Spark Plugs Again
Thread Starter
Racer
Joined: Sep 2001
Posts: 374
Likes: 0
From: Rochester NY --- FL (Oct to May FL.)
Spark Plugs Again
I lost the spark-plug thread from last year and I'm not sure it fit my situation anyway. I have a 64 Vert with a newly rebuilt 365 and running through a 3:55 rear end.
When I accellerate from a stop or at low sppeds there is short lag and I'm leaning towards a plug firing too cold. Don't know how it happened by the plugs i blundered by putting in are A/C 44 S. I kind of remember that most people recommended Some sort of Bosch plug.
Any help would be appreciated.
When I accellerate from a stop or at low sppeds there is short lag and I'm leaning towards a plug firing too cold. Don't know how it happened by the plugs i blundered by putting in are A/C 44 S. I kind of remember that most people recommended Some sort of Bosch plug.
Any help would be appreciated.
Burning Brakes
Joined: Aug 2000
Posts: 883
Likes: 2
From: Hilton Head SC
Hesitation is more likely a carb problem than plugs. I'd double check the accelerator pump adjustment to start. Lots of info in the archives on this procedure. I use R46S's and have zero plug problems with my 365.
Race Director
Joined: Nov 2000
Posts: 10,340
Likes: 664
From: Beverly Hills (Pine Ridge) Florida
Plugs cannot help hesitation. Weak (fouled) plugs will hurt overall performance, but will start showing up at the hi end first when under load (where a strong spark is needed most, but is the weakest to begin with due to decreased coil saturation time).
Really fouled plugs may not even fire the engine at startup (due to shunting/shorting the spark to ground).
Plasticman
Melting Slicks
Joined: May 2007
Posts: 3,461
Likes: 18
From: cooper city florida
I just installed a set Denso w14-u from Rock Auto. These are non resistor plugs and are the same heat range as the AC 45's. They have not fowled with my city only driving,and no problem with radio noise either. I agree with the others,I don't think spark plugs are the cause of your problem.
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I really have had good luck with the Bosch #4236 in my 65 350 horse. It is a 5 heat range plug and it just seems to work better than all of the plugs I have tried over the years. Burns perfectly, starts fast, makes good low end torque and pulls great at higher RPM's. I don't know if I can attribute all that good stuff to the plugs but I'm not changing anything 
Safety Car
Joined: Jun 2003
Posts: 3,596
Likes: 8
From: Grosse Ile MI
43 heat range plugs are probably too cold for street driving a 340 hp car and may cause fouling. I think you would be happier with a 45 or equivalent heat range .