Decision time soon (preferably only once). Later this month I will pick up my refurbished case, crank, and heads from Competition Engineering in Phoenix. I want to build this up to 2056 and use fuel injection.

So, do I keep the stock D-jet that was on the car? I have no idea if it works. And I expect that I will spend time and money tracking down rebuilt/replacement components. Plus modify the system for the increased displacement.

Or do I go aftermarket, spend more time and money, but hope for better results? And maybe some sexy twin intakes?

My son is running stock FI on his 2056 reliably now, so you can reinvent the wheel, but for such little return why (if you have it already)?

Sorting through the D-Jet would be my first priority. Take stock of what is good and what needs replacement. Then you can make the choice.

What parts and pieces do you have? A complete 2.0L setup with what ECU? MPS?

Going aftermarket really opens up your choices as far as cam selection and head work which will make a huge difference in how your engine performs. Aftermarket will also allow much more accurate fuel and timing control which will also affect how your car performs. Add to that the fact that all d-jet is 50+ years old now and pretty much all new parts are NLA, including some parts that are absolutely necessary for the system to run and the fact that even when new d-jet had its shortcomings/limitations.

Dont get me wrong, d-jet is a fine system for what it is. 3 of the 4 914s I currently own are d-jet cars at the moment but my car with a built 2056 and Megasquirt is just a night and day different experience from a driving perspective, especially when you have built a motor to take advantage of it.

I think it really should depend on what you are looking for. If you are going for concourse/originality or don't want to spend the time and money to go aftermarket, stick with the d-jet setup you have but those are the only reasons i would consider sticking with d-jet at this point (and sticking with d-jet may wind up being a false economy in the long run anyways)

Im currently recovering a numbers matching 74 LE bumblebee, its getting the last of my stash of 2.0 d-jet parts but its been a fight getting it running correctly and I spend the whole time wishing I could just let myself put Megasquirt on it (but i wont due to originality purposes) The rest of my d-jet cars will eventually be getting Megasquirt, just not at the moment as they are currently running fine.

If implemented correctly(and this is key), better results are a guarantee.

Twin intakes are an unnecessary cost and added complexity if you already have the D-jet intake, but they do look awesome so do whatever suits you!

Also once you have gone aftermarket injection its usually pretty easy to swap induction later down the road so dont feel like that decision needs to be made day 1.

A "second" on James. I'm running Microsquirt with the stock D-Jet induction bits (incl t-body), dead stock engine. I get no change in MAP (95.x kPA) on WFO throughout the rev range up through 5500 RPM.

I'm building a 2056 with bigger valves and cam over the winter, so it'll be fun to see if the D-Jet induction can handle the additional airflow.

Plus, dual t-bodies are louder...

I’m planning aftermarket FI my 2056. And I thought I wanted ITBs, but I don’t want to have to sync anything. That's one of my reasons to convert from carbs to FI.

So here’s a question... Is there any reason to think the stock djet runners, plenum, throttle body won’t flow enough air for a 2056?

Discuss - I’m riding down the highway through Planet Utah.

Click to view attachment

You coming this way?

I think you would need a pretty extreme 2056 before it becomes an issue to consider. I dont recall the exact figures but i did the math on it before and I think it doesn't become an issue until you start getting above ~140HP at which point you also need to be thinking about exhaust (headers) as well.

Mine is a bit of a screamer (spins to 7k) and im running it through a modified 1.8 l-jet Plenum with 50mm Vanagon TB. I suspect where you are at the stock 2.0 plenum and runners would be preferred from a drivability standpoint as it gives a better vacuum signal, and in theory probably better midrange torque.

Mine revs to 6500 rpms without any problems

Ditto.

Wait a few months and I can tell ya...but it's CT so I can't see this thing hitting a dyno or track until April, soonest.

GA

Thanks, everyone. Right now the plan includes stock-ish heads and valves. No cam selected yet. Or exhaust.

One concern I have about starting with the stock system is sinking serious money into that and then deciding to go after-market. For example, my D-jet wiring harness looks bad. A new one from Jeff B will cost more than $500. And since I have no idea if the system even works, I have to guess that one or more major components will push the budget over $1000. And right now I would rather spend that (and probably more) on newer technology.

Exactly why I decided to go Microsquirt. And I'm a big proponent of the D-Jet system (it's really pretty good).

James is sharp on this stuff, and here's my decision matrix from last winter that led me there:

https://tgadrivel.blogspot.com/2020/03/on-m...914-part-1.html

The Dub Shop offers a bolt-on dual-throttle-body system system if you're not a DIY'er.

Thanks Greg and James for the input. I appreciate it.

@GregAmy - Your site is on my to do reading list.

@JamesM - I didn't realize you were that close. I stopped and PMB yesterday we and had dinner with Eric, Dianne and Nicole. We're already in Vegas doing a whirlwind parts drop/pickup tour on our way to the beach. I keep thinking about all of the things we could have done *if* we'd had more time.

@bkrantz - Here's another approach. You can use a lot of the D-Jet parts in an aftermarket FI set up. Many have done it this way. You don't have to do a wholesale change out. You use parts that work and fit the application like the runners, plenum, throttle body but get rid of the problematic/NLA/priceless pieces like the injectors, MPS, TPS, brain, etc...

There's a difference between getting the DJet system functioning and restoring the system. There's no point into going the level you have on your car and not fully restore/sort the system which won't be cheap.

On my car I started with a somewhat functioning DJet system and have spent over $1500 into parts alone to bring it up to my standard. Harness, injectors, MPS, etc. The good news it is now a reliable system that I can trust however it didn't come cheap.

Unless you're a dedicated fan of DJet then I would suggest aftermarket FI.

With Djet intake and SSI's there's no way in hell you can get 140hp, at least not without fudging the dyno numbers, even 130 would be a stretch. That said the stock d-jet intake and SSI's will work fine for a 2056.

Spins to 7K? Is this a full race engine? What are you doing about valve float? What cam?

I'm in the process of sorting out the D jet system on my 73 2.0 presently. There is mention in a previous response of "A new one from Jeff B will cost more than $500" with reference to a replacement fuel injection harness. How does one contact Jeff B?

Thanks,
Mark

You don't want to leap into Djet with a NEW 2056 long block and install a bunch of possibly mismatched or questionable old FI parts. You're going to burn thru that $1k budget in short order. Lots of little things as well and they add up quickly. The 'while you're in there's. You can't be chasing gremlins trying to start and break-in the engine. Have you bought your cam and lifters yet?

Member JeffBowlsby

https://bowlsby.net/914/WiringHarnesses/

Mark Henry,
Thank you for the reply with link.

Mark

Thats what i am saying, you will run out of exhaust before you run out of intake with the stock plumbing.

As for my motor, its used in my dedicated autocross car but I have no idea exactly what is in it as I bought it as a fresh long block from Bruce Stone. It was a motor his son had European Motor Werks build but he changed directions on his project before ever installing it. I was looking to build a new motor for my autocross car at the time it came up for sale at a price to good to pass on. Im pretty sure the cam is one of EMWs but no idea which one. Things i do know about it from external observation, It has reworked AMC heads, some pretty massive stainless valves, dual valve springs, solid rocker spacers, 911 adjusters, and the flywheel was seriously lightened. They told me EMW had also done some custom combustion chamber work but that I cant confirm as I have never pulled the heads. It comes on cam noticeably around 3800rpm, and pings pretty bad with anything less than 91 octane even at my 4500ft elevation. and yes its running the 4-1 Eurorace headers

Was told it has AA pistons in it so yea... i don't normally run it up to 7k out of an abundance of caution, but it does get there without much fuss. When i was initially tuning the fuel map I pretty much just let the motor run to where it wanted to run to and found power didn't start dropping until after ~6500 rpm, I was a little shocked when i checked the logs after and found I was hitting 7k+. since tuning it I usually run it with a limiter set at 6500 (depending on the course) that I am pretty frequently bouncing off of when autocrossing. Not sure how i didn't blow those AA pistons (if thats what they actually are) to pieces, perhaps they are better than people tend to imply?

Honestly this motor feels more aggressive to me over 5k than my buddies Rabby cam'd 2270 with ITBs that i tuned MS on. Havent had it on a dyno yet but one of the local shops that does air cooled cars recently got one, so I hope to get over there come spring to see what she has left in her after 4 seasons of abuse. I can say that with my setup I am seeing slight increasing manifold vacuum at the top end while WOT so I suspect I am starting to run up on the limit of what the intake can handle.

Ill have to see if I still have the datalogs on those 7k pulls, they were a beautiful thing.

Not yet. Waiting to make some intelligent(???) decisions about the complete motor.

I don't know what a complete aftermarket fuel injection system would cost, but I'm well over $1500 piecing together my 2.0 D-Jet FI system. I put a WTB add up for a complete system and paid going rate a few years ago plus new fuel injectors because when I flow tested them they were clogged and couldn't be repaired. Also bought a reman 2056 MPS from Mr Bowlsby along with some other odds and ends. It's all together now and seems to run nicely after chasing down vacuum leaks which turned to be a replacement 2.0 throttle body (more $) and now that all is said and done, I would have, could have and should have put big valve 2.0 cylinder heads from Len Hoffman. In short, think the whole thing thru first and stick with the plan and you'll have a good result. Good Luck.