I have used them and actually I still have 1 of them on the impossible #5 spark plug that i cannot fit any thing other than a shorty spark plug... I dont care for them the temp range is very limited and I wanted to run a hotter spark plug. But i had to keep the one. When i buy new headers i hope i get a bit more clearance so i can run a full set of my hot plugs.

 

I use them. Have dart angle plug head, and hooker comp headers made for straight plug heads. They are the only thing that fits. As far as I know, they only come in a single "one size fits all" heat range.

 

Used the 0438 for clearance issues only for Dart heads. not performance.

 

I use them on my 302 and they work great. Direct replacement for AC45. Good clearance.

 

They are basically Champion lawn mower plugs that have been relabeled. That is why there is such a limited heat range. If you can not find one on a Saturday afternoon and you need one they are on the peg rack at Home Depot and Lowes. I use them to clear angle plug heads (Victor Jr.) with straight plug headers (Headman) and they work just fine.

Larger Dave

 

http://go.mrgasket.com/pdf/sparkplugs/U_Groove_Specs.pdf

pages 2 and 3, clear as mud their shorty plugs are

kinda hot

I pull my drivers side header out as far as loosed bolts allow, and change my B8ES plugs

 

I found that the NGK plugs were relatively short compared to other plugs.

 

Thanks guys. for the info.

 

The Accel plugs seemed too cold on my old combo and wouldn't work with my new heads. I'm now running the Autolite AR series plugs (AR132's).
They're short like the Accels, have a cut back ground strap, and have a long reach. You'll need to cross reference for you application.

 

I had them for awhile. I didn't have any luck with them in my 327. Car ran bad after a short time. I went back to my Autolites and all was well. Turns out the Autolites cleared my Summit Ceramic coated headers OK after all.