Turbo engines. What spark plugs do you use?

[ITVRI]

I’ve been using a number 6 plug with my turbo install but have recently with warmer weather been getting a bit of light pinking at high rpm at around my max boost of 5psi. After investigating further online and also removing the plugs to see their condition I think 6 is a little to warm for a turbo install and was thinking of changing to at least a 7 or possibly an 8 heat rating. ( which I think maybe a little too cold)
For anyone running a turbo can you advise what plugs are you you running?

[Boosted LS1]

I used to use 7's. NGK

[ITVRI]

Thanks. There are a couple of options
BR7ES or BPR7ES with the protruding tip.
I have also since read in the Lloyd Bros book Tuning and modifying your rover V8 that BPR88ES were recommended for turbo rover engine. 8s seem a little high though?

[Boosted LS1]

Mine were protuding tip. I think it had 'BP' in the part number. Ah, BPR7ES. I imagine those 8's will foul under normal driving so would try the 7's first.

[QBee]

I am still on the BPR6EIX that I ran the car on before the turbo.
I generally use 2.5 psi for road use (325 bhp, 395 torques), with 7.5 psi available for track (395 bhp, 525 torques).

But I can see what you mean, my Saab 2.3 Low Pressure Turbos run on 9s.
And those are tiny turbos, taking the 2.3 litre engine from about 130 to 170 bhp.
I saw the size when I had to replace one recently - it was a sherry glass compared to the TVR's pint.

[Boosted LS1]

^ That seems a bit cold. I'm sure they run on 7's or maybe even 6's. As an aside the turbo's can make mayve 280 hp depending on which turbo it is and other mods.

Which saab did you have?

[Zener]

Run anything colder on the street cooler than a NGK 7 or equivalent and your going to run into fouling issues , 6 or 7 more than capable the cooler 7 depending on boost etc , remember that NGK have a wider operating range than the opposition , and Denso is the only other decent plug brand I would use

[QBee]

Boosted LS1 said:

^ That seems a bit cold. I'm sure they run on 7's or maybe even 6's. As an aside the turbo's can make mayve 280 hp depending on which turbo it is and other mods.

Which saab did you have?

Mine current one is the 9-5 Low Pressure Turbo, 1998-2002 model (chrome grill, leather interior and walnut dash), claimed as 170 bhp.
Not the High Output Turbo, which is claimed as 250/260 bhp.

They drive the same at normal road speeds, so having had two HOT 9-5's I have now opted for LPTs instead.
And for those thinking "why not?" I will add that the older 1998-2002 cars with the walnut dash are far better built than the later cars

Back to the plugs - I will pop out to the man-cave and see what the boxes say. The handbook is a little confusing.

[Boosted LS1]

^ I've had several 9000's over the years but not driven anything newer then 98. They make a very good workhorse. Fastest van in the west to. :-)

[QBee]

Boosted LS1 said:

^ I've had several 9000's over the years but not driven anything newer then 98. They make a very good workhorse. Fastest van in the west to. :-)

Yes, all five of mine have been estates. Nice low tailgates for the dogs.
These days I don't spend more than £1000 on the purchase, and for that you can still get a nice clean car with under 80,000 miles on the clock if you are patient.