I should keep my mouth shut, but I can't help myself in this case. As a long time straight line racer I can say that indexing does produce results....HOWEVER, you have to have a dyno to tell and at best you might expect to see 1 to 1.5 percent power increase at some PRM range, usually on the very top end. So, on your 300HP engine…you get three extra ponies at 4800 RPM…..it would seem easier to get rid of the mechanical fan or do something like that IMHO.

The story goes, that the plug electrode, if pointed toward the intake valve will yield a better burn…thus producing more power. Published studies show that electrode position on different shaped combustion chambers yielded different results, Thus the need for a dyno. In fact, motorcycle racers have found that pointing the plug away from the intake produced more power on certain engines and it is in motorcycle engines that the application of indexing seems to produce some noticeable results.

Last, to index you need to buy indexing washers. Moroso still makes them and you get about 30 in a set. These washers are tapered to fit the plug seat in order to make a good seal. Last, the heads need to be off to see what you are doing. You can mark the outside of the plug and guess if the electrode is pointed in the right direction….whatever that position might be.

I apologize to those of you out there that think this post has already gone on too long. LOL

 

That's awesome BadDad, I had been kinda looking at the dual point set ups, but just seemed like two things to go bad and replace instead of one. Just got my new Eastwood catalog and they've got the Pertronix set in there for $70 I think, definately worth that, like you said I go through that much in plugs in a years time!! I feel your pain on the mustang, I wish I had it now too! Do you do alot of strip racing with your rigs or mainly cruizing? I'd love to make a pass with mine, just kind of get a baseline performance wise so I can see what future mods do to it. But the nearest 1/4 is about 3 hours away! What have you got that 6000 rpm FE in?

Zeke,
That is music to my ears, I like a simple install and definately love diagrams. Did either of you guys have to do any tuning to the Pertronix after the install or is it for the most part plug and play? I just can't believe that it works that good, but like BadDad said, this would be an upgrade that is worth while and really adds performance!! Oh, thanks to you guys I have given up on trying to index my plugs, I've had my poor truck apart for almost 2 months now and daddy's missing it!! Put the heads back on last night, and yes I did tinker alittle and try swapping around till they all faced atleast a similar direction, no luck!! Hope to get the intake and accesories back on and get her running again tommorrow night!

 

The Pertronix is pretty much "plug and play". It comes with a plastic feeler gauge and you set it and forget it. Make sure you keep the feeler gauge though, just incase you switch dizzies. I am not sure but, I was told that with a magnetic pick up like that you need to use a plastic gauge. If you use metal, you may not get it set correctly.

 

Curtis----- my 390 is in a 68 Merc Monterey 2 door fastback. Got another sitting on the engine stand either waiting for a home or sale, which ever's first. Got parts of 3-4 others. Mine are run on the street, only occasional trips to the strip. JUst don't have time for regual trips to the races. Zeke--------- I've used a regual feeler gauge on mine after losing the plastic one, can't seem to keep track of that little POS gauge LOL. I believe it's something liek .030 thick. No adverse effects from it.