Aftermarket FI options for Type 4 motors 2056 or larger, Who here has gone this route and is it worth it? What options do we have? Options

[DRPHIL914]

i started looking into this 2 years ago when i was planning my rebuild motor after the drpped valve seat on the OEM motor.
I ended up building a nice 2056 with increased compression, brand new heads, counter balanced crank and of course the cam is performance minded as well.
to start i installed the d-jet and later last year i added a 50mm bored out stock throttle body from Tangerine/Chris Foley. Yes this helped a great deal, but we are still limited due to the d-jet and the MPS. So there are a few people out there that make ITB( independant throttle body) that could be used.
One is Jenvey, and i see that PMB is carrying those. It looks ike they are mated to what ever IDF intake manifold you choose. there are 40, 45, 48 options. mated with 350cc injectors.
I am wondering other than the CB performance stuff that has been available for a while, others have come to the table, who here has played around with this ? over the years ive read a lot on others using the megasquirt and micro etc and it seemd they were very difficult to tune and set up with lots of problems, trial and error.

I am looking for advice on what to stay away from and what are the pitfalls and mistakes we can avoid before jumping into this.

Look forward to some input, thanks!!

Phil

[emerygt350]

I work with early tbi (CFI in the ford world). It really is better than carbs by a long shot. Poor fuel distribution is a manifold issue (just like carbs). Mpi is better of course but I wouldn't go bragging up our bank fire system. Runner length is still up in the air for me. Velocities are so high and engine heat eventually gets there as well. Obviously mpi would be better but I just don't by it as a show stopper. Modern mpi engines can have incredibly long runners.

[Superhawk996]

I work with early tbi (CFI in the ford world). It really is better than carbs by a long shot.

By what metric?

Emissions - Agreed. TBI was a response to inability to meet emissions regulations.

Lack of jets and small air passages to clog - sure. But now you add other sensors and actuators to system with their own associated failure modes.

Performance - no so much.

Long runners on modern engines are a function of them only having air flow in them and the fuel delivered at the intake port. Long runners of a 914 that are largely isolated from the engine will take much longer to warm up than an aluminum manifold bolted directly to heads nestled down in the valley of a V8. Not to mention the nasty, nearly 180 degree turn the air fuel mix has to make to enter the intake port of a 914. That turn is a recipe for fuel to fall out of suspension as it slams into the wall of the runner. Fuel has mass and it wants to travel in straight line rather than execute a 180 degree turn. Physics and all that.

Virtually all the performance gains of the last 30 years came from the benefits associated with port injection and direct ignition. Precision control over fuel and spark. TBI and an antique distributor isn’t optimal.

In my opinion, there is no point in taking the trip to get rid of D-jet / L-jet or even a set of well tuned carbs to land at TBI on a 914 T4 engine. Too much hassle for too little gain.