@rgolia
my plan now is to work with PBM to source the conversion parts they have developed, adaptors to mount the sensors, obtain the FI ECU(Holley) , and for now will
using the stock intakes and my 50MM TB on the stock plenum.

once ican do all that i will save up to eventually get the ITB from PMB(JenveyHeritage IDF 40//45)

@DRPHIL914

Do you have a link to PMBs Type4 Holley adaptation?

The Terminator X seems to tick alot of the right boxes.

Thanks

no links sorry, they do not have it listed yet , they have not mass produced all the parts yet but this may light a fire under them to do so, but they have a lot going on.

if they don’t have the time or personnel to do that one thought i have is to get all the parts - with eric’s approval, thst they are making , get them scanned so they can be reproduced and start getting some kits together. I will soon have a list/spreadsheet of everything , building this right now and will go from there.
as i get thing ans collect specific part numbers and sources i will post .

Has anybody looked at Simple Digital Systems for aftermarket EFI?

http://www.sdsefi.com/specific.html

Click to view attachment

The kit does not include:
Fuel injectors
Fuel pressure regulator
Fuel rail
Fuel pump
Fuel return line from regulator to fuel tank
Throttle body

George

@GregAmy That was a good read - thanks for taking the time to put it together!
So let me ask you this:
Let's say you already have a 123 distributor with the FI points that you are happy with - could you use one or both of the triggers as a cam/crank position sensor with Microsquirt? The obvious benefit being that you do not have to take the engine out to to fit a trigger wheel (or to change a bad sensor). If possible I think it might really simplify the changeover to Microsquirt and a lot of guys already have them installed.....
Scott

You are most welcome. Did you actually make it through the whole thing?


I don't know a lot of about the 123 or how the factory system triggers the injectors...however, WAG'ing it from the stock DJet computer diagram, I think not.

If I'm reading that diagram correctly, the disty simply provides a "fire now" signal to one of two banks (stock DJet is batch injection) with no logic. Disty triggers open or close like points (or is it Hall Effect?), computer does some electrical magic, and the injectors fire.

Microsquirt (all pretty much all EFI), on the other hand, wants to know where the crankshaft is relative to TDC and from that, and your desired tuning, it calculates timing and fires the injectors; DJet triggers can't provide that, they're a binary signal.

Doesn't mean you can't continue to use the 123 disty and ignition coil if you want to, they'll run fine. But once the MS is installed it's only a few more components to remove the disty (and sell it) and put an EFI-driven coil on it. An EFI-driven coil also which allows you to vary timing based on RPM and load. - GA

I did! It took two sessions only because I didn't have the time to do it in one!

Too bad it won't work, it could have been a great intermediary step.

Ok, to keep the ball rolling, can we also talk about options in general and cost?

Let's consider that all these options need "tuning" to different extents.

For example:

Option 1 - Rebuild D-Jet addressing most common problems/wear items (No ignition)

RockAuto New injectors - $300
Restoration Design New Harness - $480
Jeff Bowlsby MPS Rebuild + basic calibration - $474
Jeff Bowlsby ECU testing - $150
914 Rubber TPS board - $52

Total - $1456

Option 2 - PMB Dual 34 ICT Carbs - $610

Option 3 - PMB Dual 40 IDF Carbs - $1180

Option 4 - DubShop Complete EFI with ignition - $4080

Option 5 - Holley terminator X or similar setup - $1249 as a starting point for the basic hardware...

I consider the DubShop system, the ultimate upgrade but can't justify the cost for a stock or home built 2056 (personal opinion).

I never worked on carbs except for small engines and it's a step back for a stock engine with stock cam.

Rebuilding D-jet seems fairly easy except to fine tune the MPS.

The off the shelf system could be a nightmare or could become plug and play if there is vendor or community support. Final cost is unknown for now and depends how far you exploit the system.

Questions:

A: What is your tipping point $$$ to put D-Jet in a box and start fresh?
B: How much time are you willing to spend to install and setup the system?
C: Which option would you be willing to help a 914 buddy if he offered a bbq dinner and some beer?

Please feel free to add options.

Installing FI is never cheap. People always underestimate the amount of tuning and sorting needed to make even a plug and play system actually run well. Not just cost but time. And plug and play rarely is.
My personal opinion is if you want FI, buy the best system you can, find someone who knows how to tune it and close your eyes when it’s time to swipe the credit card.

No, my non-running engine had the original D-jet, but with lots of questionable components and beat up wires and connectors. I rationalized the price of the Dub Shop kit with guesses how much I could spend to repair the D-jet. Plus I wanted the programability (and the sexy ITB stacks).

I think I am getting more power out of my build, and smoother running. The biggest flaw in the Dub Shop kit is the lack of a separate cold start circuit. Not too important to me, but could be for some.

Last time I looked at this CBPerformance sold complete kits.

Lately I have been looking for EFI on a six cylinder, and the options for generic throttle bodies are many, with adapters for lots of different engines.
Bore size is an option
All the stuff is now out there, including Coil on Plug tech

Rich

@bkrantz

I am seriously looking at the dubshop system. This car is like a family member having it since new, so I will do my best to swipe the credit card with out swallowing to hard. The engine was rebuilt a few years ago at Tangerine Racing, 2056 with new AA heads done by Hoffman. It runs great, but cold and warm starts suck and the fuel smell is getting old. Right now it is running with 44 webers and there is no existing FI stuff left in the car as far as I know.

So is this the place that you started and how much time did it take to install and tune. Please provide details. I can deal with the spend but I cant deal with frustration and not being able to drive the car because I get the thing dialed in.

Like rgolia, I’ve leaned toward DubShop . Mario has a dyno. He seems to provide a reasonable base tune to start from, etc. Sells as a nice complete kit.

I’d really like to know about low speed, off idle drive ability using Alpha-N or hybrid tuning if you know which is being used. Even if you don’t know or haven’t played yet with tuning, what are your impressions of driveability at low throttle?

Regarding cold start circuit, if you mean a Weber type choke circuit, I’m confused. With EFI you should be able to tune injector pulse with by temperature. So if ambient temp (or head temp) is cold, cold, like 20F, you should be able to modify the fuel map and just dump in some extra fuel

I found this thread specifically about the Dub Shop system:

http://www.914world.com/bbs2/index.php?sho...211929&st=0

Almost ten years has gone by!

For all the gory details, check my build thread, from Sept 2021 to Feb 2022. My dyno tune session was July 2022. I was doing other rebuild work at the same time, so my timeline is complicated. I would bet installing just the EFI kit could be done in about 40 hours.

You will need to embrace tuning with Megasquirt software. It takes a bit to get it set up and learn the basics, but the help manual is OK, and there is lots of stuff online. And you need to decide to pursue tuning by trial and error, or spend the money for some hours (3-6) on a dyno with an operator who knows Megsquirt.

Mario was very good to work with. During the set-up for my dyno session, we ran into a problem and Mario responded to my call for help immediately and saved the session.

BTW, I also have Hoffman heads.

Just a quick bump to report a new "find".

Dude pops up on Facebook, in the Porsche 914World group, just bought a 914 and asking "what is this?" with a photo of what looks like an ECU mounted in the rear trunk. I look at it closely and swear that it's a Honda OBD0 ECU. He sends me a closer photo and YEP it's a Honda P06 OBD0 ECU, circa 1993-1995 1.5L Honda del Sol.

He posts a video of the engine compartment and the car is clearly running a Honda disty (with the square bumpout for the coil/ignitor inside) and Honda wiring harness connectors.

It's a blue car, based in Northern California. I suggested to him that he post here but is anyone familar with the car and the engine management design? I'm wondeirng who did it and how.

If you're in that group you should be able to see this...

https://www.facebook.com/groups/40202979983...74386602595671/

That’s wild. Had to have been done in the late 90s by a heavy duty Hondata guy or something. I can’t imagine ever doing something so complicated in the 2000s when MS and a lot of other budget EFI systems really started taking off.

If you read through my build thread, you can see details about the mechanical installation, setting up the fuel lines and wiring, how I mounted the ECU, the pre-start setup (including tune software), the initial start and home tuning, and then my session on a dyno. That all happened over about 6 months (with other build stuff at the same time). I would guess it could all be done in about a month.

Yep, I'm thinking it's a much older build because he says there's no external USB port on the ECU. That indicates it's a socketed EEPROM, well before the Hondata S300 era, so probably late 90s/early 00s. Probably Moates.

I just think it's pretty damned cool that someone went to all that trouble to engineer a D-Jet install to use the (probably) Moates-programmable Honda ECU. I guess when you think about that era, that was about as good as it was for tuneable ECUs...hell, I was doing it with Nissan back then (early 00s) and I thought I was the s**t...that's old school classic rocker stuff; we're not worthy... - GA

That stuff really was ahead of it’s time.

That’s before my time-I would have been in elementary school or middle school when people were really playing with socketed EEPROM. First I’d seen if that stuff was when a buddy bought a modded CRX in high school with a newer motor and S300.

All right young-uns, let me tell you how we used to connect to GENie with a device that made enough noise to get your momma's attention as to why you weren't in bed already...

Definitely "old school". D-Jet (and L-Jet) were so far ahead of their time that full ECU control was, really, still in the future (many don't realize that the mighty 956s Motronic engine management system was a derivative). This came for the fore in the early- to mid-90s with OBD, some systems using pressure (Druck for D-Jet) some using air flow meter (Luft for L-Jet).

Those ECU-controlled cars finally became affordable used cars in the late 90s, and that's when ECU hacking took off. Socketed EEPROMs were the only way to go at the time. You'd find someone to solder in a socket on your board, buy multiple EEPRMs, connect an EEPROM to your computer using an RS232 device, burn the EEPROM. Insert, dyno test. Look at the results, grab another EEPROM to burn with the new tune, swap them, dyno test. Then do it all over again. Tedious.

My first experience with it was in racing with the SR20-equpped Nissan B13s. We weren't even using wideband feedback or data acquisition yet so we'd grab feedback from the driver on where the O2 was down the longest straight and *maybe* take the time to retune the EEPROM, always leaving the weekend's baseline EEPROM off to the side just in case we mucked it up. Even the software was primitive and fidgety to learn. It was right about that time, circa 2005 or so, that guys like CalumSult that tried USB connection and companies like DIYAutotune started offering replacement ECUs (their PnP series) that had USB ports for tuning. Hondata S300. And then eventually wideband feedback, and some times realtime tuning! Life was good.

So I'd really like to meet the guy or gal that did that P06 install into the 914. It was sharp engineering. And I like the way they were thinking! - GA

Back about 15,years ago, I tuned a 2.4 liter to 150 hp, dyno tested at the wheels. I used stock djet.
It turned into a big argument with a certain aircooled engine “expert” who falsely claimed it could never be done.
It can be done.
The MPS and the right resistor in the CHT circuit, along with an 02 sensor to measure results is what is required.
We used a dyno at the end to see how close we got…. But most of the tuning was up and down my street.
Djet runs rich, and can made much richer if required.

After I learned the two basic things to tune, I got almost 50 mpg from a 1.7….
Djet was also used on Volvos and a few others.
I ended up trying all the MPs units from those, we settled back on the 914 one and learned how to tune it.
Best way is with an 02 sensor stuffed up the tail pipe.
I own the djet tester, but it is just a break fix tool.

If I was going to do it again I would use the inline exhaust sensors Foley came up with to measure each exhaust port.


Rich

Not quite 914 FI related but Porsche related. I replaced the CIS on my 78 911 SC with a later 3.2 Carrera manifold and injectors using the injection system from a Nissan 280ZX. I tweeked the barn door AFM and coolant temp sensor to tune the fuel mixture. It worked well. This was in the early 90's with limited affordable aftermarket ECU's. Worked good for years. I eventually replaced it with a FAST programmable system designed for Chevy's. That FAST system from the 90's and the Carrera intake is still running on my friends 911 today.

john

One of the things I'd be wary of with the Dub Shop kit is that it does not (at least when I looked at it) have any ability to run an ICV (Idle Control Valve) or an IAC (Idle Air Control). In my journey with Microsquirt, that's been a critical piece of the puzzle to keep idle steady and starts somewhat smooth.

You CAN do it without the ICV/IAC/whatever you want to call it. For a while I removed the IAC and just used the bleed valve on the TB to manage idle - similar to how D-Jet did it. It works fine once the car is warmed up fully. But getting started on a chilly damp day was challenging that way. And until the engine warmed up it was also a challenging drive, as you need to use throttle to raise idle speed.

Using stock components or using the dual throttle bodies makes the IAC interesting to implement. My solution was kinda janky but it works using a 3d printed connector that attaches a Hyundai IAC from the airbox to the Plenum, suspended on a stout hose. But in my opinion, its a really critical piece of a smooth running FI system. Its also part of the system on just about every modern car.

Zach

Search for a used Ljet system. You can adjust the AFM with the wheel inside.

L-Jet is a good system. But it has some limitations that modern EFI doesn't. L-Jet cannot handle any kind of radical camshaft. The flap in the airflow meter starts oscillating badly due to the cam overlap, and that is detrimental to proper mixture control, and makes the air flow meter wear out rapidly.

That's one of the big reasons that Porsche went from a vane air meter in the 964( like the L-Jet has) to a Mass airflow sensor in the 993. And that's the reason I am going away from the 964 motronic in my car. I have a huge, unresolvable flat spot off idle due to the vane air meter oscillation.

I could have gone to a 993 motronic, but the Megasquirt MS3Pro is actually cheaper and gives me more control over the engine.

@VaccaRabite Zach, I'm controlling idle on my Microsquirt setup using timing advance/retard. Give it 30 seconds of throttle to get the heads warmed up (I'm still working on my cold start up sequence) but then it cores and smooths the idle like a mofo, you'd never know there wasn't an idle air control valve in there.

It's an option within TunerStudio settings and it works really, really well. - GA

There is a German company that does an upgrade to the 964 to use the 993 MAF, cant remember what its called at the moment. One thing I love with a stock system is the no nonsense engine start and idle etc. you have to tinker ALOT to get similar performance with an aftermarket system.

EDIT: got home looked it up. TunerStudio, Startup/Idle, Idle Advance Settings, Change "Idle Advance On" to RPMs. Then Startup/Idle, Idle Advance RPM Settings, and you create a table how you want the timing to change based on RPM.

I have mine set to 15.4@700, 6.7@800, 0@950, -11.9@1100, and -17.9@1250. Cores my idle at 950 really nicely.

Note Startup/Idle, Idle Control, Idle Valve Type is set to "None".

Controlling idle with spark timing is really the way to go in my opinion. It’s pretty prevalent on newer cars (and in the aftermarket most people recommend going this way rather than with an additional IAC setup). It’s similar to how you make sure an AC compressor doesn’t stall a car at idle. I’ve had good success with a timing ‘trough’ controlling idle on some high rev bike race motors, have not done it on a T4 (though sounds like it’s working well for Greg), but it can’t be that much harder since the bike motors have way wilder cams.

Hey Greg! I have no idea what that means.... But I like it!

Seriously, I am looking at Microsquirt for our Healey project. running a Suzuki Swift GTI Twin Cam Engine. The heads have builtin port injection and it runs a MAF system. The MAF (Mass Air Flow) system is bulky and ugly. I have 4 Motorcycle carbs I am starting to set up for throttle bodies only. I think it will look more like a carb'd Lotus engine and run like al modern car.

This is a great thread.

What is everyone running for a fuel pump and what do you think of an intank unit?

In tank is the way to go if you can make it work. Pump stays cool all of the time and you remove an out of tank leak point. My favorite setups for normal engines also have the regulator integrated so you don’t need that external either.

With the ITBs you really need to use timing to control idle…IMO at least.

A lot of the aftermarket injection systems are now running no fuel pressure regulator. Instead, they use a fuel pressure sensor, a solid state relay and pulse width modulation of the fuel pump circuit to regulate the pressure. So no pressure regulator and no return line. The ECU controls the fuel pressure and can increase and decrease it as needed for best efficiency.

I am installing a stepper IAC On my ITB setup. The timing changes can only do so much for the idle control. Think of it as the IAC controls the major idle speed changes. Timing fine tunes it.

Interesting. I'm assuming the timing retard jumps as soon as touch the throttle?

I know the engine Eric is building also uses an IAC, and its currently a sticking point as you can't get the bodies they plug into. I wonder if his team has looked into controlling idle through timing.

@eric_shea

Haven't really noticed; I can send some logs if you'd like to look it over? But note there's also a setting in "Idle Advance Settings" where you control at what TPS and RPM it's affecting timing; mine is "below 2%" and "below 1200". Anything above that and it's using the ignition map.

I'll offer that this feature is giving me some minor headaches on the Toyota MR2 race car with radical cams. The engine either just wants to die near desired idle using low throttle body bypass (not enough air) or take off with more TB bypass (too much air) and there's not a lot of difference between the two TB settings.

I had to find a middle ground where I opened the bypass a tad more and aggressively pulled back timing below 5% TPS to core the idle at 1500 and set it to pull the idle timing below 2500 RPM (which is fine for a race car that lives at 5000-8000). - GA

Impecable timing as to this thread - almost as if Phil was reading my mind.

In discussions with DrPhil this year he had told me about his 50nn throttle body for his D-Jet that he had gotten from Chris Foley when I expressed an interest in finding one for my D-Jet that I hope to install this summer on my 2056 rebuild.

I contacted Chris and he told me he got the 50mm TB here:

http://www.highperformancehouse.com/

from Rich and that it had been custom made with the throttle plate actually hammered out to increase its size.

I checked Rich's website and found this under Porsche:



I never could get an answer at the number but left a message. Over a month later Rich called me.

He explained that the guy who bored out the original TB was no longer around but he did have one 48mm one left that he would let go for no less than $500.00. He also explained how the throttle plate was painstakingly hammered to proper size as Chris had.

$500 for 3mm increase in diameter - no thank you. Made me wonder if a machinist friend could not make one from scratch for that amount from my original 45mm one.

Friends are telling me that my present engine performance with dual IDF-40 EMPI clones is so good that I'd be a fool to go to D-Jet as there is no way it could perform as well. Even cold starts are no problem with 20 seconds of throttle-pumping all that is needed on the coldest days.

I'm going to follow DrPhil's lead on this most likely - depending on his budget. I think his budget flexibility is larger than mine.

I like the idea of using my original D-Jet with a 50mm TB & an AFR gauge which I already have. But if there is a way to get even more power with D-Jet and modern EFI benefits, I'd love to have that - if available at a reasonable cost.

GN

@Gatornapper

another option might be finding the GoWesty 52mm throttle body, not sure if they make them anymore, but Zach had posted on this a few years back and used one i believe on his 2056 , some modification may be necessary.

Phil

@Gatornapper

http://www.914world.com/bbs2/index.php?showtopic=367336

https://gowesty.com/products/gowesty-throttle-valve-housing

says 4 left - these were out of stock and not being made when i got mine from Chris

A healey with a Suzuki motor using custom EFI.
Should be fun to get working!!!

There are places to send a throttle body out, get it bored and a larger butterfly made. $150-250 usually. Just Google it. There’s more than one place to get it done.

In reality, 3mm can make a big difference, as you are increasing the diameter of a circle.
48mm to 51mm would be a 13% increase in area.

I ran one of these on my 2056. It took a minimum amount of modifications to make it work on a 914. On my Microsquirt motor the bigger throttle body opened up a whole new row at the top end of my fueling table. I have the install noted on my build thread for the 2056.

Zach

Thanks Ben - did not know that.

The 50mm (from 45) is a 23.4% increase in area which is what I'd like to see minimal.

I know volumetric flow is determined more by cam & valve size than anything, but when I figure dual 40 IDF's run so well with 3=4 x 40mm there has to be room for more flow than even a 50mm TB would allow.

But I would like to stick with the simplicity of my D-Jet too. and low cost of just replacing the TB with a larger one.

GN