NGK BCPR6E v BCPR6ES

[Guest]

I need to change my spark plugs. My local MF has both types in stock but before I comite to one type or the other. I would like to know if there is any noticable differance in engine performance between the two plug types. I know the first plug type, ending in "E" is the resistor V grove type and the second plug is the same except for the "S" on the end, which stands for standerd centre electrode. Which would be the best buy?. Oh, By the way my car is a Monty 1.6, F reg, 1988, S-series engine, running on SUL, though it's not had an UL head conversion.

[G Force]

Hi Terry I would say as for performance in bhp terms there will be no difference between the two plugs.

In terms of drivability you may notice smoother running on light throttle with the V groove. I have often had good results curing light throttle shunting by cutting back the earth electrode on standard plugs, and I understand the theory behind the V groove is similar to the cut back electrode. I have not tested the two types back to back but I think you cant really go wrong its a case of you pay your money you take your choice.

Gary

[Guest]

Gforce.

Thanks for the reply. I could not get ether plug today as my local MF is closed half day on Thursday. Anyway, I went to another one, they did not stock ether type of NGK plug, but did offer me an alternetive, ib the shape of the Bosch Super plus + and only £8 a set. The plus bit is that the plug has an YTTRIUM center electrode!. the other differance between these and NGK V groove type is that the side electrode has a small groove cut into it rarther then the center one. I have not tried the car since fitting them. I don't know if you have heard of, or even used them. If not, then i will let you know if I notice any differance in the running and performance of the car with these.

[G Force]

Terry, I cant say I have used the Bosch plugs with the Vyttrium centre, I hope they are an improvement on the ones I have come across which were the triple electrode type. I found these ok when new but once they had done a few thousand miles they were infierior to the ngk's. They gave flat spots and poor mpg, and not to mention fiddly to gap with wire feelers. Even with the gaps set they still needed higher firing voltage and short spark duration compared to worn ngks.

Let us know how you find yours.

Gary

[B18 GPC]

Bosche plugs are generally , very good !

NGK is possibly better though

[Guest]

Hi Terry I would say as for performance in bhp terms there will be no difference between the two plugs.

In terms of drivability you may notice smoother running on light throttle with the V groove. I have often had good results curing light throttle shunting by cutting back the earth electrode on standard plugs, and I understand the theory behind the V groove is similar to the cut back electrode. I have not tested the two types back to back but I think you cant really go wrong its a case of you pay your money you take your choice.

Gary

Gary: My Monty suffers a bit when on light throttle, though it's probably down to wear on the carb. However, just to experiment I'd be interested in knowing a bit more about the idea of cutting back the earth electrode - I've never heard of this before. How much do you take off?

steve H

[G Force]

Gary: My Monty suffers a bit when on light throttle, though it's probably down to wear on the carb. However, just to experiment I'd be interested in knowing a bit more about the idea of cutting back the earth electrode - I've never heard of this before. How much do you take off?

steve H

Hi Steve the theory behind cutting back the electrode for curing light throttle shunting (which is a light misfire giving a very slight jerkiness) is that on light throttle you have a very lean mixture and a lot of ignition advance to compensate for a slower burn rate. Weak mixtures tend to be much harder to ignite than rich ones and with the standard plug earth electrode you can get shrouding & quenching of the spark, this stops the mixture being fully exposed to the heat from the spark in some combustion chambers. By carefully filing back the earth electrode to expose half of the centre electrode you can sometims eliminate some of this, giving smoother drivability due to better ignition of the mixture and without the misfire the manifold pressure stays low giving full ignition advance.

I have had quite alot of success with this method for curing light throttle shunting and it does not affect the life of the spark plug. It is worth a try when you have eliminated all other possible causes of this condition.

Best Regards Gary

[Guest]

Running BCPR6E in my s series with twin dncf's and an ADU 8479 Maestro Turbo ignition ecu, its goes very well with very smooth power delivery

[Guest]

Thanks for the info - it certainly makes a lot of sense. I tend to change plugs pretty regularly (probably more often than I need) so I might try doing this on the old set I took out just to see what happens.

Steve H

[e692wtt]

I've used several sets of Bosch 'Super 4s' in my Monty 1.6L, been quite happy with them. They have 4 earth electrodes and a long centre electrode that projects as far as the earth electrodes. The gap is non-adjustable though, and performance 'goes off' after around 30k or 40k miles.

At the moment I'm using some 'conventional' Bosch plugs supplied by Andrew Page (local motor factor supplier, on a par with Partco) in Fleagle (my latest 1.6L, I know, I know... ) and the engine seems quite happy. The 4 plugs cost me £1.28! I don't have the designation to hand though, sorry. In comparison, the last set of 'Super 4s' cost me around £8 from Andrew Page - still cheaper than a set of 'conventional' NGKs or Bosch from any high street place.

[B18 GPC]

The gap is non-adjustable though, and performance 'goes off' after around 30k or 40k miles.

.

drop them..

30k is a good set of plugs?! !

[Simon]

I've never liked Bosch spark plugs - had a bad experience with them in a Maxi once, so never again! I like to fit Unipart (I know...hit me) otherwise Champion or NGK and I change mine after 12K.

[e692wtt]

I'd say the opposite - I've used Champion plugs and Unipart plugs in my old Mini 1000, not as good as NGK.

In my S-series cars I've used NGK and Bosch plugs, no real probs at all. Had a random, occasional misfire once, on NGKs, a change of plugs fixed that - and it's been Bosch ever since (only because that's what the Motor Factor has in).

[grout20]

Why didn't I read this old thread first!!

Hi all,

I've spent WEEKS trying to cure a "misfire" when driving on a light throttle.

It started when I replaced all Vacuum Pipes, HT Leads, Spark Plugs, Dizzy Cap and Rotor Arm.. like a good owner should!

Just couldn't get it to run as good as before, and even putting Simon Heap under the bonnet a few days ago didn't cure it (but he is an absolute FONT of knowledge on everything that's under there and I now recognise a lot more of the "modern gadgets" under there now.... thanks Simon! )

(My old 1963 Spitfire was MUCH less advanced!)

So I gradually started undoing all the "good work" I'd done previously, and systematically reverted back to the OLD versions of everything I'd renewed .... except of course the damn Spark Plugs!!!

Finally, yesterday, I changed them back... from my nice shiny, brand new, correctly gapped (0.032) Champion RC9YC's .... to the previously fitted NGK BCPR6ES's that had been in there before.

Cured!!

An occasional slight hesitation on acceleration, but this may be due to those original old NGKs gap being set at a whopping 0.072. I kid you not!

The NGK web site recommends the NGK BCPR6E plug rather than those BCPR6ES's, so I've ordered a set of the former.

The site also says the gap should be 0.035 but I'll experiment with a (bit) wider gap in view of that 0.072 gap on the old ones!
Anyone got any recommendations?

I was going to post a thread this morning to tell the story, and THEN I find this old thread which would have pointed me in the right direction without having to spend all my money on my swear box!

Morals of the story....?

1. Have a problem? ..... try searching through MMOC old threads ..... which incidentally Google found, first result, by my search request "ngk bcpr6e vs bcpr6es"

2. NGK's rather than Champion plugs for me from now on!

BTW, mine is a 1991, Montego 1.6 LX, S series, 20,00 miles

If you've managed to get this far down my rambling email, Well Done!

Happy motoring everyone!

John

[E_T_V]

The difference between the E and the ES plug is the supressor built into the plug. I can't remember if you need a supressor but I think most of mine have one.

If you notice interference on the radio then you may need to swap back to supressed plugs.