Hey i was just wondering if anyone has run the ebl with a multiport set up?? I would like to turn my tbi into mpfi. I was thinking a holley mpfi manifold and injectors with some wiring mods etc. Any comments or knowledge on doing something like this. I'm going to be ordering the ebl soon and would like to uprgade to the multiple injector option. But i dont know about running this style of set up. Any help would be great. Its going to be the 7747 ebl and yes i have the prom tuning eguipment. Thanks for your help.

 

The intake might be a good idea, but the injectors supplied with that kit were junk. I think they were called pico's?? Anyway they had some funky impedence to work with the stock TBI injector drivers.

Rbob should be able to get you the parts you need to convert your ECM over to handle 8 low inpedence injectors, I'm not sure what is required to run high impedence injectors. You might look at using any FI type intake designed for a carb intake with an adapter for the TBI unit if you still want to use it. A lot of guys have had luck using big mono blade TB's off of other GM vehicles.

 

Yes i would be willing to use different injectors, just not sure what to get?? I was just thinking of the holley manifold, because it already has the injector bungs cast into them. I would probably use my current tbi adapter and gut the tbi unit for the air-valve etc. Im looking to see if anyone has done this or has the knowledge to do so??? Rbob if you read this i would really appreciate your wisdom!!! Its kinda like the edelbrock idea, but i dont like there design and dont want to spend that kind of cash for something that i dont like. Any help is appreciated

 

Personally, I've been running one of the Edelbrock MPFI manifolds with 35# Magneti Marelli pico injectors for about two years with no problems. However, I don't use the 7747, but use true batch fire mode with a 7749 ecu. Also, the impedence is typical of a high impedence injector, nothing really odd about them.

I think that issues could arise when using the Edelbrock MPFI conversion with a 7747 in non-stock (higher HP) situations. You'd need very low idle pulse widths that might be lower than required for consistent injector operation. Also, at higher RPMs, you might run out of time between DRPs for the required pulse widths.

...just my .02

 

With a stock saturated injector I would recommend that the RPM be kept down, 4800-5000 max. If going with PnH injectors (and a modified ECM) the RPM range can be extended another 1000 RPM. This all has to do with the TBI ECM firing the injectors twice as often as a port ECM setup.

The pico injector is a 'low mass' design. This allows (allegedly) to open and close faster then a typical saturated injector.

RBob.

 

I just got my hands on a 19 lb. Pico injector from an Edelbrock MPFI conversion. I am going to test it to see what the actual open/close times are compared to a 19 lb. SVO I have lying around. My guess is that the times are much closer to typical saturated injector than they are to a Peak & Hold TBI injector.