Spark Plug question
Discussion
I am about to replace the plugs in the HSV and was wondering if there is any difference in the NGK BPR6EF and the AC R41952? Both are listed on the info sticker under the bonnet. AC R41952's are currently fitted and I would prfere to use the same if easy to source.
I have also seen mention of "TR 55 iridium" plugs on another thread somewhere. Are these better than the stock ones listed above?
So, my question is, which are best out of these options and where is the best place to get them from?
I have also seen mention of "TR 55 iridium" plugs on another thread somewhere. Are these better than the stock ones listed above?
So, my question is, which are best out of these options and where is the best place to get them from?
I have had a set of TR55 Iridiums fitted in my Wortec'd 04 CV8. Have always been an NGK man, they seem to last well and self clean in use. The Iridiums are supposed to be better, I think that the idle is smoother with them than it was with the stock AC ones, which suggests that they may perform better right through the range. They are bl**dy expensive, thats the downside. Difference was much more noticeable in my ZZ4 Corvette motor, much smoother.
I was surprised to notice that a mates Monaro listed only Denso plugs when I looked last night.
BPR6EF is equiv to TR6, which is slightly cooler than the TR5 most LS1's stateside use.
The standard tapered plugs, are a bit of an oddity here in the UK. But following from a thread over on LS1tech, I tried fitting a normal plug into an LS1 head.
Ths is with my old 853 castings.
Stock LS1 plug recess is basically flat, with a very slight taper.
Here is a TR6 plug, tightened into that plug hole, as viewed from combustion chamber.
And I was quite surprised when I tried the PFR7B plug into that same hole. I didnt actually think it would have fitted, otherwise I would have just used these plugs in my own engine ( well new ones ) PFR7B is one cooler than the standard double platinum plug as fitted to most Subaru turbos. ie PFR6B
I see no reason why such a plug wouldnt be perfectly at home in an LS1, and I will more than likely be trying a set in mine when its running again.
BPR6EF is equiv to TR6, which is slightly cooler than the TR5 most LS1's stateside use.
The standard tapered plugs, are a bit of an oddity here in the UK. But following from a thread over on LS1tech, I tried fitting a normal plug into an LS1 head.
Ths is with my old 853 castings.
Stock LS1 plug recess is basically flat, with a very slight taper.
Here is a TR6 plug, tightened into that plug hole, as viewed from combustion chamber.
And I was quite surprised when I tried the PFR7B plug into that same hole. I didnt actually think it would have fitted, otherwise I would have just used these plugs in my own engine ( well new ones ) PFR7B is one cooler than the standard double platinum plug as fitted to most Subaru turbos. ie PFR6B
I see no reason why such a plug wouldnt be perfectly at home in an LS1, and I will more than likely be trying a set in mine when its running again.
stevieturbo said:
PFR7B is just an NGK OE number. Double platinum, nothing fancy or oddball about it.
its just a regular spark plug as everything in the UK uses, with the washer, rather than the oddball US tapered plugs.
>> Edited by stevieturbo on Thursday 16th March 17:39
I meant the BPR's Stevie. The insulator looks more into the chamber compared to your subaru plug.
Boosted.
www.sparkplugs.co.uk
just a 'plug' for this web site....
cheap as chips - ordered on line friday 3pm - and arrived saturday morning :-)
result
just a 'plug' for this web site....
cheap as chips - ordered on line friday 3pm - and arrived saturday morning :-)
result
I did a little reading a while back. Denso's are supposed to be tops.
5's for stock, 6 for heads/cam etc and 7's for power add.
You can kind of look at the plugs and do some reading of them, there are a few sites around.
Kind of like light brown or white is too hot, dark black or oily is too rich. Greyish towards black is bang on.
Some after market heads use gasket plugs so best to check, as stevie says stock are tapered.
5's for stock, 6 for heads/cam etc and 7's for power add.
You can kind of look at the plugs and do some reading of them, there are a few sites around.
Kind of like light brown or white is too hot, dark black or oily is too rich. Greyish towards black is bang on.
Some after market heads use gasket plugs so best to check, as stevie says stock are tapered.
Edited by ringram on Sunday 3rd September 19:16
Colour isnt a reliable indicator
Plugs would need to be the ideal heat range, and you would need to stop the car immediately you wanted to actually check the mixtures via the plugs. Otherwise its a little pointless.
And if you are in the habit of using octane boosters, your plugs will be some strange colours indeed.
Plugs would need to be the ideal heat range, and you would need to stop the car immediately you wanted to actually check the mixtures via the plugs. Otherwise its a little pointless.
And if you are in the habit of using octane boosters, your plugs will be some strange colours indeed.
re grade of plug - ie coldness -
in my days of running about in tweeked integrales there was a lot of debate on coldness of plugs in regards to boost level used. What a lot of people forget that on day to day driving without prolonged boost a very cold plug will not get to temp and will cause cr@p running (and stalling/stuttering) from cold start up. so its worth taking into account driving style as well as power to some degree.
colour of plugs isnt as steve says much use - condition in regards to pitting, scale, and burnt electrodes is however.
thing which always concerns me is the preset gap on new plugs? does anyone check them anymore?
in my days of running about in tweeked integrales there was a lot of debate on coldness of plugs in regards to boost level used. What a lot of people forget that on day to day driving without prolonged boost a very cold plug will not get to temp and will cause cr@p running (and stalling/stuttering) from cold start up. so its worth taking into account driving style as well as power to some degree.
colour of plugs isnt as steve says much use - condition in regards to pitting, scale, and burnt electrodes is however.
thing which always concerns me is the preset gap on new plugs? does anyone check them anymore?
Modern fuel injection and proper mixture control, means that you would need to be running 8's, before fouling should be a major concern.
Unless the engine was such a spec, that it required rich mixtures to run in the first place, but there arent too many of them around, at least not LS1's
The TR6's I was using would be more than ideal for virtually any build. I only opted for 1 range colder, as I would be holding the car flat out for longer than I normally like, whilst doing the standing mile.
I would never hold it for that long on the public roads
Unless the engine was such a spec, that it required rich mixtures to run in the first place, but there arent too many of them around, at least not LS1's
The TR6's I was using would be more than ideal for virtually any build. I only opted for 1 range colder, as I would be holding the car flat out for longer than I normally like, whilst doing the standing mile.
I would never hold it for that long on the public roads
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