Ignition: R2 plug selection

[63 R2 Hawk]

I am looking for spark plug & gap recommendations for my '63 R2 Hawk. Not "this or that brand is junk" comments, but input based upon your own personal experience with a similarly built engine. This motor is bored .030", b&b with Erb pistons, cam and supercharger with R3 style intake and exhaust headers feeding 2 1/2" pipe. Compression ratio is ~9.25:1. Ignition is Pertronix with locked advance. Spark is MSD 6AL with an MSD 8981 timing computer and Taylor wires. I try to burn non-E 92 octane or 100LL avgas as much as possible, otherwise it gets so-called "premium" pump gas when I'm traveling or broke. I am currently running Bosch WR9FP platinum plugs gapped to .045 and I don't have any particular complaints, they show decent burn patterns and have never failed, glowed or blown the porcelain out but MSD does NOT recommend specialty, "hype" or platinum plugs and I have always had trouble getting it to run when timed correctly, I always end up tweeking it. Thinking about trying Champion J12YCs which, IIRC, is one of the few non-resistor plugs available these days. Would this be a good plug for this engine (since I already have a couple of sets of them)? Any better recommendations?

[SN-60]

To: 63 R2 Hawk,----- All I can tell You is that I've used Champion J12YC's in My stock '63 R2 for years with no plug problems whatsoever.

[DEEPNHOCK]

Well..... Your engine is not stock, so toss the stock book and mindset away.
You are doing the right thing by 'reading' your plug(s).
If they read 'good'...Stay there!!!!!
If they read cold, up it a heat range until they read 'good' (and go down if they read 'hot'....
Small changes...
Question...
What does your carb tell you?
(Seat of the pants, economy, operating temp????)
Make sure your A/FR ratio is good with your carb before you start changing heat ranges.
An excessively rich carb cannot be corrected by putting in hotter plugs.
(and vice versa).
Get your a/fr ratio within the range and then tune the heat range on the plug.

I am sure you will get a variety of answers to this question (which is a very good question...)
Jeff

To: 63 R2 Hawk,----- All I can tell You is that I've used Champion J12YC's in My stock '63 R2 for years with no plug problems whatsoever.

[bezhawk]

I was going to suggest Bosch WR9FP's....go figure.

[63 R2 Hawk]

I haven't thrown the Bosch plugs under the bus yet, but the MSD folks are pretty adamant in their stand against what they call "hype" plugs, including platinums. They recommend copper, period. I think I'll try the Champ J12YCs since I have a bunch of them already and I'm due for new plugs anyway.

[KOOL R2]

On my Avanti R2 I am running AC 43S plugs. They seem to perform best even on the dragstrip.

Peter Sant