Just curious what spark plug gap you guys are running with his set up? Thanks in advance.

440 around 9.5 to compression and the small summit cam with 915 heads. The cam is like:

Advertised Duration 272/ 282
Duration at 050 inch Lift: 214 int. /224 exh.
Lift .442/ .465 with 1.5 rockers

I'm .035 to .040

Same here. My kid told me about the XR5's and they are about the only plug that doesn't foul out right away for me. I also run around .035 . Combo is 440-6 pack, stealth heads, mild roller cam, yada, yada, yada.

I am currently running a 45 thou gap with my FBO.

I found XR5s too hot a plug in my 440. They were still white after a 1000 miles.

So I fitted XR6s. They came out after another 1000 miles looking too cold.

There is a huge difference in the length of the two plug tips considering they are only supposed to be one step apart.

I may have to go back to using crappy Champions.

i ran mine at .042 then the fbo box went and took a crap..

.040 gap
Delco plugs
stock 318 with FBO and FBO (MP) curved dist.
initial timing is 10 BTDC...
And I'm running the Firecore50 plug wires
Black with straight boots at the plug and cap..
(Very stock looking)

Vacuum is between 22-23" Hg
The highest I have ever seen it
Starts very quickly, Idles very smooth
Runs like a top! - very happy...

I've spoke quite a bit with Don
He's a great guy and his book is a great read

I also did the 2 MAD electrical upgrades
- see www.madelectrical.com

1) Alternator guage bypass
2) Added headlight relays...

Major improvement!

I bought a lot of stuff from MAD over the years.