What modern EFI systems is everyone installing on their Type-IV engine?

I'm putting a MS3X (Megasquirt) on my 2.0L. Non T-IV, but my 2.5LGT motor is getting a Syvecs S8.

May people have used MS1/2 and Microsquirt on with good success. They are really quite capable systems for the money, and far sophisticated enough to run a simple motor. The Microsquirt especially (not as much capability, but fully sealed with better connectors) is pretty well suited for this application.

The $5k your mechanic quoted you for a MoTeC system could be quite the deal (wonder which ECU?), albeit expensive compared to an MS conversion, since the MoTeC hardware is pretty costly.

As a note, getting everything starting/running well is really more a matter of good, thorough tuning than the ECU.

seems very few have moved away from stock FI, and of those that did, many have gone to carbs, with the exception of mcmark and his turbo 4.

http://www.914world.com/bbs2/index.php?sho...54&hl=turbo

http://www.914world.com/bbs2/index.php?showtopic=97550

There was a guy a few years back that used GM ECU and other cheaply sourced parts and supplied it as a kit with loom,ecu,injectors,sensors ,etc to work with other stock components ,basically a programmable modern L-jet system,I liked the idea as it was reasonably priced and could be adapted to run with modified engines.
I think this system would be only good to a point as how far can you go with a single throttle body....don't really know.

I installed SDS way back in 2004, still running the same system in my bug but I re-chipped it to the latest version before V5.
Likely I'm one of the first here running a programmable FI system, at least on a DD.

http://www.sdsefi.com/

My 914 I ran it on a stock 1.8 and 2.0 with a mild carb cam with a pretty well stock D-jet intake (intake used on both the 1.8 and 2.0). Both engines ran flawless, perfect AFR, on the 2.0 I took the programmer off and ran it for 3 years (6+ month seasons) without ever checking it. I'd say it ran like a brand new L-jet, turn the key and go.

My bug is a super hi-performance 2.6L T4, 102x78mm, nickies, JE's, 2.0 big valve heads, Web cam, A1 1-3/4 exhaust etc, etc...
Only issue is because of the 46mm ITB's I can't get a good MAP signal and I have to run it as a TPS only system which may hurt my MPG slightly.
But then again it still runs flawless even on TPS.

I can tell you for 100% sure PEFI doesn't add a single HP, but it can run things, like a performance cam, that stock FI can never run.

I would guess that there are 5 to 10+ 914s that are running a variation of Megasquirt, I know Kieth Moon daily drives his.

PEFI alone adds no HP, but a proper tune on top of that PEFI will, especially if your system is controlling your timing as well. Having a full 3 dimensional tuning table for both fuel and spark allows you to dial in the tune and give the engine exactly what it needs everywhere.

So James.....just as an observer. What is the minimum required for that?

Hall sensor......knock sensor....O2 sensor?

I'm on SDS on the 2316 Raby kit engine that Drew Rickert built. Did a lot of mapping work on TPS only since the ITB's give a choppy MAP signal. I like the closed loop feature--makes the system seek 14.1:1 when cruising but will drop back to the tabled values when the TPS or RPM exceeds threshold values I set.
Something to note for those thinking about ITB's versus a single throttle body system is that for any cruising at 60mph or less the throttle is just barely cracked. These cars are so efficient, taking so little power to cruise. My readout for the throttle position sensor at idle is 4 on a scale of 50 at WOT. Any steady level road cruising below about 60mph the TPS is still sitting at 4 and will only move to 6 or occasionally 7 under mild acceleration. A single throttle body will provide more resolution to the throttle setting at the low power outputs in normal daily driving.
Then again, when I romp on it & go WOT it's wild acceleration with a sound from the intake that you can't wipe off with a fistful of $100 bills!

Marketing Koolaid

3D tuning table? does that help if you drive inverted?
Sequential helps with fuel economy, for the most part below 3000 rpm where the T4 and /6 aircooleds shouldn't be running anyways.
I'm running TPS only and my AFR is as solid as a rock through all RPM's

3D spark map A spark map is about as simple as simple gets. Once you have spark control the dark art of the dizzy curve goes bye-bye.

Proper sized and tune Webers still win at WOT.

Megasquirt MS3X full engine management (FI and ignition). 2056cc engine rebuild, moderate Web Cam (#86), 9.2 CR.

Yes, well he is gone now, died in a experimental plane crash. I have the manual for this, but you need to get the Eprom programmed. I moved away from the T4 world and never prosed it further.

I have several including SDS, MS, and one out of South Africa that is about as simple as it comes. A couple of old school home brew units. One of them has 5 dials on it, and you tune it like a carb, very interesting setup from the days of old when more people knew carbs than EFI. I have been into PEFI since the reenlist days, if that does not age me, what will

BTW, you can make a ton of power with a single TB, then new Dodge Demon uses a single throttle body. The Bugatti Chiron uses two throttle bodies to produce 1479 BPH so thats only 739.5 BPH per TB.

Chiron also uses quad turbos, and 16 cylinders but then you want to go fast you need to spend $$$$$$$$$$$

Who's going to tune your car? If you know that then go with an ECu that he or she knows well. If you're attempting it yourself then go with an MS version, that way you'll have the broadest experience base to fall back on. I did a Swedish built Maxxecu on my ITB'd 2276. It works well but I think it would have had the engine running faster and had more support from the MS community where there's alot of Aircooled experience.

^this....I had the very 1st running Megasquirt 914 I believe and Dave Hunt might have been the second. When I was calling around trying to find a dyno shop I was turned away from a few places that didn't want deal with it even when I was going to do my own tuning with the laptop.

Things have changes a lot since then and you will find shops that know it now. Local support is nice, I had a Link which I liked however only one West Coast person to talk to on the phone, not even sure if he still around that was 8+ years ago.

Not sure I understand the question here. The minimum you would need to have full program-ability of fuel and spark maps is an aftermarket EFI system that supports that. If you are talking minimum cost than Megasquirt is usually the answer and that can be built just about any way you want with whatever sensors you want as long as you have the know how to put it together (be warned is a pretty steep learning curve)

Must have:
Crank position sensor
Throttle position sensor
Coolant temp (warmup only) sensor
Intake Air Temperature Sensor
Wideband lambda sensor

With this you can run Alpha-N in wasted spark, will run fine.

Optional:
MAP-sensor
CHT-sensor(s)
Cam position sensor

Now you can run fully sequential and speed density and keep track of your CHT's.

Maybe if you are comparing to carbs but it does allow you to tune more accurately vs systems that follow an analog curve to approximate fuel requirements at given engine conditions see: Carbs, D-jet



Totally agree, sequential is a waste of time and adds needless complexity


Digital spark control is way more accurate/consistant than a dizzy at least all the type 4 dizzys i have played with. If you are only playing with an ignition curve in two dimensions (RPM + deg advance) you cannot optimize for all running conditions, 3 dimensions (RPM + engine load + advance) allows for this.



I attempted an autocross run entirely at WOT, turnes out other throttle positions are useful.

Nothing against carbs, they are just not my thing.

Alternatively:
Must have:
Crank position sensor
Throttle position sensor
Coolant temp (warmup only) sensor
Intake Air Temperature Sensor
Wideband lambda sensor
MAP Sensor

I have ran like this but you lose some features. Technically you could drop the coolant sensor too but then warmup in cold climates becomes a bit tricky.

But then you still had the distributor and no ECU control over spark/timing?
If you're going to do the EFI conversion today using the distributor seems like a half way there solution. Then you might aswell stick with stock injection or carbs.

microsquirt diagram

SDS. See my sig below for the install thread. It has been on 4 different engines, one turbo'd, and has been perfect. Easy to install and tune, rock solid, no failures. You have to want to do it and have an interest to make it all work. If you expect to open a box, mount a thing, plug in a wire, and live happily ever after, well, none of the systems discussed are for you. I quite enjoyed the puzzle and thought process of where to lay out the harness, how long to make stuff, where to mount this and that and the other thing. The tuning is, to me at least, pretty intuitive. I did mine when MS was just a baby and getting started. I wanted to go with a known system.

I have a friend with MS PnP on a 240hp turbo miata. He is an instructor for automotive technology. Smart guy when it comes to cars. His MS works great. But. Even with the wealth of knowledge of MS and miatas in that community, there were so many tables and settings, it took him a bit to find all the dark places in the software to get all the right boxes checked. It wasn't impossible, just took more time and patience that SDS required to be up and running. Then there was the laptop crash. And then the OS on his laptop was to old and didn't play well with the current MS OS he was trying to download and update to. So new laptop and OS. Then the his existing MS tuning files were in an older format that didn't just transfer to the new MS OS. Conversion headaches.

To my experience, MS is a fine option, just more goofing around to get it all right. The greater options in logging are nice. SDS was right, right out of the box. And with the V5 software and laptop logging options, even better. Nice that the laptop can log and assist you with the tune, but the operation of the system is laptop independent.

I sold Dave his SDS system.


SDS is hands down the simplest system to get up and running, often the factory program will run straight out of the box good enough to get you going. I've locked in the rough fuel maps in as little as 30 minutes of driving time, no dyno.

But there's many computer guys who don't like the thought of a pendant programmed system. The pendant is definitely different, but once you know how the scroll function works with the rich/lean knob, changing values is very fast.
V5 now addresses most of that with the 8 channel data logging, I believe with this you can now program with both the pendant and the laptop.

Many also believe you have to have sequential, in aircooleds running 3000rpm, the speed for proper cooling, the fuel economy of sequential goes out the window.

SDS is not for everyone, but it is a pro built, proven (23 years), good bang for the buck.

SDS has three versions
EM5 (EM 3-and 4) Fuel only
EM5-MSD (EM 3-and 4-MSD) Fuel with crankfire for MSD dizzy based systems
EM5-F (EM 3-and 4-F) Fuel and crankfire. GM based coils, one for 2 cylinders

BTW owners of older V3 and V4 SDS systems can upgrade to V5 for $580. SDS takes your old system ECU, gut it and install a V5 board and drill the case to install the laptop connector.

I have several running systems that I sold and/or installed
A 930 600hp monster EM4-F twin plug
A 930 hot street (guessing 350-400hp) EM5-F twin plug (now MS see note below)
A few vw vans EM4 mostly fuel only, stock dizzy
2 914 EM4 one fuel only one -F crankfire.
my SDS EM4-F system, in my 2.6L type 4 powered bug
and several systems sold, owner installed.

I have one customer who went from a SDS to a MS just this year, in hindsight he said he should have just stuck with the SDS as he's seen no performance improvement. But he does say the MS has more bells and whistles and he wanted to run COP, play with his computer, etc..
If anyone wants a lightly used SDS EM5-F /6 twin plug system PM me and I'll see if it's still for sale. It has the latest V4 chip.

A member asked me if he should ditch his homebuilt MS below was my thoughts.



As much as I like SDS if I do change to FI on my carbed /6 likely I'll do an MS this time around. We'll see... I've always had no problems with carbs and I love the sound of /6 webers at full song.

Now before I start this post, I am not in anyway an aftermarket EFI guru. I probably know just enough to get me into trouble. I come from an era of 55 chevys and air cooled VWs. When I have a EFI problem, I go to a guru.

That being said, another alternative for EFI you may want to look at is VEMS. A lot of the Audi guys are using this, and they are making some insane horsepower from 5 cyclinder motors.

My EFI guru is a guy named Mark Swanson at EFI Express. He replaced my 034 EFI with VEMS, basically because 034 is no longer supporting their product. VEMS is. Mark is a tuning and wiring guru. He makes his own harnesses.

While I was back there he was converting a 914 1.7 from CB to Megasquirt. One of problems he was having was timing. Now this customer did not want to spend a lot of money, pulling the motor and such to install a crank trigger was not in the budget. To get by this Mark was using the distributor, with a digital sensor. I don't know the brand. He was having trouble with the mechanical advance on the timing. Since the MQ does the timing for you, he eliminated the advance springs and welded the 2 plates together.

So if any one contemplating doing a conversion to MQ or more advanced EFI such as VEMS, and live in the Northeast, you may want to see this man.

One of the other cars he was working on while I was there, was a Ferrari Testarossa. He was installing twin hamster cages and VEMS.

Just for the hell of it, this is the dyno run on my other car, at his shop.

Greg W.

Coupe dyno run

That's one of the issues with many PEFI systems, there's almost no way to dial them in without expensive dyno time. Most of this is because the programs are so complex you have to be a pro with a dyno to dial them in.
That's the main reason I try to steer a novice and/or lower budget guy towards SDS, no dyno needed and 98% of the time you can get a good fuel map without a pro.
Once you have that under your belt you can look at a more sophisticated system.

These's are not a bolt on solution and they're not cheap, including MS.

Also I can say with absolute certainty there's way more PEFI systems sitting on the guy's benches then successfully installed in cars.

Thanks, ill continue to research the SDS set up and what all I need.

I still have the original manifold/throttle body. I'll start from there. I think I would want to upgrade everything else.

I have already upgraded all fuel lines to stainless steel but I know ill have to install a high pressure fuel pump since im currently running Weber 44's with a matched "carb cam"

Stock intake is the fastest way to get you up and running, then you can go from there. My first couple of set-ups were a stock 2.0 intake. Also you can use the stock 914 FI pump and regulator.

Stock 2.0 D-jet injectors work good, but you need to add a resistor pack because they are low impedance, (IIRC free on sds) you can remove this if you later decide to go with high impedance injectors.
1.8 l-jet and 1.7 injectors are not a good choice for PEFI.