT sensor
I also bought new connectors and crimp terminals and boots for all reused stock components.
To begin the build, I elected to prepare a development harness with extra wire length and build a bread board setup. This will allow me to make sure that all components are functioning. Once the engine is running, I will rebuild the harness with the proper wire length and sleeves to ensure a clean and reliable installation.
Enough writing... On with what people want! Pictures
Bread Board setup:
1 Bar GM MAP Sensor:
Resistance pack for low impedance green stock injectors. The resistances are not needed if you use modern high impedance injectors.
Used BMW Motorcycle Cylinder Head Temp sensor with M10 thread which will screw in the stock 2.0 head CHT location.
Throttle position switch compatible with the stock 914 throttle body with its 8mm D shape shaft.
Stock intake air temp sensor with new crimp and connector:
The resistors, as per delivered directly from China, were not up to my standards as far as surface for thermal management. The aluminum mounting plate will act as supplementary cooling. So I sanded their base on a flat surface. I will use thermal paste between the resistors and aluminum mounting plate to ensure good thermal conductivity.
Before:
After:
looking sweet so far.
Here I am calibrating the intake air temp sensor. MS requires 3 data points to establish the sensor curve.
Easy way to do this:
Room temperature resistance
Boiling water resistance
Cold water resistance.
Using a K type thermocouple and a reader, I positionned the TC tip next to the sensor in the water (same depth). Interesting to see how the water isn't reaching the 100C mark at that level in the pot, even after a few minutes.
Same process for the cold water.
Same process was repeated with the BMW motorcycle CHT. Well, you get the idea...
Curious, are you using the Dubshop Individual Throttle Bodies too or are you modifying to work with the stock plenum and runners?
That Dubshop ITB setup looks very promising but I have only seen one YouTube video of it on a 914 but it seemed to run nice.
Moving on to the TPS bracket. As mentioned before, the TPS fits properly on the throttle body 8mm D shaped shaft, but it needs to be at the right angle, also the TB shaft is a little long.
So the bracket also needs to act as a spacer. One way around that could be to cut the butterfly shaft but I didn't want to do that. Another way would be to drill a hole in the TPS so that the shaft went through it. By design, the TPS is sealed, and I didn't want to change that, so no hole.
Looking at the TPS, it was designed to be mounted on a flat surface, centered in a bore and sealed with the green O-ring.
I started taking measurement and designing the bracket. Then using my Bridgeport milling machine , I meant hack saw, step drill, HF hand drill and my trusted file, I prepared the bracket.
Luckily the step drill was the right dimension to center the TPS and offer the right surface for the o-ring to seal
I installed the bracket on my mockup spare TB then push on the TPS centered on the bore. Holding the TPS, I opened and closed the butterfly to ensure the TPS had enough travel and was not reaching its limits before the butterfly did. Everything checked out good and there was even room for more travel. I centered the backlash of the TPS over the butterfly travel and mark my bracket to make the TPS mounting holes. Once tapped, the bracket was ready and fitted with metric screws.
Here is a snapshot of my Excel spreadsheet. I obviously have all the receipts from my various purchases and will gladly share them if someone would like more info.
95% of what is being said here is beyond my apprehension, but I totally love it. And its completely in the 914 spirit.
I can only dream about FI (not liking my carbs).
Good luck with this, and please keep the thread updated.
PM sent
What is the source/application of that TPS? And will that installation clear the stock air filter assembly?
Really interested in following this as I have a customer 2L car here that may get Microsquirt as part of the engine upgrade.
Another thing i should add.... Before you get to far you may want to consider adding a 2nd MAP sensor to your build for real time barometric correction. Its a minor addition but you are going to want it if you ever head up any passes.
Also, didnt see it mentioned anywhere in your list but you are going to want a Wideband O2 sensor in there as well. Its false economy to not have one.
I will try to answer all the questions but before I would like to say that I am flattered by the interest and the comments shared by the knowledgeable and highly respected members here.
I will try to do this in order...
@http://www.914world.com/bbs2/index.php?showuser=15565 : Source eBay, Bosch knockoff used on Volvo, Saab, Porsche. P/N GEGT610131, $13.34 including the pigtail connector.
Clearance with air filter, a picture = 1000 words
@MarkHenry: (Don't remember how to ping someone with the @ and space in username...) This is all I have purchased so far. The rest, I had accumulated over the years (wires, transformer for breadboard setup). I also already have an AFR gauge on the car that I will reuse.
@http://www.914world.com/bbs2/index.php?showuser=104 :
It would be very difficult to track time because I have been reading about MS conversion for about 2-3 years and I will still need to read more as I go along. For me, this is not about time spent, it's about the journey...
@http://www.914world.com/bbs2/index.php?showuser=5834 :
Thank you for commenting, I highly value your input on the MS.
Based on what you said, I will not use the ICV in the beginning. check.
I will order a second MAP immediately. check.
I already have an AEM wideband O2 sensor that I bought and installed when I built my 2056. Since I have SS heat exchangers and a banana muffler, its location is far from ideal. It's in the tailpipe as close to the muffler as possible...
Merry Christmas everyone
Personal design notes on the TPS bracket design.
Took a few minutes today to prepare the tool to install the BMW Cylinder head temp sensor.
I got a 14mm long reach socket from my local FLAPS and made a slot with my thin disk grinder and Dremel tool. This will allow the wire to go through as shown in the second
picture.
Then I tried it on the cylinder head. You can also see my ring style type K thermocouple under the #3 spark plug for my cylinder head temperature gauge. Note that this CHT gauge is separate from the whole MS installation. I installed it upon my engine rebuild about 6 years ago for monitoring.
Just came back from a short trip and this was waiting for me.
Per @http://www.914world.com/bbs2/index.php?showuser=5834 recommendations, I got a second GM style 1 bar MAP sensor for the atmospheric pressure monitoring. Amazing to get this delivered to your door in a couple of days for $9.35 all included
I guess I will connect this one to the analog input of the system but haven't looked yet. Hopefully, there will be a selection for this MAP sensor.
Hi, Could you possibly share the amazon link?
Thanks
I had a few hours yesterday and today to work on a combined coil and MAP bracket.
Since the Distributor will be gone, this combo will be located in that area and the bracket will be secured using the 8mm bolt of the distributor bracket and a couple of engine tin screws of the right side cylinder tin.
It will obviously get painted once I am 100% everything fits. Hardware is metric to be consistent...
Busy weekend! Took the family to JPL's open doors yesterday to check out the Mars Rover before it leaves for Florida for the launch.
Today I prepared a bracket for the ICV. Even though I don't intend to connect it initially (per JamesM recommendation ), I will eventually.
I got the aftermarket BMW rubber mount and used an aluminum plate to make a bracket that will mount on the M6 coil mounting points on the cooling tin.
I also got a couple of BMW elbow tubes that connects to the ICV so they match the ports. The brass fitting are residential PEX tubing adaptor elbow 3/4 to 1/2. They happen to fit perfectly in the BMW hose and the 914 vacuum hose. shown in the picture is a small length of the 914 hose to validate. I intend to use hose clamps to avoid vacuum leaks.
This setup will allow me to use the stock ports on the air filter and intake plenum.
Last, the setup temporarily mounted on the cooling tin in the location where the coil usually goes.
Next step; oil pump
Yes, the"while in there" kicked in and I am revisiting my external oil cooler/thermostat/oil filter setup...
BMW mount and rubber elbows tubes? from Where?
Sorry for all the inquiries.
I purchased a Microsquirt as well and will be trying to modernize my 1.7 I hope
Thank you
Ted
Amazon and Ebay are usually my first go to places.
In this case, all of the following parts are from Amazon:
I was told or I read that a resistor like this needs to go on one of the negative wires of the ICV. I think it's the closing wire. To be looked into when connecting it...
This tube adaptor will allow me to connect the GM MAP using a short length of 1/4 vacuum tube from a FLAP to the stock size vacuum hose for the stock MAP in the stock connection point in the plenum.
Liking this, although I also struggle to understand the electronics of it. doesn't hurt to learn something new.
I'm guessing that with a system such as this, your cam choices would be expanded beyond the usual d-jet compatible cams. How much cam and head work would a system like this take?
I understand you are wanting to use the d-jet pieces you have on hand. but could this work with the large bus plenum and throttle body? supposedly it has better flow characteristics than the 2.0 plenum. Just thinking out loud here...
A little more work done this weekend.
First, Friday ( I get every second Friday off ) I went to EMW and got my oil pump blocked off. They pressed a slug in the hole. It felt like it was protruding a little over the pump diameter so I gently filed it down and checked the diameter once done. It is now ready for the re-installation. I'm hoping to get a cast iron full flow pump cover with pressure relief from Gene Berg maybe tomorrow if they are open.
Then I fabricated a block off plate for the oil filter mount that I am removing. I used a 1/4" aluminum plate and my trusted hack saw, vise, file and HF drill...
While I was at it making blanks, I also did one for the plenum as I will not be using the stock Cold Start Valve (CSV) anymore.
Next steps ahead, oil pump and cover installation, and Dub Shop crank trigger setup.
Friday I received my 914 Rubber order of various reassembly part needed for the project. The trailing group buy bushings are for later but I couldn't pass on these.
I will add the project related items to my spreadsheet which keeps on climbing .
I spent some time in the garage yesterday and achieved a little more work on the project. Most of it was on the "while I am in there"...
I removed the crankshaft seal and replaced it with a new one I had in my stock of parts. I also took the time to polish the impeller hub on the seal contact surface before reinstalling it, then torqued the bolt to 23 ft-lb as per spec. I used a steel plate I had laying around to prevent the hub from rotating while i was torquing.
Before looking into the crank trigger installation, I revisited the sequence of assembly for all of the oil related components I needed to reinstall.
First, the filter mount block off needs to go on. So I prepared a gasket for it and installed it.
Then I removed the top oil galley plug since this is where my oil will feed the engine after going through the remote filter and cooler loop. Luckily, the 8mm Allen socket fits perfectly in the 3/8NPT plug as 5/16" and 8mm are very close.
Then, I reinstalled the stock oil cooler in place. I have been debating about removing the cooler to allow more cooling to that cylinder bank as per Chris Foley's modification but I will keep that for when I rebuild my engine into a 2.3 stroker. Sorry no picture for that step but you get the idea...
Finally, I did a dry run of the crank trigger wheel installation to see how this fits. The Dub Shop parts fit very nicely, and as you can see will not interfere with any of my oil plumbing modifications.
That's it for this weekend's work. Next steps ahead, finish the oil plumbing modifications and preparing the crank trigger final installation which will launch the reassembly of FI system.
A busy (non project related) month has passed already so it's time for me to post some of the updates on the work.
Although I have looked into ways of making the elbow feeding the oil back to the engine one that would have a nice sweep, I didn't come up with any good options. Anyway, I got what I believe to be a forged brass 3/8NPT elbow but the inner passage was not to my liking. The inner sharp corner that results from the machining of the ID from both side was so thin that is was already chipping. Clearly, it had to be massaged
Before:
After: This should help to flow around this corner. Not only the passage was increased in size but the inner corner was rounded as much as I could with my various Dremel bits.
On to installation... The first dry run showed that there might be interference between the elbow and the engine block, so I did a little filing to ensure proper fit.
Final clocking:
Moving on to the oil pump. My pump is a Type 1 Schadek 30mm, which is considered to be on the larger scale for the type 4 engine. That is why I went with @http://www.914world.com/bbs2/index.php?showuser=26 recommendation to use the Gene Berg pressure relief full flow cover.
The issue with using a full flow cover is that the oil line (outlet) interfere's with the passenger side engine mount. There are different options to go around that. In my case, I decided that, for now, I would remove part of one of the two gussets, although this is not ideal.
It is also a well know fact that elbows in fluid dynamics are pressure loss points. Ideally, one would use sweep elbow like the -AN tube style.
After looking at the various pictures of existing setups documented here, I decided to go with a 45deg 3/8NPT male to 10AN male fitting on the pump cover. Then, my Parker Push-Lok 5/8" ID hose would terminate on a 45 degree sweep elbow 10AN female to mate to the cover fitting. This is helps reduce the pressure loss and minimize the modifications done to the engine mount.
Enough talking... on with what people want! Pictures
Gene Berg pressure relief full flow cover with AN 45deg elbow:
Clocking of the fitting for clearance issues:
Backside view of the cover where we can see how its design feeds nicely into the outlet port. The other small hole is actually the pressure bypass that feeds back into the pump. Simple.
So now that we have this, what is the required clearance needed to the engine mount for all this to work. After a lot of back and forth and removing small portion at a time I came up with this shape to the mount.
After sanding and rattle can paint:
Coming up, engine mount and pump re-installation...
For the oil pump installation, I read here that Permatex sealant 80019 is recommended for this task. Paper gasket and gently pushed into place.
Since I want to do a final validation of the various clearances between the blue AN elbow on the pump cover, the engine mount, the mount upper bolt head, and the mating AN female fitting, I used the pump cover without any gasket or sealant and torqued down the nuts to set the pump itself.
About a week later, I removed the nuts on the cover and began the clearance validation... There was a small interference between the blue elbow and the upper mount bolt so I filed away some of the fitting boss that is used for tightening it in place. Luckily not much was needed.
First try, almost there:
End result on the fitting
Here is the clearance between the blue elbow and the engine mount:
And here is everything including the rubber mount stud and mating female AN fitting.
This setup will work but I am not 100% pleased with the outcome as it is a tight squeeze. There are better ways for achieving this. Mark Henry's engine mount modification and straight out fitting at the cover is more elegant. It requires more fabrication on the mount but it is much cleaner. McMark also has a version where he modifies the pump cover to have the outlet on the face instead of the side. With a 90 deg elbow screwed on the face of the cover, everything is cleared. This requires a cover with sufficient thickness to have enough thread engagement.
I finished preparing the Hall sensor by twisting the 3 wires and putting a heat shrink sleeve. I also slid over a rubber grommet that will go in the opening if the engine tin.
Installing the bracket for the Hall effect crank trigger I noticed the engine block has a small counter bore on the lower bolt of the crankshaft seal. I used a thin washer so that the bracket sits on a flat face, not a void.
Before bracket installation:
With crank sensor bracket on. We can't see it but there is a washer hidden between the block and the bracket
I adjusted the distance between the sensor face and the backside of the 36-1 toothed wheel to 2.1mm. Recommendation is less than 3mm.
Last step for the day, I removed the distributor drive and installed the distributor plug. Here there are a few options available. I chose this one because of its design. The long center set screw actually pushes outward the bottom of the plug cut in 4 segments. This should prevent the plug from popping out.
Well it has been a month since my last post, time to give a little update on my project.
I should try to edit the title and add "Full Flow and also Fuel Pump Relocation" ... need to figure out how to do this though...
Moving on to the driver side engine mount. The large socket head cap screw sticking out of the Gene Berg oil pump cover is holding the pressure relief spring. This head comes in conflict with the engine mount. So this side too need to be modified...
After modification and paint:
Mount installed and oil pump reassembly process. Assembly lube on the gears and ready to close it up:
Gooped paper thin gasket:
Final pump assembly with the two modified engine mounts, nice milestone
Next step, prepare the oil lines that need to be installed before the fan housing goes back on. To prepare the lines I needed to establish their length.
The lines will be connected to the remote filter - H type oil thermostat panel.
First, using aluminum parts I had, and my trusted hack saw, HF drill and file, I prepared this integrated setup that will be mounted on the passenger side lower firewall. You can see the remote oil filter mount and H-type oil thermostat.
The 2 blue AN-10 fittings on the right are for the lines coming from and going to the engine. Note that this oil filter mount can be used in various configurations. In this case, you can see that one port is plugged on each side (silver plug). Arrows allow to see the flow path.
Oil flow; Oil is siphoned from the engine case by the oil pump. Pump pushes the oil out of the engine via the pump cover, and feeds the remote oil filter. From the filter, oil goes to the thermostat. If the oil is below 180F, the thermostat is closed and the oil goes back to the engine (thermostat upper right port). At about 180F, the thermostat opens and the oil is routed to the external oil cooler via the thermostat lower left port and loops back to the thermostat upper left port then through it and back to the engine.
Moving on...
After taking a few reference measurement I did a quick mock-up of the setup to define the actual length of the oil lines linking the engine to the filter/thermostat panel,
Whit this in place, I was able to prepare the oil lines. I am using Parker Push-Lok high temperature 836-10 blue hose. The 10 is for 5/8" (as in 10/16") and will be a perfect fit for my aluminum AN-10 push-on fittings.
And Voilà! just like that a couple of lines installed!
We are now ready to move on to the reassembly of the engine tin, fan housing and fan.
Eric, maybe I missed it above, but are you leaving the stock cooler in place? On my race car (uses a CB Performance dry sump pump), Chris Foley built a block that replaces the cooler and routes the oil straight back in, allow me to remove the cooler, factory flaps/controls, and put a piece of sheet metal where the cooler was to flow more air to that side.
Leaving it in is fine but I like the concept of removing the factory cooling flaps and one more item that could fail (the cooler, though it's rare for it to fail).
I did some good progress recently with all of this time staying home.
Before installing the engine tin back on, I made a small modification to the cylinder 3-4 tin to fit the crank trigger sensor wire grommet. Here you can see the U shaped opening that I will create. As a reference, the large round hole is for the oil pressure sensor grommet.
And the test fit of the grommet.
Then I installed all of the engine tin back on and replaced the belt too.
Here you can see the distributor plug, the the oil pressure boot (914 Rubber) and my HF grease gun high pressure hose for remote oil pressure sender. Also, you can see the crank trigger wire safely installed.
Many new things in this next picture. First, the coil mount fabricated earlier in the thread got painted and installed using the distributor clamp M8 thread in the engine block and the cylinder 3-4 tin 2 mounting screws. The bracket was designed to support the modern VW coil the way it is meant to be, resting on the three mounting points, not on its base. It also supports the MAP sensor seen below the coil. You can also see the rubber vacuum line connected to the MAP sensor. This 6mm hose connects to the standard 914 8mm hose with an aluminum step up barb fitting. You can see the other end of the MAP hose where it has become the standard 8mm hose and connects to the stock location on the plenum.
Aluminum step up barb fitting and hose transition.
Intake runners and stock green injectors reinstalled with fresh o-rings.
Next, I upgraded my Magnecore 8.5mm ignition wires so they could be used with the new VW coil. I ordered LS style terminals and the crimping tool. These next pictures show the various steps involved in this modification. Hopefully, they will work properly...
First, I pulled of the distributor end boot.
Then removed the crimped terminal...
And here we have the wire ready to receive its new terminal.
Using the MSD crimping tool, the new terminal can be crimped on with a wise. Don't forget to slide on the boot first though.
Here is the finished result.
With these ready, they can be installed on the engine.
Digging the MSD crimping tool and results. I hadn't seen that before. Pretty slick.
Good write up! I am hoping there is an update.
Good work!
Some peeps question (get mad) why my billed labour gets so high for custom work...this is why, custom work is a beyond major time suck.
This is some beautiful work.
If I might make a suggestion..... Use the injectors from a 1980 Datsun/Nissan 280ZX. The impedance on them matches the modern FI better than the D-Jet injectors, and the are sized right for a 2.0L motor. And they are way easier to find than a D-Jet injector. Sell the D-Jet injectors to someone running stock D-Jet.
Clay
He already has it set up as low impedance, I wouldn't change that. I've run an 1.8, 2.0 and a 2.0 with a SCAT C-25 cam on 2.0 Djet injectors with great success.
Hi or low impedance injectors I don't think there's any consensus of one being better than the other, just with high impedance you don't have to use a resistor pack and they are more common now.
Speaking of the resistor pack, make sure it's isolated as it can get hot with long periods of WOT. Not a big deal, you just don't want things like wire and plastic laying on it.
I am going to post this here as it is pretty thorough microsquirt build.
https://tgadrivel.blogspot.com/2020/03/on-microsquirting-porsche-914-part-1.html
If you dont want it here @http://www.914world.com/bbs2/index.php?showuser=15565 I will delete it
Just watch your injector duty cycles, at WOT you want no less than say 25% and no more than 80%. Low impedance injectors will work in this wide duty cycle range.
Dp
What are NOS injectors worth?
Thank you for these recent posts!
Yes I am looking forward to going back to the MS project. Unfortunately, with the power train out, I had the great idea of getting my car painted . Obviously, this leads to making sure the rusted areas have been taken care of...
This (link below) is why I temporarily stopped the MS project!
http://www.914world.com/bbs2/index.php?showtopic=349463
The intent is that while the car will get painted i can get back to the engine and make progress.
But first, let me answer a few questions:
- Clay, thank you for the info on the Datsun injectors, noted.
- Yes, I also have the information from Greg as we have been chatting a lot on this.
- And yes Mark, you are right on the spot, this is a limited budget venture, if this actually exists.
I will definitely document the rest of the work, just like I am documenting my body work thread.
But mostly, I really miss driving my little car...
Powered by Invision Power Board (http://www.invisionboard.com)
© Invision Power Services (http://www.invisionpower.com)