Rover V8 and spark plugs

[Hybrid_From_Hell]

Hi all,

For Rover V8 owners some info that may or maynot be 100% correct, but

is my personal view of a problem I have no had for a second time

I know and many also agree the plugs a V8 Prefer over most other is NGK, and V8 Rovers

do not like 4 prong specials and defo not Champions for some odd reason.

Well, I seem to have another "Oddity" now....

The Eales has been getting worse to start, again, . Not that long ago (5 months) I shoved yet

another set of new plugs in BCPR6ES and the engine was much happier. In the last 3 months

the engine has been yet again becoming a pig to start - worse as it gets colder.

Yesterday it fired, ran stalled and flooded, and flooded "Big Time" left over night

when I tried again did the same, I thought it was due to the start up WUE and ASE settings

in Megasquirt being "Wrong" since fitting the new chav exhasut so spent most of today mucking about

with the start settings and whipping plugs in and out - no joy.

For some unknown reason I decided to shove the original (Yesterday) settings in the ECU and a set

of new BPR6ES plugs - fired 1st turn.

So, thats 2x sets of BCP NGKs in 10 months

A few phone calls to those I deem experts have resulted in "Ah...Fit BPR6ES and NOT BCPR6ES" as they don't seem to

be as tough....quite a few have done what I have and gone back to BPR6ES, I shall make a note to report back in 5 and 10 months

on the starting situation - this is STARTING once running all was well, but yesterday wouldn't even start

Odd, but thought I would share my views on this...

Anyone else come across this on the Smaller headed C type plugs ?

Nige

[mickeyw]

Been using BPR6ES in various Rover V8s for many years. Never had any trouble from them, even LPG likes them so they must be good.

Any running problems have always stemmed from crappy cheap coils.

[TheRecklessEngineer]

I haven't quite got as far as worrying about my plugs yet...

[disco_al]

I have had BPR's installed in mine since Feb/Mar this year (they do need changing i think now though) with no problems, until the cold weather started. most mornings it would not fire, so i got into the habit of switching back to petrol as i pulled into the end of the road, and that seemed to help a lot.

The only difference between the BCP and the BC is the size of the plug spanner - the rest of the specs are the same.

On a side note, NGK do make a specific LPG plug for the V8's, but at about £15 per plug (last time i checked) compared to about £1.20 per plug for the BPR's - i would rather change them more often than fit fancy ones.

Can't see the size of the hex making much difference TBH, seems strange that this would make so much difference??

[MJIbex]

I always used to use the NGK BPR6ES with no problems except once when I got 1 dodgy plug in amongst the 8 which begun to fail after not very long causing an ocassional misfire.

The whole lot were changed and that was the end of it.

Mark.

[bobtail84]

Im you brought this up Nige as Im having troubles with my 4 prong bocsh plugs so Ive changed them for bcp6es and then have bad starting AND when on gas it blew the snorkle pipe to bits when cold.....

Jeff.

[Hybrid_From_Hell]

So, just how much do you now hate me

Tangoman had these,

and they drove him mad until he went BPR6ES NGK,

.....thats of course before he moved across to the truly 'dark side' <diesel shudder> of the 4x4 force

Nige

[Hybrid_From_Hell]

Can't see the size of the hex making much difference TBH, seems strange that this would make so much difference??

Yep thats exactly what I thought - I am told by 'gurus' that on a 'high comp' or 'high spark' outputmotor the 'C' type

plug vs std can have trouble dumping the heat and as such BPR6ES are a better and more robust buy .

As I have both high comp (around 11++:1) and high spark (Ford packs make you go Ooooooooooo when touched)

I think they may be right, there was no sign of errosion wear or damage on any of the old C plugs

BUT..2x sets of 8 NGK 'C' type plugs in 4 and then 5 months is at best odd, lets see what a new set of

std BPR6ESs do in say 6 and 12 months.

Nige

[bobtail84]

So, just how much do you now hate me

Tangoman had these,

and they drove him mad until he went BPR6ES NGK,

.....thats of course before he moved across to the truly 'dark side' <diesel shudder> of the 4x4 force

Nige

I dont hate you but I will bring all my spare turkey round so you can enjoy it for a second time... with the spare soggy yorkies...

[paintman]

Was an article in a Trade Mag a while ago by NGK which said that the fitting of multi terminal plugs in engines for which they are NOT original equipment is not recommended. Can't remember what the reason was.

[Hybrid_From_Hell]

Was an article in a Trade Mag a while ago by NGK which said that the fitting of multi terminal plugs in engines for which they are NOT original equipment is not recommended. Can't remember what the reason was.

Prob something to do with the shaping of the combustion chamber

Rover V8s have an old fashioned 3 wedge shape which may not be what they need to work well

Nige

[Young bobtail Rhys]

It is weird that you say Nige that champion don't seem to work I have had champion triple silicone leads on for over 3 years now (were fitted when we bought it). How many problems?????..........None! Thanks to me trusty lunch box sealing the coil, I can happily pressure wash the whole engine at every angle, and it still either keeps running or starts first time

Anyway, back on proper topic

[Bill Shurvinton]

Plugs can be funny things. Given their only job is to create a spark kernel all sorts of odd things can happen. Given that Nige is running a somewhat breathed on motor it could be that perhaps the current plugs are too hot and 7s or 8s would be better.

Also the EDIS gives a big, fat spark (I think you had a bit of electro-convulsive therapy off if once Nige?). If the gapping is sed for a weedy dizzy setup then you will chew through electrodes.

Sadly unleaded makes reading plugs a bit less interesting than it used to be, but a close up pic of the old ones might give a few pointers.

[Escape]

Very interesting topic Nige! A few weeks ago, my rebuild 4.6 died on me. After being outside in freezing temperatures for a few days, it fired up staight away, ran rough for a few seconds and then died. All attempts to get it to start since have failed. But I did not change the spark plugs, as they were only a few months old and seemed to give a decent spark. Yes, they are NGK BCR6ES, and the engine has a slightly higher compression...

Can't get hold of a set of BPR6ES any time soon, so I'm gonna try Champions today. They seem to work very well on my mates 3.5.

I'll make sure to keep you guys updated!

[Escape]

I just fitted new plugs to my V8, and yes, she's alive again!

I just love this forum. B)

[ThreePointFive]

Is this mostly to do with megasquirted engines? My completely standard 3.5 has been running on Bosch plugs for about 5,000 miles and they seem to work fine. Oddly enough Paddocks sell the Champion plugs as part of the recommended service items for 3.5s. I know Paddocks is a bit like going to PC world for IT advice but they must work? As an aside, how often should plugs be changed?

[bobtail84]

Plugs can be funny things. Given their only job is to create a spark kernel all sorts of odd things can happen. Given that Nige is running a somewhat breathed on motor it could be that perhaps the current plugs are too hot and 7s or 8s would be better.

Also the EDIS gives a big, fat spark (I think you had a bit of electro-convulsive therapy off if once Nige?). If the gapping is sed for a weedy dizzy setup then you will chew through electrodes.

Does anyone have any suggestions as to how much gap I should have on my plugs? I've got them gapped to 25 thou at the mo and i'm MS & EDIS also LPG.

[woodytz]

Does anyone have any suggestions as to how much gap I should have on my plugs? I've got them gapped to 25 thou at the mo and i'm MS & EDIS also LPG.

gap them to 0.75/0.80mm or in old money bout 35 thou, change em regular if your doing the miles or when they muck about

[FridgeFreezer]

All V8's I've known are fussy about plugs - my RR was flat dead not even a cough when I got it, changed the plugs and it roared into life sweetly.

I suspect EDIS will show up weaknesses as the sparks are massive compared to the pathetic stock setup, for gaps I'd look at whatever Ford do on their EDIS motors (Escort/Mondeo/Fiesta/etc.) as a starting point.

[bobtail84]

I suspect EDIS will show up weaknesses as the sparks are massive compared to the pathetic stock setup, for gaps I'd look at whatever Ford do on their EDIS motors (Escort/Mondeo/Fiesta/etc.) as a starting point.

Ford recommend 1mm for the NGK.... best I whip them out so too speak..

[Escape]

Is this mostly to do with megasquirted engines? My completely standard 3.5 has been running on Bosch plugs for about 5,000 miles and they seem to work fine. Oddly enough Paddocks sell the Champion plugs as part of the recommended service items for 3.5s. I know Paddocks is a bit like going to PC world for IT advice but they must work? As an aside, how often should plugs be changed?

My 4.6 runs the standard GEMS system, previously with NGK,now with Champions, and had the same problems as Nige's V8.

My mate uses Champions in his 3.5 EFI on LPG and is very happy with them.

[Guest weeble]

Try using the non resistor ones i.e NGK BP6EVG. These were developed for LPG systems and are single electrode with a V groove to give a more concentrated spark.

We used to fit them to all V8`s when we did LPG conversions and found them to be very good. I still use them in my LPG powered V8 and they have been excellent.

[Quagmire]

Another vote for the V-Groove NGK's when running LPG here too, i had them in my 2.25 and it ran perfectly. More importantly, it ran perfectly all the time... No noticeable difference in smoothness, no hesistation.

I currently have Champions in the v8 and that doesnt seem to be anywhere near as smooth so far even with the extra 4 cylinders, although saying that it hasnt let me down or anything- yet. (touchwood)