Engine and Transmission Tech

tips, technology, tools and techniques related to vehicle driveline components

Go to Thread: PreviousNext
Go to: Forum ListMessage ListNew TopicLog In


RDMG
Dave R
Northern Virginia
(138 posts)

Registered:
04/07/2016 08:29PM

Main British Car:
1979 MGB 4.6L Rover V8

Fuel pump and regulator for returnless EFI on MGB
Posted by: RDMG
Date: June 09, 2017 11:20AM

Hi folks,

I just took the Bosch/Thor intake off my junker 4.6, and am impressed by the modern injectors and fuel rail on that setup.

The factory LR Discovery II fuel pump and regulator for the Thor system was a one piece, top-mount setup that dropped into the plastic fuel tank, with one fuel line going to the rail. No return line. Won't work in a B because the B tank has a side-access only.

Holley offers this, for $500 bucks:

[www.holley.com]

Not sure if it will fit through the B tank access hole.

Is there a factory (junkyard) in-tank or external pump and regulator option for a returnless EFI fuel setup on an MGB? I'm hoping something I could attach to the original sending unit plate/cap, or otherwise install without mods to the stock MGB tank?

The discussions I've seen so far here and on mgexp seem focused on the older return-type EFI setup.

I have a GEMS intake as well, and can repeat what's already been done with those, but the Thor fuel setup is so elegant, I'd really like to try it. The evap equipment in my stock B always gives me issues, and I'd love to remove it.

I have already decided a custom plenum is in my future, so that's not an issue with the Thor setup.

Curious to have your thoughts.

Dave



Edited 1 time(s). Last edit at 06/09/2017 11:59AM by RDMG.


Moderator
Curtis Jacobson
Portland Oregon
(4577 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: Fuel pump and regulator for returnless EFI on MGB
Posted by: Moderator
Date: June 10, 2017 02:45AM

I really like the Thor set-up too! I especially its nifty and uber robust stainless steel fuel rail. I came close to building my system around Thor parts.

But in the end, I felt like the earlier (14CUX) suited my particular situation better... I was determined to build my plenum with a removable throttle body facing directly into a firewall mounted panel-type air cleaner (i.e. true cowl induction). The Thor manifold's port layout provided a little less room for packaging my throttle body. Every quarter inch seemed like a mile. At the other end, I felt like the Thor thermostat scheme was just plain weird. Modifying a 14CUX (or GEMS) manifold to accept a Buick 215 thermostat housing required some welding and machining, but those modifications came together very quickly and cheaply for me. (Pics here.) I don't have any advice for you about returnless fuel supply plumbing except that IMHO, cutting a hole and putting an access plate on an MGB fuel tank is no big deal.

I think returnless is "cool", and it's certainly the road less traveled. More power to you!


RDMG
Dave R
Northern Virginia
(138 posts)

Registered:
04/07/2016 08:29PM

Main British Car:
1979 MGB 4.6L Rover V8

Re: Fuel pump and regulator for returnless EFI on MGB
Posted by: RDMG
Date: June 15, 2017 08:47PM

Your intake plenum is brilliant, btw!

I'm not as committed to the rear throttle body, but I can appreciate the value in it. Symmetrical, neat engine bay, high pressure air, etc. I imagine I'll run a hose through one of the radiator brackets for a cold air intake. I'm thinking I'll machine the Thor intake manifold to hold GEMS trumpets, and build a plenum around that.

It appears that the 2000s era ford escorts have a combined, in-tank, returnless fuel pump and regulator setup that is built around a gas tank acces plate (if that's what you call it) similar to the stock MGB setup. I can adapt a stock B sender assembly to hold it, I think, if it fits through the access hole. A 2.0L pump may not be up to the task, I'll have to research it. Somewhere on the internet I saw an EFI setup where a guy put a secondary tank in a battery well, using one pump to fill that, and another to feed the engine. I would definitely go to a CUX setup before I make things that complex.

I haven't thought about cooling systems at all. Thats next on the list, I suppose.

When I get a moment, I really need to start a project journal!


Moderator
Curtis Jacobson
Portland Oregon
(4577 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: Fuel pump and regulator for returnless EFI on MGB
Posted by: Moderator
Date: June 16, 2017 02:21AM

Quote:
Somewhere on the internet I saw an EFI setup where a guy put a secondary tank in a battery well, using one pump to fill that, and another to feed the engine.

You might be thinking of this inspirational article. (Scroll half way down.)

Quote:
When I get a moment, I really need to start a project journal!

Yes sir!


Sorry, only registered users may post in this forum.