MSD 8224 and NGK BPR6EIX-11

[stevefh]

Hi all,taken off the original coils with backplate and putting loads of WD40 on the 4 off 5.5 mm bolts so I can separate the fronts from their base plate as the top ones don’t want to move.My questions,  why are the through holes greater in diameter than the bolts and the bottom ones having a metal sleeve but the same diameter,if as a few have stated they earth them to the chassis stud?  Does the small piece of rubber with electrical connector size slits in that comes with each unit fit inside somehow?(not got them apart yet)     I am  leaving the spark plug gaps at 1.1mm ,as they come ,as the higher voltage can account for the increase from .9 -1.0 specified. If it causes a problem NGK tech.service says max recommended gap adjustment is +-0.012” which translates to +-0.3mm so closing into spec.also NGK BPR6EIX opening from 0.8mm into spec.Adjust very carefully without touching the fine iridium tip.Thanks for any help.

[Barrykearley]

You need them backplates or you will get a CEL thrown up.

metal sleeve from memory must be clean and free from corrosion - it is earthed to the chassis.

the coil packs come off the backplates - but don’t break the backplate

[Chillidoggy]

[stevefh]

Excellent picture,thanks 

[stevefh]

Ok,separated the coils from their baseplate.Now I’ve seen mine ,can also make out the pin hole covered by a cello tape like strip on yours.My plate looks glassy black whereas yours looks white/silver,did you clean yours up?What is the plate for/behind it?What is the pin hole? .The 3 holes in the bracket that mounts the coils to its chassis plate are showing a lot of corrosion,is this due to coils action?

[Vulcan Grey]

The spark plug should be NGK BPR6EKN (copper) I know some people like to use the iridium plugs, but I've heard of problems over the years I've been active with the Esprit Delco injected cars...  Besides, it's not the kind of engine that you want to let go 100,000 miles without checking the health of the cylinders by looking at the plugs.

Also with increasing boost, you generally need to go to a tighter spark plug gap, so I'd want to stay within the spec, rather than wider.

[stevefh]

Any comments from those who have used iridium plugs in their esprit?

Edited February 7, 2019 by stevefh

[Bibs]

If you search for 'iridium' you'll find a few threads but none of them extolling their virtues I believe.

[stevefh]

Couldn’t get a nut on the nearby chassis stud. Ground  down its top and wire brushed the thread but it would not take the nuts with two different threads,so gave up the extra earthing.Got the coils from Usautomotive of Bedford via eBay £135 all in.Seems to idle ok.A few days before I drive 50 miles of mixed to set the ecu.Thanks for all comments 

[ragingfool35]

i went back and forth with iridium plugs, really didn't notice a difference (also using PUK's red race chip) but that doesn't mean much.  However when i had my car rough-tuned on dyno after aftermarket ECU and COP, the tuner recommended to switch back to iridium.  I did and it partially smoothed a timing problem i was having. It was tuned to 1.24 bar boost.  It is super crisp and powerful after resolving my timing issue (my homemade cam sensor used a set screw that made the trigger point vary as the shaft it was on floated axially).  I have yet to re-dyno (will inspect plugs then) but have put about 4k miles on the plugs, a lot of them max boosting for "long" periods down the interstate as i fine-tuned the myriad settings.  Data logs (hundreds of them) show no misfires or knock or timing issues with the iridiums.  Doesn't mean they are good or bad or better or worse than the standard plugs, just some incidental data to consider.

when i told the tuner that the Esprit forums eschew iridium plugs, he responded that he puts them in all his cars.  He is a tuner of local renown and strictly tunes Supras and GTRs to 1200 hp.  My Esprit was his first 4 cyl car tune, I had to talk him into it and schedule 6 months in advance.  Doesn't mean his experience with iridium should be taken as gospel, just something else to consider.

[Jacques]

Side question: is MSD 8224 (round or Square one?) the best coil to install in the SE/S4 cars?

Kind regards,

Jacques