2.4s -6 engine fuel injection options Options

[mb911]

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?

[dr914@autoatlanta.com]

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!!!!)

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

DC-30 E/S cams.

@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.

[914forme]

Ben (IMG:style_emoticons/default/bye1.gif) It seems I have the system your looking for sitting on the shelf, you want to talk a trade (IMG:style_emoticons/default/shades.gif)

[mb911]

Ben (IMG:style_emoticons/default/bye1.gif) It seems I have the system your looking for sitting on the shelf, you want to talk a trade (IMG:style_emoticons/default/shades.gif)

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

[sixnotfour]

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

[roblav1]

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.

[Mark Henry]

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.

[mb911]

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.

[roblav1]

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".

[Mark Henry]

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

[roblav1]

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.

[914forme]

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.

[targa72e]

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

[ClayPerrine]

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.

[mb911]

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.

[ottox914]

+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.

[rick 918-S]

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

[mepstein]

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

(IMG:style_emoticons/default/agree.gif) but I'm pretty sure Ben is going for a certain "look" as well as a performance oriented solution.