Spark plugs for Turbo

[woodypk]

Hi guys. When I finally get my conversion done, I'd like to know if there is a specific type of spark plug which will give best results. The ones in there currently are cheapish Denso ones but I'd like to treat the car to the best ones I can get especially after fitting the turbo.

A make and model number would be great if you know it off the side of your face....

Ps. Just for my own knowledge bank, If a turbo car has to have different spark plugs what is the reason behind this? - knowledge is power... (turbos are also power....)

[lamcote]

I can't tell you which plug is best but the reason a turbo needs different plugs is because the combustion chamber gets hotter as a result of the engine producing more power, so you need plugs that run cooler, ie they are designed to conduct more heat away from the tip. If you don't run the correct plugs, in the worst case, they could melt.

Obviously you can go too far the other way too, so it would be helpful to know what sort of plug spec the turbo guys/gals do run.

[ChrisGB]

I ran one grade cooler at 10psi boost.

[woodypk]

What do you mean by one grade? Which bit of information on the plug tells me which grade it is?

As a reference, what plugs were you using Chris?

[lamcote]

Standard 1zz plug temp is called 5 by NGK or 16 for Denso. 1 grade cooler will be 6 for NGK or 20 for Denso.
The numbers are in the plug name. The name will also include an 11 but that means a 1.1mm plug gap.

[1979scotte]

As above just run one grade cooler.
Denso or NGK are good plugs.

I wouldn't bother with iridium on a 1zz as they're easy to change unlike the V6 which is a pain.
Which makes it worth the extra outlay.

[wotugonado]

Taken from the tte turbo manual, the recommended plugs have this code
90919-01210

[lamcote]

Looks like Denso SK20R11  or NGK IFR6T11

[Ardent]

All above correct.
I run a tte turbo and run the standard plug 1 grade cooler.
Bkr6 etc etc.
At a smidge over £10 delivered. I change them each service.

[shnazzle]

Whatever you do, don't go higher. Helen's car had bkr7s in it for some reason when we got it and it ran miles better when swapped to the bkr6s it needed.

[woodypk]

Thanks so much for the info guys. I seem to be feeling smarterer every day....