Replacement Spark Plugs

[AM04ARO]

The time has come for mine to be replaced.

Had a quote for all 8 - 60k service time.

How much do you think it will cost?

(3 figure time.....)

[ringram]

Dude, save yourself loads and buy some copper equivalents from halfords. NGK.

[alfienoakes]

I was quoted around 17 quid each from Greens. I was so shocked I didn't even ask if that was plus vat. I bought some Denso Iridium from the local parts factor, 72 quid for the lot, and I put them in myself. I did leave a fair bit of skin behind on the engine tho :-( Then I just had the normal 150 quid service instead of 330.

I thought the plugs should be changed on the 50k service ?

Edited by alfienoakes on Tuesday 15th April 08:14

[mobile01]

ive got a set of the denso's spare mate ordered them off sparkplugs.co.uk got 2 sets by mistake doh. £50 if you want them

[ringram]

£14 a set of coppers

[V2RAC]

Champion N5s used to be 2/6d each. Not that log ago. Well bu**er me, I've just realised it's over thirty years. Time has flown.

[AM04ARO]

mobile01 said:

ive got a set of the denso's spare mate ordered them off sparkplugs.co.uk got 2 sets by mistake doh. £50 if you want them

Interested mate - how do they compare with OE? Are they better or worse for a SC car?

[stevieturbo]

People get too hung up on part numbers.....

Ive tried TR6, PFR6B, PFR7B, and now using BKR8IEX Iridiums.


They all screw into the hole, and make sparks I just use whatever I ca get easily, that I fancy at the time.

You do not have to stick with the stupid American tapered seat plugs. Thats just a hassle in the UK, as virtually no cars here use them !!!!

[mobile01]

AM04ARO said:

mobile01 said:

ive got a set of the denso's spare mate ordered them off sparkplugs.co.uk got 2 sets by mistake doh. £50 if you want them

Interested mate - how do they compare with OE? Are they better or worse for a SC car?

work fine in mine wouldnt say they were noticeably better, certainly not worse than the originals as for SC i aint got one so couldnt comment chief

[tim the pool man]

Haven't had to think about them for mine yet, but I assume they are platinum or iridium plugs?
Used to use NGK platinum plugs in the race car, never had to pay for them myself but IIRC they were around $30 each, 15 years ago.

[ringram]

Only reason to waste your money on platinum or iridium is because you want the hardened tip to fall off into your engine, a common complaint. Most performance guys use copper plugs, because they are cheaper and tend not to lose the tip. Though maybe that was earlier versions.

Plat and Iridium are good if you never want to change plugs in the life of the car, but dont give any better or worse spark.

Stock rating is NGK 5's and 6's are good for hotter engines, SC, high compression etc.

Stevie is on 8's by the looks.

[tim the pool man]

Don't know why we used them in the race car, they were supplied by my engine builder, all sponsored. They are the local rotary experts so I guess they had a reason, we used NGK 11.5 and 12.5.

[Boosted LS1]

^ probably because they revved so high they needed a colder plug as it was staying hot.

[alfienoakes]

Are the standard plugs special then? My Iridium Denso's looked the same as the Delco's I took out. I know Vauxhall have your trousers down as soon as you walk into the parts dept, but 17 quid for a copper plug ?

[monkfish1]

The standard vauxhall plug is iridium.

[tim the pool man]

Boosted LS1 said:

^ probably because they revved so high they needed a colder plug as it was staying hot.

Never thought of that, with a rotary each plug fires 3 times per revolution, as opposed to once every 2nd rev for a piston engine. With my race engine revving to 12,000rpm that is 600 sparks per second! (I've rechecked that, it seems unbelievable, but seems to be correct) In comarison a V8 revving at 6,000rpm will fire each plug 50 times per second...

[stevieturbo]

tim the pool man said:

Boosted LS1 said:

^ probably because they revved so high they needed a colder plug as it was staying hot.

Never thought of that, with a rotary each plug fires 3 times per revolution, as opposed to once every 2nd rev for a piston engine. With my race engine revving to 12,000rpm that is 600 sparks per second! (I've rechecked that, it seems unbelievable, but seems to be correct) In comarison a V8 revving at 6,000rpm will fire each plug 50 times per second...

I read recently, and I quote...

[quote]For instance, at an engine speed of 7000rpm, most ECU's can obtain information from between 10 and 30 sensors, process the info, and make a decision about what to do, and actually carry out its command about 40 times before the engine travels through 1 degree of rotation.

Kinda makes the mechanical stuff seem very slow !!!!!