Basically i have to change the spark plugs in my Classic every 1000miles due to get a misfire feel until car is warm on light throttle, once warm engine all smooth and on boost is all fine. I know this is a plug fault as change them and is all ok for another 1000miles. when take them out all look correct colouring and all same colour.

Always use Laser plat PFR7B, just wondering if I went for more expensive to buy spark plugs ie HKS super fire m series, would I get the same 1000miles before need changing?

Running 1.6bar boost, catch can, mapped etc etc etc.

Also would people recommend changing heat range from 7 to 8?

Cheers

 

something not right there if your changing them every 1000 miles, but you say its fine straight after, are you sure its not a coil pack issue or ht lead breaking up

 

1.6bar+450bhp +75NOS
Thats a fair amount of power mate.

I would talk to your mapper if i was you and take his recommendation.

Personally i would think 8's could be a good move for you. But as said above...

 

Its great fun, spins all four wheels while in motion! Lol

 

You could try an R7434-8 'racing' plug although not cheap at over £100 per set.

I would avoid the HKS plugs as they are just rebranded Denso items, and have been known to crack the ceramic surrounding the tip.

 

 

I have the above mentioned by FBT and were only done yesterday! Give Alyn @ AS Performance a call for pricing as he is v.gd!