Jump to content
SAU Community

Recommended Posts

Ok guys, please take it easy on this one, I'm new to all this :blush:

I've had a pretty long look through the forums and there seemed to be a lot of dispute when it comes to spark plugs. I've got a stock r34 gtt with cat-back exhaust, what should I be using? I'm not sure what's in there not cos i haven't looked since i bought it (only just read how to), so I'll be having a look this week. There is a miss-fire at idle tho.

So what's the deal? Copper, platinum or iridium? They last different amount of time, right? I'm trying to learn as much as i can at the moment so i don't mind changing the plugs every 5000km with oil (also changing that this week cos, its been almost 7000km and starting to hear a bit of ticking, hoping the change will fix it).

I understand is like this: a certain voltage is sent through the plug, which causes the spark, so smaller gap means the spark happens earlier in the piston cycle (as wekk as being more consistent as less spark is required). Copper requires less voltage to cause the spark (ie more consistent between cycles?), but due to the properties of copper some of the spark plug is lost during each spark. Platinum and iridium are much harder and thus so they don't erode as quickly. The erosion affects when in the cycle the spark fires because it changes the plug gap.

So, please correct me if this is wrong!! And what do i buy? lol

Thanks in advance

Link to comment
https://www.sau.com.au/forums/topic/312822-another-spark-plug-question/
Share on other sites

cheers mate. what a fantastic thread, pity im so confused tho. everyone seems to have a different opinion and with such a range of engines and mods no-one's talking along the same lines.

kinda wishing id searched the forced induction performance thread, not just the maintenance one :$

thanks again

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • You’ll want to have the block drilled and tapped to suit 1/2in head studs and the head for the same. How much power do you intend to make?
    • Sorry for resurrecting an oldish thread Not much has happened in the past year since the last update. The car did another 1000 miles or so and failed the MOT for the first time in October (failed on tyres which had been advised for a couple of years) In October the car got put up for sale and was removed in November due to no interest, being so close to christmas it was to be expected. The roads were dry in February so I decided to tax it early and get the new tyres fitted.   Fast forward to April, I got someone in to give the car a good clean after sitting for the winter.                                 The car got re-advertised and today (Saturday 3rd May) the car sold. The new owner is planning a GTR conversion at some point and a respray in the same pearl white. It's bitter sweet, it's a shame to have the car sit there for half the year and then only do 1000 miles. The kids are growing too quick and space in the back is getting limited. It's been a great 6.5 years of ownership
    • And if you want more power, more reliably, and cheaper, go get the Aussie RB... The 4L Barra and put that in instead.
    • No cats will keep discolouring the rear bar. Sends white paint a weird yellow stain. Cut and polish normally gets it out, but you'll be doing that every fortnight I found.
    • Both heads will be equally reliable or unreliable depending on what you do to them.  Stock the RB26 head will flow more. You have access to the stock intake ITB manifold on the RB26 cheaply which flows really well(1000hp+).   Arguably more aftermarket support for RB26, though in Aus we love our RB30 SOHC heads too.    The only downsides to the RB26 head is if you have a VL commodore and want to keep the SOHC look.  Where you may have an issue is drilling out the rb30 block for the bigger head studs but if you are building a big power motor you'd probably put bigger studs on the SOHC head too.  This is just about finding a good machine shop, sometimes easier said than done.  RB30 head worked can make big power just like a Rb26 head, so really it actually more comes down to what your preference is for your car.  People now even making billet versions of both.
×
×
  • Create New...