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

[Superhawk996]

What is with with the love of TBI?

Sure dual TBI on custom manifolds would be better than running a singular TBI through stock 914 manifolds.

But what have you gained?

Now you have a linkage that needs to be synchronized. Just like dual carbs. Just like dual ITB’s running multi port injection.

Now maybe need two TBI ECUs to manage two TBI’s? Now you have all the disadvantages of what has basically become an ITB setup with its issues of low and unstable vacuum signal to run a MAP sensor off of.

Dual TBI would need custom intake manifolds. At least current T4 ITB - multiport setup uses commercially available manifolds from Weber / Dellorto setup.

TBI is not some sort of magical fuel injection system that is inherently easier to tune than a multi port setup.

Am I missing something? I promise I don’t hate TBI but it is inferior to multi port injection. TBI was an emissions band-aid for a short window of time in automotive history. I’m not seeing how it makes life any easier when installed on a 914.

[Jack Standz]

What is with with the love of TBI?

Sure dual TBI on custom manifolds would be better than running a singular TBI through stock 914 manifolds.

But what have you gained?

Now you have a linkage that needs to be synchronized. Just like dual carbs. Just like dual ITB’s running multi port injection.

Now maybe need two TBI ECUs to manage two TBI’s? Now you have all the disadvantages of what has basically become an ITB setup with its issues of low and unstable vacuum signal to run a MAP sensor off of.

Dual TBI would need custom intake manifolds. At least current T4 ITB - multiport setup uses commercially available manifolds from Weber / Dellorto setup.

TBI is not some sort of magical fuel injection system that is inherently easier to tune than a multi port setup.

Am I missing something? I promise I don’t hate TBI but it is inferior to multi port injection. TBI was an emissions band-aid for a short window of time in automotive history. I’m not seeing how it makes life any easier when installed on a 914.

"Now you have a linkage that needs to be synchronized. Just like dual carbs. Just like dual ITB’s running multi port injection."

Why can't you run a drive by wire system? You know, to address the synchronization pblm?

"Dual TBI would need custom intake manifolds. At least current T4 ITB - multiport setup uses commercially available manifolds from Weber / Dellorto setup."

So? Doesn`t seem so difficult a fabrication problem for any vendor that I'd be willing to purchase Type IV manifolds from. As you point out, IDF manifolds require customization for MPFI anyway.

"TBI is not some sort of magical fuel injection system that is inherently easier to tune than a multi port setup."

Honestly, was hoping the self-learning modes of some of these systems could be incorporated to make installing and running such a system inherently easier. Of course a magical system might be even better (IMG:style_emoticons/default/smile.gif).

"I promise I don’t hate TBI but it is inferior to multi port injection."

I don't hate FI either. But, the point is maybe a slightly "inferior" system that is more reasonable in cost and less time consuming to install/run has a certain appeal to us non-enginneers and non-electronic gurus.

Best wishes for your next fuel delivery system and induction methodology.