I'd picked up a '63 Rochester manifold and doghouse with the idea of converting it to EFI. For the purests, it was without dist.,fuel meter, air meter, or ID tag, and had been crudely polished so it had little value for restoration. I made an adapter for a throttle body, and fiddled around a bit with a CFI Vortec spider making bits to hold the pintles in place, but never really got excited about it. Now I'd like to revisit the project from perhaps a different angle.

With the release of the new Stewart fuel pump, we have the ability to have fuel pressure in excess of 3bar throughout the RPM range, and a pump that doesn't need fuel flow for cooling or to prevent cavitation, and because of the constuction will have minimal heating of the fuel.

It appears, in my little pea brain, this could allow a returnless system. Comments?

I'd played with the CFI unit because it could minimize visible wiring. However, mounting of unit, and extending the lines will create some issues other than just capacity.

So, I'm open to what some of you might do to try to make it simple, but retain some original "styling" clues. Things like individual fuel lines with "hats" rather than a rail and means of hiding the wires to individual port injectors, low profile injectors, things that might fool the eye for an instant.

I doubt you can run it returnless. The OEM "returnless" systems either still have a regulator in the tank, or the Fords pulsewidth modulate the pump and have a rail mounted fuel pressure sensor.

You might be able to do it, but the differential pressure would be all over the place based on RPM and load I would assume and your tuneup would be a mess.

Although not ideal, you could run a return regulator (hidden) before the rails and dead head the rails which would give you consistent pressure (like the Dodge and some GM systems with the regulator in the back of the vehicle). The downfall is heat soak problems/vaporlock problems.

Are you trying to make it look the original mech setup and hide the EFI?

Doug,

There is little chance of making it look enough like the original mechanical unit to fool very many "car" people, and the others wouldn'd know or care about what they were looking at. Fuel "rails" are out because the throttle body is too low, unless there are shorter injectors than I'm familiar with. I've never had one of the units Edelbrock uses so I'm really in the dark about their height.
My main issue is underhood "clutter". The fuel pump idea, they claim you can maintain a constant pressure to 50lbs, was to eliminate another fuel line and to reduce the possibility of the fuel pump whine often associated with EFI. It would seem that the regulator would be the main issue. I can't see heat soak issues being much different than carbs, unless it just flat couldn'd purge, whereas a carb vents. ????

I know that pump, but don't know much about it. Unless it is internally regulated, which it might be, then I can't see it maintaining 50 PSI at the same RPM under different load conditions, in other words, cruising at 3000 RPM has a low fuel demand and at 3000 RPM at WOT, the demand may be 5x which will lower the pressure.

If it would world, that would make things significantly easier for EFI retrofits.

I think I'll take a bigger look into the pump. Let me know what you find.

Yea, I don't think you'd have any significant isssues with heat soak unless it was an extreme heat situation. I ran a car like that for a while with no problems.


The shorty injectors are pretty short. I don't have a mech efi system in front of me :), but you could make two short fuel rails on the one side so they don't interfere with the throttle body possibly. Or use the MSD available parts and hardline the feeds on the injectors and thread the injectors into the bungs. If you want more info on that ask please or see an MSD catalog.

Doug

Here's a link to the pump showing construction detail, and to the left, the "features" page will have more info. http://www.racepumps.com/tech.html
The claim, "constant pressure" because a spring is what pushes the fuel, and the claim also is it'll work with EFI. The proper regulator will need to be found.
I've really no knowledge of who makes options to the fuel rail, however I'm much more interested in something that is "hardline" rather than fuel rail. Although I love doing little projects like this, I may be forced to send it out to someone who does conversions for a living.

Looks like a regulator would be needed.

The little I read from you, I'd say you'd be more than qualified to do the work yourself. To much shoddy work out there if you send it out.

BDS (Blower Drive Service) also has a lot of EFI hardline stuff. They use it on the 8/16 injector Roots EFI plates.

Here is the MSD stuff:
http://www.msdignition.com/fuel_9.htm

Here is some BDS stuff, no pictures that I saw though:
http://www.blowerdriveservice.com/categorynarrow.php?partnumber=3471&page=60&limit=10&compid=101011&YMM=&reorder=&sort=&dealer=&engine_id=&&brand_id=&year_model_id=&price_id=&category_id=&distributor_id=&model_id2=0

Some of their stuff ain't cheap though!

Doug