engine miss
Thread Starter
Melting Slicks
Joined: May 2005
Posts: 2,607
Likes: 167
From: sylvania ohio
engine miss
hi we have a 66 coupe 327-300hp 4-speed. it has a slight miss. i pulled plugs and filed and regapped them last week but still have miss but probably somewhat improved. i thought i would try a new set and wondered if anyone had suggestion of a"best"plug for this application,it currently has ac45r [i think]. the car only gets driven about 250 miles a year and in urban conditions,no expressway and no acceleration runs,all mild old man stuff. when i start it ,once or twice a month,i have to pump the accelerator about ten times to get fuel, so it starts way rich. any good advise is appreciated. thanks big cypress
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
Originally Posted by bigcypress
hi we have a 66 coupe 327-300hp 4-speed. it has a slight miss. i pulled plugs and filed and regapped them last week but still have miss but probably somewhat improved. i thought i would try a new set and wondered if anyone had suggestion of a"best"plug for this application,it currently has ac45r [i think]. the car only gets driven about 250 miles a year and in urban conditions,no expressway and no acceleration runs,all mild old man stuff. when i start it ,once or twice a month,i have to pump the accelerator about ten times to get fuel, so it starts way rich. any good advise is appreciated. thanks big cypress
I'd suggest ACR45S or equivalent. If your plugs are gas fouled, cleaning them will not help much if any. While you're fiddling around under there, clean and regap the points and if you have an ohm meter handy, check your plug wires. They may be broken inside the insulation causing your miss.
On your starting problem, I believe the gas is evaporating out of your float bowls. It's common. Try cranking your engine for 15 seconds, stop cranking and pump it twice. It should start. If it doesn't, crank for another 5 seconds and pump the gas again twice. No need to pump it ten times. If it starts up really rich, you need to have your choke adjusted.
It might not be a bad idea to find a young kid on the block that will take that thing and blow it out once in a while.
Last edited by MikeM; Jun 20, 2005 at 09:03 AM.
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
All of my cars have Holleys, and if they sit for 3-4 weeks (or for six months during the winter), fuel evaporates from the float bowls. I add 3-4 ounces of gas through the front bowl vent tube, let it sit for a minute to fill the accelerator pump well, hit the accelerator once to set the choke, and they start instantly. 
