Fitting EDIS to A/C 4.2

awg · October 23, 2017, 12:23pm

The reason I started this as a separate thread is to consider the specific issues of fitting Ford EDIS/Megajolt to 4.2 fitted with PS and A/C.

Rays beautifully engineered kit parts are made for E-types, and the bracket parts not entirely suitable for other models, as he mentioned, so rather than discuss in the E-type forum, I thought it better to start a topic, with various pics, links and questions

The main issue that I can see is that the “best” place to mount the trigger wheel is on the 5" outside pulley, using a 5.125"trigger wheel.

This means the VR sensor bracket will have to be located 4" (100mm) forward of the block

The issue is whether runout in all planes can be maintained to within ~.020".

here is pictures showing the mounting style and position of the VR bracket I would use (example is E-type, pulley is non-standard billet)

and the layout of pulleys on my A/C 4.2…just to clarify, I want to mount the trigger wheel on the front pulley, placing it on the damper would need machining

another lister (Nick J I think) has done conversion on an XJ
here is some pics, (but they cannot all be expanded)

more later…

this picture shows the options

a) in front of 5 " pulley
b) in front of damper requires machining 3-5mm of front of 9" damper
c) rear of damper ( I think this where Ray mounts his)…requires +5mm of machining from rear of damper

it is my understanding the shorter the VR the bracket, the better, in terms of accuracy, in respect of engine vibration

Nick · October 23, 2017, 12:59pm

Indeed the photos are mine. I was the first to fit this to the XK engine and have been running it for about 15 years now. Used a trigger wheel from TriggerWheels.com and made my own overengineered bracket. Still works perfectly.

awg · October 23, 2017, 1:06pm

excellent, it seems you fitted the trigger wheel BEHIND the 5" pulley?

I do not think I can do this, as the 5" and 7" pulleys do no not allow for it, the belts are too close

does your car have the 3 belts for alt, PS and A/C?

aprrox how far does your VR bracket protrude from engine block?

it would be good if your pictures could be displayed in large format…some can, some not

btw, good job and it was your comments in particular in the “performance improvement” thread that got me thinking

Nick · October 23, 2017, 2:24pm

I delved into my deep archives and actually managed to find some photos of this. I’m a little hesitant to show my work in light of the perfectly engineered work on later installations. I find comfort in this being prototype work, yet still in use 15 years later… The first photos show one of my sensor brackets.

Nick · October 23, 2017, 2:25pm

This batch show variant one of the trigger-wheel adaptation (I came up with two, depending on the setup).

Nick · October 23, 2017, 2:27pm

And this is variant two. And, it’s been so long since I did this now that I’m not sure of the details (I think I may be approaching legendary Olde Pharte status). I do have a couple of these trigger wheel setups downstairs though so I may be able to work out what I was thinking.

awg · October 23, 2017, 9:35pm

thanks Nick, excellent.

I do have spare pulleys and damper (and engine) to trial fit

did you have to machine anything?
do you have 3 belts?.. PS outer, A/C mid, Alt inner?

You seem to have located yours in front of the damper, behind the 7" pulley, using a ~7" wheel?
mine doesnt seem to fit there, as the gap is max 8mm

to fit behind Damper would require machine +5mm from rear of damper, (including timing marks)
this doesnt seem good (but might be)

A modified S2 XJ motor is in my 420G, but this is the way most A/C 4.2 are stacked from '66 till mid-70s (that I have seen)

here is a pic highlighting the “gaps” where I may be able to place the trigger wheel, which I assume to be between 8-10mm thick

what I may do is just fit the trigger wheel and sensor 1st and see if that is within spec

btw, imo, your engineering is 1st class, as it should be; simple, reliable, tough, and economical

Nick · October 24, 2017, 6:23am

I’d machine the trigger wheel onto the outside of the first pulley, where the timing marks have been painted on. the trigger wheel is around 5mm thick, put 2.5mm onto the pulley.

Oh, and thanks for kind comments on engineering prowess

awg · October 31, 2017, 1:17pm

I have done a little more research.

It seems to best way is obtain the complete kit from Trigger wheels.com
http://trigger-wheels.com/store/contents/en-uk/p141.html

325GBP = $AU550 = $US425 +P&P from UK

Assuming Ray L is not intending to sell non E-type kits

It would seem the separate Ignition module was only used on certain imported Fodrs, and the common locally-designed Oz 4.0 model had a direct ECU control over coil pack.

As the saving would be ~$100, getting the lot from Trigger wheels would make more sense.

here is a picture of a local Ford Escort, with the trigger wheel mounted out where it would be vert easy to mount on my car
escort 2

I think the most practical method I can take to check vibration/runout is to make the bracket, mount a sharp pencil stub at .040" and see whether the point is damaged

Wiggles · October 31, 2017, 6:31pm

I think that is your best bet. I may do that with the Rover.