Lotus Elan

fuel injection

PostPost by: seaandmoor » Fri Jan 22, 2010 9:46 pm

I've been idly thinking about this on my Plus 2 because I've had Megasquirt ECU, wasted spark EFI with trigger wheel, coil packs and EDIS module on a V8 for about three years now and it's absolutely brilliant plus you can plug into a laptop (older type with correct port) and adjust the fuelling/timing/air fuel ratio and lots of other stuff. However, it was obviously easier in my case because I already had fuel injection and only needed an addition to the loom and some brackets.
TB's are the most expensive part and will probably leave it until there is another reason to take the car off the road.
Good luck though and do post some pics to show it all going together and a note of pitfalls to be avoided to spare the rest of us the 'agro'
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PostPost by: RichC » Thu Jan 31, 2019 5:43 pm

[/quote]Don't use plastic fuel pipe. At the pressure and flow rates you will generate in a fuel injection system you run a risk of static burn through. The OEMs know what they are doing when they use plastic, we should stick to conductive and hopefully corrosion resistant metallic fuel lines.



I'm just looking into EFI petrol lines ( but for my twink but sunbeam alpine with a holbay engine )
and have found this old thread . I was just about to plump for some nylon fuel line from my local diesel fuel experts and this has given me second thoughts ... I had thought of aluminium fuel line but the route is too tortuous and i'll need some flexion to the fuel rail . Another thought was teflon lined rubber with nylon or stainless braiding , but the local store reckoned nothing wrong with nylon up to 3 bar ...
I'd be interested in the general consensus as i've never heard of static burn thru ..... :wink:
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PostPost by: rcfurse » Thu Jan 31, 2019 6:19 pm

I put hidden EFI on my DB car. I suggest you ask someone who does these conversions all the time. If you are in the UK, ring Adrian on 01244 537701. I have no ? connection other than using him to do EFI and Carb work for me (He does both).
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PostPost by: TomR » Fri Feb 01, 2019 1:44 pm

Never experienced static arcing/pinholing on lines I've used but it sounds like a real thing if you have high flow velocity in a long fuel line where the fuel and fuel line are very nonconductive. Maybe someone else has actually experienced this?

In any case in my Elan the Motec EFI system runs well above 3 bar. You might want to verify the expected operating pressure of your system (depends on your injector choice, mine are a bit small but responsive) and check it against the max operating pressure of your line at the max and min temperatures that any part of the line will experience.

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PostPost by: pauljones » Sat Feb 02, 2019 11:19 am


Doesn't time fly, i started this thread 9yrs ago. So as an update ill add a few things,altho there is another topic with the info and the dyno printouts.

The main parts i used are the Axminster EFI tank with internal swirl pot and the return which feeds into it.
I run a filter, then 044 pump, then a second filter and via the pipe work, yet another finer filter prior to the fuel rail.
The injectors also have a micro fine filter built in,most do too.
A fuel pressure regulator smooths out the pulses and returns the rest back to tank return.
Ecu is Emerald and was RR'd at JKM in Portsmouth, but Slark Racing later fitted a wideband 02 and put her (Sophie) back on the rollers and tweaked her for a bit more torque and set the map to run a leaner mix.
The pipe work is all labled as fuel pipe and uses jic fittings where possible.

So anything id change, the basic elements are all there and altho i went with emeralds ecu, you can get cheaper but not by much i think. Its really what your prefered rolling road operator is happy with.

I used jenvey bodies of 40mm, these flow more than i need so perhaps a swap to something smaller would increase port velocity and give better response to the load peddle inputs.
Since fitting mine i have done simmilar swaps onto zetecs and 4age units and have had great results using bike bodies but these may need slight mods to fit. The cost of these is very eye opening.

Other things as extras i had to buy were ignition leads (halfords trade card)
Bosch gen 2 ignition coil pack, same source.
Trigger wheel front pully combo (qed)
Blanking plates for fuel pump and dizzy. Not sure source.

Things i forgot about,
I had some old but new k&n filters but were very thin. These stopped the fitting of inlet trumpets. Also as some have suggested suck in hot air instead of cool denser air from the front. I have since upgraded mine to a very reasonably priced ramair setup which allows fitting of ram pipes. If i had the time and patience id make a fibre glass moulding as large as possible with a feed from the front.

As a point on driving, it does what it says on the tin. Starts first time, hot or cold. Returns over 40mpg on most drives and i dont think i had less than 20s. Just to add to that, i have fitted a 3.54 diff which helps but did reduce 4th gear acceleration. A quick change to 2nd and away you go, worse things to do in life.

Future proffing perhaps, but im swapping out the twink to put in a zetec. My EFI will be essentialy a direct swap over and the map will only need very slight changes to it, most of that can be done using the wideband function and allowing it via the ecu to make changes to the fuel and ignition settings in keeping with AFR targets.

All in all i think its a very worthwhile conversion and for non purists perhaps the way to go. Prices are very subject to your ability to source parts.


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PostPost by: The Veg » Sat Feb 02, 2019 5:45 pm

How much specialised knowledge is required to get it all dialed-in?
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PostPost by: pauljones » Sat Feb 02, 2019 9:24 pm

By dialed in am i assuming you mean a Rolling Road set up?
That depends in the ecu you choose and if you take it to someone familiar with it.
Id give anyone my map to use, if it helped them.
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