Just about all the parts stores I've been to carry the 3924. It shouldn't be a problem. Just ask for the plugs, don't let them try to ask for the application... I've never understood why they insist on knowing what car it's for. I would have been glad to have someone walk in and ask for a specific part number when I was working parts. It's like they can't figure out what to do if the little computer screen doesn't tell them.
FYI, the difference between the #24 and #3924 is the seat (tapered or gasket). The #24 (25, 26, etc.) have a tapered seat, and are usually used in iron heads. The #3924's are identical to the #24 except that they have flat metal gasket. This type of plug is usually used on aluminum heads.
Autolites are designed and manufactured to and for chevy specs. besides these plugs are garbage!!! if you want good plugs then get the denso iridium plugs. i dyno'd my car with Bosch platinum 4 plugs, changed the plugs, then dyno'd it with the densos and got 8 HP, on plugs and octane booster. Bosch 4s are better than the autolites, but if you wanna just go cheapy than its up to you!:evil:
Hmmm, that's odd. It happened to me the other way around. Used the Bosch +4 plugs(4 damn dollars a piece!!!) and fouled them on a single dyno run. Slapped in some Autolite 3924's (89 cents a piece) on the same tune and picked up 7 HP.
Well it's not surprising that Bosch 4's gave a lower output than the denso's. What you're saying about Autolite is a figment or your or someone else's imagination. Platinum plugs have long been known to not perform as well as a more thermally conductive plug, like copper or silver. Don't know the thermal conductivity of iridium off the top of my head...
ok, lets assume for a minute your not full of sh**, the 4 bux a piece plug is 32 bux for a set, and i change plugs twice a year, or about every oil change, ~600-800 miles. so i spend 64 bux a year for these bosh plugs, for a theoretical 7hp?? no thanks.
now, i pay about .69/per plug for the 3924's, as i buy them once every year or so when there is a great deal on them and stock up (i have about 6 sets right now) so i pay less than 12 bux a year for my plugs, and you want me to pay 64 bux...? again, no thanks
i guess next youll tell me synthetic oil is better because gas milage is 1 mpg better? yet it costs 4 dollars a quart more, so the net savings there is like -50 bux a year or so.....
i can find 7hp all over the place, most could on a street motor, just by keeping your car in tune will keep my 7hp over a year, where youll drop off 10-15 letting your cap get corroded, or not changing your plugs as often...
not to mention the fact that silver is the best conducter known to man, and copper is not ALL that far behind...as billy said about irridium, i have no idea of the electrical conductivity, but arent they like 8-10 bux a plug? lol
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more!