Lotus Elan and Lotus Elan Plus 2 Forums

Hi all
For those who are running fuel injection or ignition management, what is the best way of setting up the trigger wheel.
I am running a tooth belt pulley system and don't really want to revert to the QED pulley with trigger wheel cast in because it runs a standard belt and I want to save the water pump.
Are there any alternatives?
Also, where are the sensors located?
Photos would be great....
Thanks
Gavin

Gav

If the engine is out, my way ( adding lightness ) was to drill the flywheel...




with the VR sensor on the closing plate...




very accurate and just how Ford do it ( did it? )

John

Gavin,

I tapped and fixed a toothed wheel to the back of the pulley (toothed wheel from triggerwheels.com for about ?18).

I made up the sensor holder and made the mounting bracket from 3mm dural sheet.

The mounting bracket is semi temporary and I intended to make up something more permanent and rigid - it works fine but there is, I suspect, a bit of flutter at high rpm due to engine vibration and that can upset the signal. QED do one but I am not sure how it fits and whether it will work with my trigger wheel position.

Jon

John,

Could you share the details with us please.

How did you mark the holes?

What diameter of hole?

How deep are the holes?

Why are there two circles of holes?

Did you rebalance the flywheel afterwards?

Regards,

Richard Hawkins

Richard

Yes

Protractor in the centre marked at 10 degrees and centre-punched ( 36 off )
Pillar drill with 1/8" pilot drill
Pillar drill with 1/2" drill with depth stop

Depth of holes 0.277 at centre (drill bit tapered)

After drilling outer ring of holes,decided to follow ACBCs " adding lightness" (and increased surface area for cooling ? ) and did the inner ring.

As for balancing,as the same amount of material was being removed all round, felt no need except for the two conjoined but can't remember what i did about that

John

Thanks for your photos - two very opposite approaches and both well executed.

I want to make this change without removing the engine so am likely to follow Jon's approach as I have a similar tooth drive set up.

I'm not that confident about mounting the trigger wheel to the pulley but the sensor mounting should be ok for me. I think I'll see if I can get another pulley to play with and make the change when I have assembled the remaining components.

Do you happen to know the relationship of the woodruff key to TDC (or am I being ambitious)?

Thanks again
Gavin

Gav.
Mines been done by using a lower front pulley with the pick up sensor as suplied by QED. You will have to ensure you achieve the correct air gap or will work erratically. Found that out the hard way. Ill post pics up later to clarify. What system are you using? Mines emerald and has been rolling road set up.ill gladly share the file if its off use.
Paul

John,

Thanks for the help, were there any other problems along the way with your arrangement?

Richard Hawkins

Richard

Yes,I had the VR sensor wired in reverse,caused little problems in running but when timed with the strobe seemed to retard before advancing...now sorted.

John

Paul,
I have an old Emerald box and am now amassing the necessary components to run it. Spare money for the car is tight and I am thinking about ignition only to start with. I did buy the Aldon ignition pack but decided that if I do decide to go injection, the rolling road time would be wasted. I'll sell it to fund more components.
I think I have sourced another tooth belt crank pulley to play with Much akin to Jon's set up.
My engine set up is essentially fast road (Vegantune) providing max power of around 155bhp and 129 ft lb. How close is this to your spec?
Also, what size throttle bodies are good for torque through the rev range?
And also, does anyone know the relationship between the woodruff key in the crank and Tdc?
Thanks
Gavin

Gavin.
im on memory so forgive any lack of accuracy.
If you going to use the emerald for ignition then you will need a trigger wheel and sensor as mentioned and I think you would use the same coil pack as mine. Its a Ford gen 2 version from a mondeo and also the leads. I think this all comes to around the ?125 mark new. Mines running standard 105bhp but I can still send you the file for reference settings. To make ignition control full 3d you will need a load sensor, normally in the form of a throttle position sending unit.
As far as size goes for TBs, a 2.0 16v zetec will happily run 40mm all day long and still produce more bhp and torque than your spec so id stick to them personally.

Paul

john.p.clegg wrote:Richard

Yes

Protractor in the centre marked at 10 degrees and centre-punched ( 36 off )
Pillar drill with 1/8" pilot drill
Pillar drill with 1/2" drill with depth stop

Depth of holes 0.277 at centre (drill bit tapered)

After drilling outer ring of holes,decided to follow ACBCs " adding lightness" (and increased surface area for cooling ? ) and did the inner ring.

As for balancing,as the same amount of material was being removed all round, felt no need except for the two conjoined but can't remember what i did about that

John

John

I'm intrigued to know how your timing method works. I am not fully conversant with trigger wheel technology but know that the digital electronics side of things copes with (during one rev of the engine) the 'missing' pulse that gives processor a distinct reference. From that reference it can then determine when to fire each spark.

What I dont know is whether all the timing is done relative to that one index pulse or whether it uses all the individual slots or holes of the trigger wheels to fill in the gaps.

The reason I ask is that in your photographs I can see small variations in spacing between the holes and I wondered whether these affect how your engine runs. If all timing is done relative to the double width index hole then maybe the spacing is not important.

How does the engine perform?

Ian

Ian
Correct,the spacing is not that accurate,it just counts the 35 segments but triggers on the missing "tooth", works wonderfully,will probably work better now that i have figured out that the VR sensor was reversed.
Not looked into it too far but it uses other teeth or tooth count as references..

Please see..

http://www.msextra.com/doc/ms1extra/MS_ ... m#Sparkset

John

Jon

Please could you let me know the diameter of your trigger wheel ?

I have done the research and deduced that either you pay a fortune for the QED set up and revert to a standard fan belt or tinker. Whilst the former is attractive because it will work, I am going to need to save money for the throttle bodies etc.so am going to end up tinkering.

I tried to source the manufacturer of my 1" tooth pulley system to see if I could buy a spare crank pulley to play with. I got as far as Titan but they only do the 1/2" belt between the crank and water pump.Units look good and they were very helpful so I will pursue this line of enquiry by checking the compatabilty of the other pulleys. Would love to know who supplies the 1" belt tooth drive sets - life would be so much easier.

Did you have your pulley rebalanced once you added the trigger wheel?

Thanks again
Gavin

Gavin
here's my set up for fuel injection with an Emerald ecu , probably something along the lines you are thinking of

,





Iain