Technical Modern Spark plugs Iridium Ford V8 Flathead

I don't think your cap will be as easy as mine was, since mine was an 8BA type.

Also, here's an interesting sidelight for you : I ran marine surface gap spark plugs in that engine and they worked fine. Offenhauser finned heads take a weird length spark plug and the surface gaps came out exactly flush with the inside surface of the head when installed. They are designed specifically for high energy ignitions, so if the Iridiums don't work out, you might try some. I never had a bit of trouble with the plugs on that engine (a 276" Mercury).

 

The plug heat range is determined by the heat at the tip transferring to the core, then through the threads and on into the head and waterjacket. Tweaking fine little details of that path is what the factory does to dial in a particular heat range. Using "spacers" to back an extended plug higher out of the normal heat transfer path will result in fried electrode tips, pre-ignition, and worst consequences. Don't even think about it.

 

So, since it hasn't been ask or stated yet, how many miles / kilometers do you get before the plugs are eaten up?
-Dave

 

Tubman.... thanks for that .., yes it was another option i was going to look at.... i haven’t found it easy to find a site that has all spark plug designs & there specific use etc.... so hopefully i don’t have to do that now... cheers....


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Ok thanks i wasn’t sure about that ... i did wonder if that had a effect on the spark plug..., Much appreciated....


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Buy NOS Champions when I can - ain't hard....run NGK's in my 2 stroke's NOS as I can.....no real issues in 50 yrs or so....yep maybe foul a plug every now and then....detect and change......

 

i remember in some cars i bought there were spacers on the plugs. i was told it was for a cylinder that was fouling out plugs. are they still available?

 

Spark plugs are fun. Everybody has an opinion. Some even have knowledge.
I spent over 50 years behind parts counters, often with a choice of brands to sell.
Listening to all the stories and opinions was always fun, and often contradictory. The old story was that 80% of plug troubles were carburetor. and vis versa. There are no bad brands, just bad mechanics.
A wee while back I installed a rebuilt motor in my 32. real mild, with Edmunds heads and a wee four barrel.
Did many trips up and down a quiet road with a gas analyser while I dialed in the jetting, timing etc.
Started with best guess for plugs, then narrowed it down as the motor told me what it needed, just one step at a time.
Has now done some thousands of miles with never o hint of a problem.
Easy to blame the plugs, but better to understand why there is a problem. Then sort it.

 

Tubman, the spark plugs are closed via the exhaust valve,NOT the pistons on a flathead as you so stated.By the way, pay attention here: My “stupid flathead intakes” are running on a t bucket in Oklahoma and my 32 cabriolet is NOW painted. What else you want to comment on you Minnesota JERK!

 

^ Thanks! That was fun trying to figure out that rant and the colored intake pictures. Delayed retaliation from a 13 day old attack. I’ll check back in two weeks to see where this is going.

 

Don't hold back. Tell him how you really feel !
When I ran the shop for the govt we got all kinds of snake oil salesman coming in . One day a spark plug sales man came in spouting off about his newest and greatest spark plugs telling me how great they were. I won't name the brand so I don't hurt anybody's feelings about their favorite brand.
We had one of the old Champion spark plug cleaners and testers. I put one of his out of the box plugs and turned it up until his plug laid down and started misfiring. We ran Autolite copper plugs in everything. I reached for a used plug on the bench by the tester and ran it through the cleaner to get the carbon off and screwed it into the tester and it was still pulling strong after his $ 6.99 each plug had laid down . At the time we were buying plugs for 99 cents a piece .
I told him that I was perfectly happy with our plugs that we were using and he could take fancy little case he had the plugs in and hit the road.
In the 19 years that I worked there we never had a bad Autolite plug out of the box and we had 900 pieces of rolling stock that I was in charge of .
Iridium plugs were invented so the manufacturers could claim 100,000 miles between tune ups and for emission compliance.

 

WTF is going on here?

 

I’m not telling. It took me too long to figure it out myself.

 

Worked in the parts department at a Chevy dealer in the mid 70's. Customers would come in and buy spark plugs for something like $3.00 a piece. Not sure of the price as it's been 45 years but I would tell them to buy their plugs at the auto parts store down the street for 99 cents apiece. They would insist on buying genuine Chevy parts. I didn't even try to tell them that we bought our plugs from the parts store down the street.

 

Maybe someone is trying to sell intake manifolds?

 

I was looking for a good replacement plug for my used Mercury 2 stroke outboard and was wonder how these NGk (surface gap) plugs would behave in a flathead with an electronic ignition?
@tubman, are you still running these?
Just curious has anyone else tried these?

 

Nope. I have gone to using Edmunds heads mainly because of the superior location of the spark plug away from the exhaust valve. I was able to find conventional plugs that fit those heads perfectly. Plus, the MSD ignition just doesn't fit the theme of an old flathead. An old Mallory "flattop" looks a lot better and works just fine if set up correctly, but probably wouldn't be up to firing these surface gap plugs..

I gave up on Offenhauser heads because of the spark plug location, the problem with fitting the plugs, and the COST. I have had a set of new, unused Offy 8BA heads sitting on the shelf for at least 30 years.

 

Thx tub. Anyone else tried them…..

 

Aren't they easy to change in a flathead?