Lotus Elan and Lotus Elan Plus 2 Forums

Hi there,

I was wondering if any of you have fitted a fuel pressure regulator in combination with an electric fuel pump.
I have a "Fuel King" regulator that I want to fit & am looking for a suitable place in my S4 to fit it.
The fitting instructions say that it has to be fitted in a horizontal position.
Do you know if this is absolutely necessary?
It would take up less space when mounted perpendicular, would its function be affected?

John

My S4 runs with a Facet Red Top fuel pump via a Filter King to the carbs. Most electric fuel pumps provide too much pressure for the carbs and need to be limited with some sort of regulator.

I mounted the one on my S4 as per the instructions. I agree finding some space for it is a bit of a problem. As my S4 does not have the original air box I mounted the Filter King on the inner wing next to the carbs. I can send you a picture if required.

Thanks Steve,

My Zetec engine has 45 DCOE's & a larger TTR airbox so the space there is very limited.
The Facet pump & remote fuel filter take up most of the space that is available to the right of the fuel tank.
Thanks for the offer of a picture but as you see it will be of little help in my case.
I will have another look around the engine bay on the weekend & maybe find a place underneath the Webers or even squeeze it in next to the pump.
It'd be a lot easier if I could turn the thing on it's side though

Did you need to adjust your regulator or did it work OK straight from the box, as the instructions with mine seem to imply?

All I'll be doing is looking at the moment; it's too bloody hot here to be contemplating playing with spanners

Cheers
John

I put my electric pump and filter in the RH side boot cavity. I made a simple wooden platform that made a nice horizontal surface to screw the pump down. I ran the supply hose around the rear of he petrol tank and the feed hose around the front of the tank. Very simple.

Don't forget you need a safety inertia cut-out switch somewhere in the electric circuit.

Hi,

Sounds like we have similar set-ups regarding the pump & filter except that I bolted mine via the rubber vibration reduction mounts to the rear of the wheel arch down in that area.
I also cut a plastic washing up bowl down to size to fit inside the spare wheel so that the displaced tools, except the Jack, have a new place to live.
I must have another look to see if the pressure regulator will also fit in alongside the pump & filter
The pump is wired via the engine management system which has an inertia cut out.

Thanks for your advice
John

The Filter King came already adjusted to the right pressure, no need to mess with it. If you do want to adjust it you will need a fuel pressure meter. IIRC 2-3psi is what the carbs want.

John,

As a matter of interest, what engine management system are you using?

I placed my electric fuel pump in the boot on rubber, vibration isolators. I fitted an inexpensive, in-line pressure regulator to the end of the OEM fuel line in under the carbs, where it is horizontal and set to about 2-psi. I believe Webers want fuel at 1.5-3 psi at the inlet.

I currently use the OEM, 40DCOE-18 Webers.

Bill

Thanks everybody for your comments & tips.
It seems that nobody on here has attempted to fit the "Fuel King" tipped on its side.
I imagine there would be a problem with the "Filter King" which is the same piece of kit but with a filter bowl slung underneath it.

Brian,
all the special bits for my Zetec came from Dunnell Engineering including his own engine management system.
This would also work with the Twin Cam provide it is fitted with a "Phonic? wheel".
Paul's 3D system takes signals from the crankshaft, water temp. & throttle position.
Would be nice paired together with "Pencil Coils".
The Zetec coils use lost spark.
I made an error in my description.
The management system shuts down the fuel pump should the engine stop turning.
I'm sure he won't mind me telling you this; Paul learned his trade from his Uncle who was the man behind the name "Holbay", so the man has a good "Pedigree"

Mine is fitted as shown but without the standard airbox etc. Has been fault free so far.

Ah, yes I think that's the way to go.
Bags of room there because my radiator's right up front
Ta!
John

Do most cars have a regulator fitted? i dont believe mine has..what are the benefits?

Talking Elans only;
no, the carbs are normally fed by the engine driven mechanical fuel pump.
Those that switch over to an electric pump mostly fit a pressure regulator because those pumps usually deliver the fuel at a pressure higher than that for which the carbs are designed to run at.
Perhaps somebody else will be able to explain more eloquently.

Cheers
John

Thanks John..im not sure if i have mech pump or electic,is there a way of telling or do i just go look at system?

rocket wrote:Thanks John..im not sure if i have mech pump or electic,is there a way of telling or do i just go look at system?

Peek down the side of the block between the carburettors. See if you have a device with a glass bowl on top bolted to the block at about mid-length. Then see if there is a hose running from this device up to the carburettors. If so you have an original mechanical fuel pump. If you have a device there with something other than a glass bowl it is likely a replacement mechanical pump. If you have neither then you may have an electric pump. An electric pump could be anywhere as this is an owner modification. Elans and +2s all had mechanical pumps when they left Lotus. Recent replacement mechanical pumps have the same problem as most electric pumps, i.e. too high a discharge pressure. This can cause the pump to overpower the needle valve/float system and overfill the float chambers. The original mechanical pumps discharge at roughly 2 psi.