Spark Plug Gap

[lotusdelta]

i wonder if anyone could help with the correct plug gap settings for a 1972 lotus elan sprint coupe.
i am using ngk-bpr5es plugs and was told that the plug setting should be .025-.028. however ,the manual says .020(non-emissions-.025 for emissions models any thoughts?
. my elan is a us federalised model
thanks everyone !!

[gjz30075]

With the age of our cars now, emmissions vs. non-emmissions is pretty much a moot point. I run the exact plug in my 1720cc motor, with a sport coil and I run .028 gap with no problems (related to the gap, that is).

Greg Z.

[worzel]

Hi

In a UK standard spec Sprint I use BPR7ES with a gap of 25 plus a sports coil and Lumenition.

Incidentally (and I'm not too clever on this on US spec cars) aren't your plugs too hot.

John

[lotusdelta]

hello evryone, thanks for the input.

john in regards to how hot the plug is, i was advised that the bpr6-es was too hot and the ngk bpr5es was more appropriate....hmmmm..... anyhow this was from dave bean in calif.
thanks, david

[dlbarnes1]

As I recall, the heat range on NGK plugs has the number increasing with colder plugs, just the opposite of Champion sparkplugs. And, this is generally indicated in Bean's catalog.

David - 72 Sprint DHC

[types26/36]

For some NGK spark plug info go to:
<a href='http://www.ngk.com/sparkplug411.asp' target='_blank'>http://www.ngk.com/sparkplug411.asp</a>
Go to NGK on left and follow the thread.
Brian.

[lotusdelta]

hi everyone,

thanks for the suggestions.....seems i might need those reading glasses after all .... as i reversed the plug size and am actually using
ngk-bpr-6es plugs for my 72 elan sprint.......

thanks david

[worzel]

The comment about heat range numbers on NGK plugs is correct- BPR6ES is equivalent to Champion N9Y (fairly hot). The bigger the number the colder the plug

John

[Speedster]

Hi what are thoughts on using NGK BPR7ES on my big valve head and Weber’s using Alden electronic ignition and coil and gap on plugs of 0.025

[richardcox_lotus]

I used to find that when running NGK7’s on my sprint, they would foul when stuck in a traffic jam for about 30 minutes or so. If running non stop Motorway journeys they would be fine, but I switched to 6’s and had no further problems.

[69S4]

Hi what are thoughts on using NGK BPR7ES on my big valve head and Weber’s using Alden electronic ignition and coil and gap on plugs of 0.025

Any particular reason for using resistor plugs? I've always kept the resistance in the leads or in the caps and used 'normal' plugs but that's been with points. Heat grade - I've always used '7's'. I've had a few foul in really awful traffic (idling for 2hrs+) but mostly they've been spot on.

[andyelan]

Hi Everyone
I've always used non resistor NGK plugs (6 or 7s) in my Plus 2 and Europa Special but find they're becoming increasingly difficult to find nowadays. BP7ES seem to be still available ok but generally only from more specialist outlets.
Andy

[Hawksfield]

Hi
Just got a new set of bpr6es off Ebay checked for being copy and are ok they come gapped at 1.0mm which I use with high output coil. no problems.

[h20hamelan]

resistance plugs and wires for electronic ignition?

[Davidb]

As 20hamelan says-electronic ignition (Pertronix and Alden anyway) seems to require resistance plugs and leads. Pertronix states-in Red-on their website that resistance leads are required but the Twin Cam has short leads and resistance plugs help--that is according to Keith Frank and I, for one, will acknowledge him as an expert!