Lotus Elan and Lotus Elan Plus 2 Forums

Just curious; if one wanted to do the Jenvey Heritage throttle bodies, or maybe any other FI, do you
really need an ECU?

You will need something to pop open the injectors at the right time. I certainly do not know a system, other than the original Mercedes mechanical type, that does not have a controller

Ok, thanks, makes sense. I know there were a few fuel injection systems before electronics, but I guess
we're well beyond that now

I put a QED set up on my +2S130/5 a few years ago, works extremely well would not go back to carbs
Dvid

gjz30075 wrote:Just curious; if one wanted to do the Jenvey Heritage throttle bodies, or maybe any other FI, do you
really need an ECU?

Here you go - I was idly looking for some info elsewhere and discovered Lucas make one, very much alive and kicking and an injection system of choice in racing engines of the type where they do not worry to much about variable control.

https://www.howacarworks.com/illustrati ... ion-system

Thank you!

Emerald ecu has a loom that works with heritage throttle body available

HCA wrote:You will need something to pop open the injectors at the right time. I certainly do not know a system, other than the original Mercedes mechanical type, that does not have a controller

That and I recall the Spica system that my dad's mid-'70s Alfas had. Totally mechanical, had a little pump that ran via a toothed belt from the crank, and from there it had four metal lines up to the intake, each bent in a 360-degree loop to absorb vibrations. I remember my dad telling me about how the part of the loop where the line overlapped couldn't touch lest the metal rub through. And I remember helping him change the belt one, real pig of a job due to the amount of stuff that had to come out of the way, although that didn't keep him from carrying a spare in the boot.

Late to the party but I was running an old Emerald ECU with Jenvey 45s, a swirl pot and filters (you need good filters) over the diff with a high pressure pump from the swirl to the bodies and a low pressure lifter pump from the tank to the swirl pot - all running my twin cam which constantly produced 150 bhp on the rollers and was a really reliable and very driveable engine.
I used Krontek hardline pipes in the carpet under the central arm rest and everything was plumbed so that if I needed to lift the body, it was an easy job.
It ran an absolute dream so when I decided to change engine to a Zetec I reused the entire installation.
The ecu is really old (M3DK) which I bought second hand and runs the EFI, tacho, rad fan and max rev light (it has a soft and hard rev limit features that I use). The only thing it doesn't do that I might like is to sense the exhaust gases and adjust itself and I think that is simply because I don't have the fittings to accommodate this facility.
I like emerald as a company. Dave Walker is still there with Leoni doing their thing and they really helped me with the initial set up. I put the home pc in the garage, plugged it into the ECU, rang Dave and he logged in using teams, downloaded a map that was close, I ran the engine and he roughly mapped it up to 3000 rpm. I then drove to him (approx 150 miles) and we put the car on the rollers and mapped it properly. It now produces a ridiculous amount of power but very tractably.
I think the only thing I would change is having the swirl pot fitted within the tank which should remove the need for the lifter pump.
The car was featured in Practical Performance Car in the Emerald section of the October 19 edition.
You do need good wiring. Most of the problems are with wiring and interference so I used new wires throughout, I introduced a new supply just for the ECU and separate fused circuits for ignition, pumps etc.
I don't think I would go back to carbs now.
Hope this helps
Gavin

Now superseded by electronic control but the Bosch K jetronic was an ingenious injection system. No ECU here just very clever engineering.

Craven wrote:Now superseded by electronic control but the Bosch K jetronic was an ingenious injection system. No ECU here just very clever engineering.

K Jetronic.jpg

Found on xr3i and 1600i Orion, 115bhp so a good conversion. Used to swap onto kitcars back in the day.

Or if you can find one get an rs 1800 fiesta, full electric control and early ecu was very easy to remap

gav wrote:Late to the party but I was running an old Emerald ECU with Jenvey 45s, a swirl pot and filters (you need good filters) over the diff with a high pressure pump from the swirl to the bodies and a low pressure lifter pump from the tank to the swirl pot - all running my twin cam which constantly produced 150 bhp on the rollers and was a really reliable and very driveable engine.
I used Krontek hardline pipes in the carpet under the central arm rest and everything was plumbed so that if I needed to lift the body, it was an easy job.
It ran an absolute dream so when I decided to change engine to a Zetec I reused the entire installation.
The ecu is really old (M3DK) which I bought second hand and runs the EFI, tacho, rad fan and max rev light (it has a soft and hard rev limit features that I use). The only thing it doesn't do that I might like is to sense the exhaust gases and adjust itself and I think that is simply because I don't have the fittings to accommodate this facility.
I like emerald as a company. Dave Walker is still there with Leoni doing their thing and they really helped me with the initial set up. I put the home pc in the garage, plugged it into the ECU, rang Dave and he logged in using teams, downloaded a map that was close, I ran the engine and he roughly mapped it up to 3000 rpm. I then drove to him (approx 150 miles) and we put the car on the rollers and mapped it properly. It now produces a ridiculous amount of power but very tractably.
I think the only thing I would change is having the swirl pot fitted within the tank which should remove the need for the lifter pump.
The car was featured in Practical Performance Car in the Emerald section of the October 19 edition.
You do need good wiring. Most of the problems are with wiring and interference so I used new wires throughout, I introduced a new supply just for the ECU and separate fused circuits for ignition, pumps etc.
I don't think I would go back to carbs now.
Hope this helps
Gavin

I am surprised you did not include an EDIS into the equation - that and an O2 sensor, you would really be blown away..
Your point about filters and wiring (clean tight connections is spot on. )

Some detailed questions now, for John, Paul and Gavin

I have done the rounds and ending up with Emerald! Spoke with Dave who says that the Emerald should be fine with any French RR operator especially if he has competition knowledge due to the way the Emerald is designed (?). This should be OK, as my friendly chap is an avid drift racer... Dave has offered for him to link up and they can go through it together. He has pretty well sold it to me!

The Emerald kit has the throttle position, air temp and coolant temp sensors as standard, but no MAP or O2.

The Lamda O2 kit is an optional extra (I would have thought an O2 sensor is a no brainer..?).

I know there used to be a convention of using either TPS or MAP, but I thought this had changed with newer ECUs and both were used.

1. What sensore are you all using?
2. I will use Jenvey TBs - do I need the (Dave has it as an optional extra) Jenvy throttle linkage? I thought one used the existing Weber linkage, no?

Thanks!
Hal

Hal,
I am using a TPS, my understanding was that you can use a MAP on an engine with a single TB and is needed on a turbo engine. The problem with using Map on an engine with one choke per cylinder is getting a steady signal.
See the pic in the other thread. viewtopic.php?f=31&t=45894
I am using the Jenvey top mount linkage, it works very well.
Cheers
John

Hal

From my standpoint, the model I have is very old (M3DK) and I kept it simple. I have a crank sensor, air sensor, water sensor and throttle position sensor all provided by Dave. I cheated and bought the ECU second hand and got Dave to put a kit together including a harness, a pair of Jenvey 45s, the link pipe between the bodies, the injectors, pressure valve etc.
I also bought the Jenvey throttle linkage (the above version not the below one) and even the throttle cable. I thought the linkage was expensive but it fits perfectly and is very well engineered so I don't resent the expenditure.
I've shown a picture of the current Zetec and the old Twincam so that you can see how they look.
What I cant talk to you about is the other sensors because I didn't have the opportunity to use them when I started and when I did have the opportunity, I didn't want to mess with the loom I made first time round. Sorry but i cant help you with this aspect but Im sure others can.
Hope it helps - to some degree.
Gavin