I know there is alot of info on the site regarding plugs but I still have questions

 

The standard spark plug heat rating for the TT is 6 right?

 

When you increase boost pressure along with adequate fuelling you increase BHP. The purpose of a colder rated plug being to remove the extra heat created by the higher performance from the cylinder quicker right? So at what increase in boost/bhp do you move up to 7/8/9 etc?

 

From what i've seen there are three options of manufacturer: NGK, which seem to be the most commonly used by Z32 owners - HKS, which are bloody expensive - Denso, that i've been told make alot of HKS plugs but are alot cheaper and have a different heat rating system.

 

Is there actually any difference between them apart from price?

Do we need Iridium electrodes and is it a case of the smaller the tip the better?

 

Cheers guys

IMHO Matey, colder rating plugs need to be in a cylinder that is at full optimum temperature, I.E. on a track, or thrashing its ass off....lol

 

plugs rating at 6 is fine for standard 300's and uprated 300's.....

 

Alz.

 

And stick with NGK..... :)

IMHO Matey, colder rating plugs need to be in a cylinder that is at full optimum temperature, I.E. on a track, or thrashing its ass off....lol

 

plugs rating at 6 is fine for standard 300's and uprated 300's.....

 

Alz.

 

And stick with NGK..... :)

 

Yup - stick with that advice Scot; you can't go wrong there matey!

 

Richard:yes:

Cheers guys, still interested in more info on this if anyone has any? The standard plugs are platinum right? Any benefit of iridium and what's the deal with the electrode diameter?

the ngk plugs that were fitted rom factory where actually specifally designed for the zed. so its best to stick with them theyre was alot money put into getting them right. most find there is no need for cooler plugs this side of 450bhp. there was a recent tread carmad had going where he was running 555 injectors without the cooler plugs it just didnt work right.

Cheers just found it. Im asking more for the knowledge than anything else, last time I lived in the UK and was into modded cars it was all about the twin ground spark plugs if you remember them lol

I have one grade cooler (7s) ngk iridium plugs and im running 14psi boost with a central20 ecu with a dta chip and e.b.c and it runs sweet as a nut.got them from conceptua and were cheaper than I could get stock plugs for.