The V8 Owners Forum -

I'm wondering what spark plug heat range you're all using on your boosted Rovers?

I've been using NGKBPR8ES for a few years but they seem to be running too cool in normal driving to & from work, ultimately shorting out on the centre ceramic insulator.
I've bought some 7's but am a little worried they may cause detonation when I do push on a bit.

I use 7's in mine, running about 12lb of boost with no issues

That's encouraging, I run up to 12psi too but my compression is fairly high at 9.7:1..however in reality with the Rotrex your only at peak boost when your about to change gear at peak rpm
I'll fit them tonight
Thanks

I'm using 7's in mine which seem fine although i've only seen upto 7-8psi as I haven't had the balls or space to use full throttle at high rpm yet!

Tom.

7s in my engine too

With good tuning and ignition system 8's should be fine.

Although totally unnecessary, 7's will be perfectly fine. Even 6's would most likely be fine too, although a lot can depend on tuning and usage.