So my 2.4 is fresh -0 miles with only start up minutes on it. I rebuilt the carbs and powdercoated the steel air filter assembly and replated all the hardware and am really thinking of selling the setup in favor of running a 3.2 fuel injection setup on likely with an aftermarket ecu as I don't think the dme will work well with my setup..

Any thoughts or experience with what I am proposing? Now note that I have done this on a 3.0 before with good success just no experience with a higher compression low displacement solex cam engine.. Thoughts?Click to view attachment

Contacted bitz racing about megasquirt options and also Sal cancelled about adapting the stock DME and that seems like an option as well.

My car has run pretty sassy on Webers for a long time.

DC-30 E/S cams.

I’d leave it as is - the ultimate coffee table.

@Larmo63 my only concern is that with the drastic temp changes here I will be messing with carbs all the time.. (Did that with my last -6).. I would think they would be awesome in a climate like yours.

Yeah, I see your point now that I looked at your location.

FI might be the ticket.....!

I would contact al lkosmal X-Faktory on the bird board. He has many documented efi conversions on small to large engines.

https://www.youtube.com/watch?v=e5_xXcJYXVc

sdsefi.com has about the simplest learning curve and works well with a single TB system. It also can be tuned as you drive saving on dyno time.
Can also be plugged into a a laptop with full data logging, fuel only, MSD or crankfire ignition etc.

Hmm that maybe worth a look. I just really want to run fuel as everything else is rebuilt as new

Em5-6D (includes harness)
options needed
1 bar MAP sensor
TPS
Bosch 12X1.5mm Temp Sensor

I'd also get a fuel pump relay

Mark what about cht?? And is there any base map or am I on my own?

I believe the temp sender I listed is for aircooled.

It will start right up with the base map. It tunes with a pendant that I mount on an old ashtray right in my heads up line of site.
It has a rich/lean knob, you do a steady rpm (say 3000) turn knob to the desired AFR on the meter (or pendant), look at the knob value, scroll to 3000rpm fuel value and enter the new value, done and onto 3250rpm. Rinse, wash, repeat.
Your map will be about 95% tuned after about a 45 minute county drive. At that time you do a data log to a laptop and look for things to improve on.

There will be many who say they don't like the system, too simple, most of the things they will cite are bells and whistles you don't need.
Below is the perceived bad points

-SDS is batch fired only, no sequential, but sequential is of little use on an aircooled because it's only effective below 3000rpm. This fact is right in the MS FAQ's. Sequential shines with fuel economy below 3000rpm, which is great for a water cooled engine, but lugging a aircooled engine below 3K isn't good.
-SDS fuel only systems doesn't have knock control, only available on the units with ignition control, but it's really of little use on a noisy aircooled engine.
-The SDS MAP sensor doesn't like a poor vacuum, for hot cams, big duration and ITB's you have to run "TPS only". MS is a hair better, but you would still have to run what MS calls "alphaN" which is a fancy name for "TPS only".
But this shouldn't be an issue at all with solex cams and the 3.2 single TB intake.
-Some can't get past the pendant tuning, too simple, too archaic, but to me it's a plus as you don't have information overload and can tune as you drive. All the missing info can be datalogged and reviewed on your laptop after you have safely pulled off the road. This can also be done in real time.

The plus
-Simplest EFI system to tune.
-No dyno tuning time needed.
-Easier learning curve for old farts
-real time or saved datalogging.
-harness included, custom injector harness.
-fuel only system can be installed and running in one weekend. Of course this is the electrical only on an existing FI engine, in your case doesn't count installing the 3.2 manifold, pressure reg, pump, plumbing, mods, etc.

On a T4 single TB 1.8 and several 2.0 I've done they ran exactly like a stock factory FI system, My car with a basically stock 2.0 and C25 scat cam I ran for 3-4 years never once having the pendant installed other than the initial tune.

Mark it looks like something that would be perfect for me.. Once I get all the 3.2 intake system in place I will need to check this out more in depth.. One question though does it come with injectors?? I didn't see that on their website..

Same sort of boat I'm in...trying to figure out either PMO 46 or engine management system. 3.0 liter, 9.5 CR, same cams as Mark.
Not sure what Ben was referring to with carb changes depending on temperature. I never had a problem... in cold, just press accelerator pedal a few more times to get it going. Then it'll run bailky for 5 minutes until warm. BTW, most of my experience is with small displacement Solex and S cam engines with Webers.

Do not have a system running yet but have been collecting stuff to do an EFI using MFI throttle bodies and stacks. They are available fairly cheap and the 2.4 heads have injector ports in them already. I think I will use the AEM system offered by Rasant Engineering.

It will have all modern engine management with a cool retro vibe. There are a number of these out there running in various configurations. Rothsport is beginning to do a few. If nterested I can send some links.

@Mark Henry - what would that sort of set up cost?

No system does, they do sell them separately, but you can find them cheaper.



This is where it gets harder to tune than Ben's app.
ITB's and large duration cams have a very poor vacuum signal that the MAP sensor needs to read. My T4, 2.6, hot cam, 46mm ITB's, I could never get a good enough vacuum signal to run on the MAP sensor so I have to run TPS only (alphaN). In very simple layman terms the MAP sensor acts like the a carb accelerator pump, poor vacuum could be loosely compared to a hole in the accelerator pump diaphragm. As soon as I gave up on the MAP and tried TPS only all my issues disappeared.

(BTW I just know someone going to argue that the MAP isn't an accelerator pump no matter my "very simple layman terms" statement. )



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

Ben's application, fuel only

Em5-6D (includes harness) $1115
options needed
1 bar MAP sensor $73
TPS $90
Bosch 12X1.5mm Temp Sensor $39

I'd also get a fuel pump relay $30
Optional fast idle, $100, I didn't get this 10-30 seconds of holding the throttle and then it idles.

other items needed
-Injectors (new style injectors will need fuel rails, not sure but the 3.2 rails might work)
-intake and TB(s), (stock will work may need sensor bungs welded in)
-FI pump (stock FI will work)
-Pressure regulator (stock D-jet will work)
-WB O2 meter or at least the sensor (SDS does read through ECU so gauge is optional)
-return fuel line.

Likely I'm missing a few items.

@tdskip they are about 1300-1600 depending on what you get . that's right from sdsefi.com

As to temp changes and carbs I can tell you that rejetting in our neck of the woods is very common as we have temp and humidity changes that swing from 100 degrees in summer to 35 degrees in fall and spring and don't talk about winter.. Efi compensates for this.

I don't know if that's the right head temp sensor, best to call.
My SDS head temp sensor screwed right into the stock 914 2.0 location. In fact IIRC it was the same as a stock 914 head sensor.

No I do not think so, once the carbs are set and you drive it at least once in a while they are good, especially with the electronic ignition that came standard with the 914-6. The weber problem is always from sitting, usually the idle jets collect some debris then foul a plug, and after some time sitting the floats stick and overflow. Other that that they will be good. We just got out the willow green 5400 mile six and the blue m471 six both had been sitting at least two years, and no problem with the carbs what so ever. (certainly other problems though!!!!)

Ben It seems I have the system your looking for sitting on the shelf, you want to talk a trade

Stephen yup let's talk again about this. I am interested @914forme

the main carb problem is Todays gasoline, if thats what you want to call it...

I'm on board with George's comment... and don't understand why fiddle with jets depending on outside temps. I drove the same cars in Florida heat, California mix, and all year long in New England (with many daily drivers). Same carbs / same jets / same settings... a few 912s, 2 67 Normals, 1 66 Normal, a 72 w/2.7, and a 70S.

So I'm heading down the path of PMO 46 for mine... am spending enough time on the rest of the car and would rather drive the thing!

Good point above about the crappy fuel we have to use.

I do have to agree.
Big swings in altitude, dirt, sitting long with unstabilized gas, bad gas and lower than average fuel consumption is what carbs struggle with.
To me the only big one would be bad mileage on a big commute DD, the rest of the issues are within my control.

If it was a DD and/or I lived in the mountains or planned to go through them, then for sure FI makes sense.

I would do FI but haven't because I don't drive my 914 enough, plus the fact my webers run incredibly smooth.

I think I am going to approach this as a 2 prong approach.. I will tune what I have meanwhile collect all the parts for the efi conversion.. Likely go with Stephen's sds that he has and Mark Epstein is sending me an intake. Then so will gather all the small bits.

I once built ITBs for a 3.2 out of 1999 to 2000 Suzuki GSX-R 750 throttle bodies. They are individual Keihin in those years. You can get 8 for about $300. I mounted them direct to the heads without manifolds. Throttle and fuel rail extensions were needed. Used MS3 but gave up after problems and went to Webers. Am thinking of trying it again as a "two pronged approach".

That's what I used on my 2.6 T4 into bug conversion.
http://www.914world.com/bbs2/index.php?showtopic=210004

Here's a few pics of my attempt back in 2013.

The trumpets were actually for a Yamaha R1 with Mikunis, but I cut them down in a lathe to fit the Keihins.

Triple Speed Triumphs are the hot ticket @MB911 we will be in touch, I have almost everything you will need except the air cleaners, I was going to take a metal 911 unit and make it work on the adapter plates for the Air filters.

I have a set of PMOs for my -6 and well that is about as good as it will gets running carbs.

I have used a 3.2 Intake on several engines with programmable ECU's. They all worked very well but I used pretty mild cams. Most aggressive was a 2.7 with E cams and it worked well (actually originally used CIS but had to set idle a 1300RPM to get it to idle). Since the overlap on solex is similar to E I think you will be good with 3.2 intake. When you get into cams with more overlap then reversion on a common plenum manifold can be a problem. Sequential injection can help as you can trigger injector after exhaust is closed at low RPM. Batch does not work well with large overlap and common plenum. ITB with big cams works well because throttle plates limit how far the A/F mixture can get pushed up the intake.

john

PMO makes throttle bodies to replace the Webers., so you don't have to do any changes to linkage or mounts.

And the latest version of the Megasquirt software comes with a hybrid mode. Meaning it runs in Alpha-N at idle and transitions to Speed Density as the engine spools up. You can run high overlap cams and still have a decent idle and good throttle response down low.

Some parts came in this week for this.. Still planning to do this but maybe long term.. I do also think about using my Webers as throttle bodies.. That is also an option.

+1 for SDS. Mark speaks the truth. i got my system from him and have used it with ITB's for several different engine and cam combos. One of them turbo'd. Click the links in my sig for details of my SDS adventures.

I agree that is SOME applications it is limited- wild cams and ITB's are tough, but do-able. Other systems might deal with this more gracefully. But again, my experience has been patience and persistence will get the tune right. Just use the tools at hand to give the engine what it wants. Pretty simple.

All that stuff is cool but if your cam isn't lumpy CIS is a very good and reliable system.

but I'm pretty sure Ben is going for a certain "look" as well as a performance oriented solution.