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2500 6 cylinder megajolt trigger wheel


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Hi all, I've got a Triumph 2000 bitsa with 2.5 engine that I'm having ignition issues with (Optronic ECU packed up, and too much wear in dizzy for points to work well). 

I've used Megajolt for 12 years on my turbo charged A Series Mini, so rather than pay out for dizzy rebuilds or another Optronic, Megajolt is the far better option. I've also got a spare MJ ECU which helps with the cost a lot. 

 

Can anyone share pics their trigger wheel setups on 2.5 crank pulleys please? Looking for inspiration! I know it needs to be mounted to the non-rubberised section for accuracy. 

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I abandoned NGKs some years ago for exactly this reason. Once they’ve got wet they are dead and nothing brings them back. First discovered in a modern (Nissan Primera GT) though I didn’t realise the p

Hi Ian, and welcome. I'm a big fan of distributorless ignition though I've always used it as part of a full engine management system using Megasquirt ECU rather than Megajolt. For both my 2L

Perfect, thanks! All sorted now! 

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Hi Ian, and welcome.

I'm a big fan of distributorless ignition though I've always used it as part of a full engine management system using Megasquirt ECU rather than Megajolt.

For both my 2L engine conversion in my Vitesse and 2.5 engine conversion in my PI I used the trigger wheel sawn off the front pulley from a Sierra 1.8 CVH.  They were very common then, and aftermarket ones rare a relatively pricey.  These days a laser cut wheel will be much easier to find, but the mounting technique may transfer.  The Sierra arrangement did have a handy offset though.

VRS trial fit.jpg

This was the first one, on the 2L  Literally just bolted to the crank with a longer bolt and stepped spacer to hold it concentric. 

timing wheel and vrs.jpg

I did also add a single through-bolt into one of the fan bolt holes to stop it getting any ideas about rotating. The sensor is from a Fiesta with a simple bracket attached to some spare holes in the front plate.  The sensor has to be removed to fit the fan belt.  There was absolutely no chance to squeeze the fan is as well so I had to go electric.

For the PI I did much the same thing, but here the was room to refit the fan so all 4 holes were drilled through the trigger wheel.  That time I welded the sensor bracket to the timing case and the fan belt issue goes away.

crank sensor and trigger wheel.jpg

This works on non-PAS cars.  With PAS it gets more complex and there certainly wouldn't be room for the fan as well.  I sold the car before I solved that one.....

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Thanks for the pics!

I like the second mounting! But, I do have fan and PAS to contend with. Not a lot of room to use there. I think machining the pulley might be the only way but I'm not sure if i can do that without attaching the trigger wheel to the rubberised bit. 

 

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This is on my torsion vibration engine rig, so space not a problem.

1929335781_sensorcloseup.JPG.6a496152659eb2f7e48063ee8dc34544.JPG

This is a different wheel, laser cut from sheet, so that the teeth can be bent forward, over the outer inertia ring, but secured behind to the hub, with countersunk screws.     Takes up almost no space.

DSCF1111.thumb.JPG.171b797b42e045dea93d49ef15b5ae0a.JPG

 

I would suggest that the sensor mount bracket should be as short, and as massive as possible, to avoid any interfering vibration.

JOhn

Edited by JohnD
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The problem on the 2.5 pulleys is that everything apart from the hub, even the pulley, is rubber mounted so anything attached top those cannot be guaranteed to be seeing actual crank position as they will be oscillating about the actual crank position in response to the torsional vibrations.

When the pulley is in good shape, this may not cause enough inaccuracy to matter.  I know some of the A series boys actually get steps machined in the outer ring of their dampers and claim it works fine. The 2.5 ones do sometimes turn though - and then definitely will mess you up!

On the 2L assemblies the pulleys are part of the hub, with only the damper ring weight rubber mounted.

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1 hour ago, Nick Jones said:

The problem on the 2.5 pulleys is that everything apart from the hub, even the pulley, is rubber mounted so anything attached top those cannot be guaranteed to be seeing actual crank position as they will be oscillating about the actual crank position in response to the torsional vibrations.

When the pulley is in good shape, this may not cause enough inaccuracy to matter.  I know some of the A series boys actually get steps machined in the outer ring of their dampers and claim it works fine. The 2.5 ones do sometimes turn though - and then definitely will mess you up!

On the 2L assemblies the pulleys are part of the hub, with only the damper ring weight rubber mounted.

Oh! 

I assume using the 2000 pulley on the 2500 is not possible, or at least is a bad idea? 

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4 minutes ago, Ian2000t said:

I assume using the 2000 pulley on the 2500 is not possible, or at least is a bad idea? 

It will physically fit, though the timing pointer will be rather distant.  I doubt the damper part will function as intended though as resonant frequencies will be rather different.

It's been a while since I looked at this but it's possible that additional pulley tracks (ie ones extra to the basic one formed with the damper ring) as used for the PAS belt actually attach to the pulley hub rather than the pulley/damper ring and are thus solid driven?  All the 6 cylinder pulleys are modular to some extent and it's possible to mix and match parts between them to a certain extent.  Not sure that helps you much......

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So, to pickup on this, it seems I do have a 2000 damper fitted to my 2500 strangely (she is a bitsa!). So, I'll swap that out for the correct 2500 damper.

I've also come to the conclusion that there simply isn't room to have PAS + mechanical fan + trigger wheel, without the trigger wheel being mounted to the rubberised part of the damper.

So, I've ordered an electric fan to fit in front of the radiator. That simplifies the trigger wheel meaning it can now bolt to the (non-viscous) fan mounting bolts.

 

Now, I can't get the EDIS6 unit anywhere, with the connector and a bit of loom. Or the 4 pin Coilpack connector.

Triggerwheels.com will only sell them if you buy a Megajolt package with the ECU, which I already have!

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45 minutes ago, Ian2000t said:

I do have a 2000 damper fitted to my 2500

Is it definitely a 2.5 engine?  95mm stroke rather than 76mm?  I know people who have been surprised before - though usually in the other direction.  Engine No is a very unreliable guide.

May also need to swap the timing chain cover dependent on where the pointer is - or at least move the pointer?

EDIS-6 units were a bugger to find even 15 years ago as they were never common here.  Much more common in the USA but must be getting a bit thin on the ground even there now.  Have you tried actually speaking to TRigger Wheels?  There are several on ebay US right now, some even with the plug

https://www.ebay.co.uk/itm/EDIS6-Motorcraft-Ignition-Control-Module-Megasquirt-Fuel-Management/174542117271?hash=item28a3855997:g:n0AAAOSwleBfxwrM

Your choices are to keep looking or to slightly modify your approach and tweak the ECU to read the trigger wheel and control the coil packs directly.  This does have some advantages but increases the complexity a little.  If you can find a 6 pot coil pack with built in ignitors (easy for 4 pot), it becomes pretty easy with minimal ECU mods but it is also perfectly possible to add ignitor ICs to the ECU.

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20 minutes ago, Nick Jones said:

Is it definitely a 2.5 engine?  95mm stroke rather than 76mm?  I know people who have been surprised before - though usually in the other direction.  Engine No is a very unreliable guide.

May also need to swap the timing chain cover dependent on where the pointer is - or at least move the pointer?

EDIS-6 units were a bugger to find even 15 years ago as they were never common here.  Much more common in the USA but must be getting a bit thin on the ground even there now.  Have you tried actually speaking to TRigger Wheels?  There are several on ebay US right now, some even with the plug

https://www.ebay.co.uk/itm/EDIS6-Motorcraft-Ignition-Control-Module-Megasquirt-Fuel-Management/174542117271?hash=item28a3855997:g:n0AAAOSwleBfxwrM

Your choices are to keep looking or to slightly modify your approach and tweak the ECU to read the trigger wheel and control the coil packs directly.  This does have some advantages but increases the complexity a little.  If you can find a 6 pot coil pack with built in ignitors (easy for 4 pot), it becomes pretty easy with minimal ECU mods but it is also perfectly possible to add ignitor ICs to the ECU.

Thanks - I had seen the US ones, but not the one with the connector. Was hoping to get something quickly!

Yeh, I emailed Trigger wheels - they were very unhelpful:

Quote

We only sell the EDIS-6 as part of our complete packages.  If you are purchasing one of our Megajolt or Microsquirt systems then they include the EDIS kit.

 

Quote

 

We stock the coilpack kits which you can find on our website at http://trigger-wheels.com/store/contents/en-uk/p80.html
For the EDIS module ebay can be a good source.

 

Do you have any info or links on Megajolt driving the coilpacks directly? I thought EDIS was a must for it. I know "Nodiz" can drive coil-on-plugs but that defeats the object of a cheap install because I have a Megajolt ECU spare!

 

Car is a '71 2000, but the engine is certainly a mix up:

MG86 (late 2.5 pi) engine number

219016 "2500S" head.

45D dizzy (late 2500, maybe 2000TC)

Long HS6 Manifold, but with HIF44 carbs (Discovery V8 carbs)

Sump looks to be a deeper 2.5 sump

"CP" TR6 3.45 diff

I haven't taken the head off, but I have tried several times to measure down the spark plug hole the stroke. I always get around 90mm. It's not an accurate way of checking, but I've not got a measurement near 76mm yet.

 

So... can't say for sure, but it's either an elaborate 2000 engine build, or it's a 2500. Surely no one in their right mind would put a 3.45 diff on a 2000 auto though!!

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4 minutes ago, Ian2000t said:

219016 "2500S" head

This strongly suggests 2.5.  You have to be a bit of a loony (:wacko::whistling:hello!) to skim one down enough for a 2L.

The parts listed suggest someone did think about what they were doing though I can't comment on the execution.

Agree on the diff also.

I'll see what I can find on the links.  Do you know which MS ECU you have (MS1 or 2, hardware versions 2.2 or 3?)

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1 hour ago, Nick Jones said:

May also need to swap the timing chain cover dependent on where the pointer is - or at least move the pointer?

Or, bend the pointer - see my second pic above!

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Are people in a rush to get these?

I will be sailing the US West Coast for the next 3-4 months, within reason I can get stuff shipped to a local guy and thus to the ship. I can then bring it back to the UK when I come back, and ship it onwards. Obviously I am constrained by weight on luggage, however I can probably do some EDIS units lol (last time I came back with a set of HS2 carbs and a manifold!!)

Edit: Looking at Rogers links, probably not any cheaper I suspect?

Phil

Edited by thebrookster
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Hello Phil

                  Thanks for the offer but I think I may take a punt on Fleabay at £45 (not that I can test it as the car is still in pieces!) but is the only thing I can not replace easily in the UK

I know they are bomb proof but there is a dud every now and then?

Plus I like to carry the parts that difficult to find! (Spitty has VW/ Skoda coil pack and sensors that are common I do carry all!) but they are cheap!

Roger

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Hello All

               I bit the bullet and ordered one from Ex Trump Land and its on its way and I can get any of the other parts any time here!

Roger

ps that should thwart sods law!

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