Spark Plugs for 65 L79

[Sheldon S.]

ould someone please tell me what the correct originl spark plug for a 65 coupe withe the L79 350 HP motor with no A/C and a 4 spd is. The judging manual only says that AC plugs were used. Do you not get any deduction for using new AC replacement plugs or should a peson have originals?
Thanks in advance.
Sheldon

[Joe C.]

Re: Spark Plugs for 65 L79

Sheldon:

As I understand it, you will get a deduction for non original type spark plugs, even though it is not specified in the TIM&JG. The owner's manual specifies AC 43,44, or 45 plugs, depending on usage. I installed the 44's (non resistor type)in my 1965 L76. Some folks prefer the 45's, but my assumption was that the car was delivered with the middle heat range plugs (best for all around use).

Joe

[Gary B.]

Re: Spark Plugs for 65 L79

Sheldon,

If 65 L79's were like 66 L79's, then I think AC44 were the original plug. Most people say that L79's run better on AC45. I'm not 100% certain, but I don't think judges can see what type of AC plus one is using when the ignition shielding is installed, so I would go with a plug that makes the car run well.

Gary

[Joe C.]

Re: Spark Plugs for 65 L79

Gary:

I can read the plugs (depending on their orientation) by looking down thru the top between the block and head. I can distinctly see "44", with some orange overspray.

Joe

[Joe C.]

Correction

I meant to say "between the heads and exhaust manifolds", not "between the heads and block".

Joe

[Duke W.]

Re: Correction

All SBs run better with AC heat range "5" or equivalent but all C2s were originally equipped with AC 44s, and as you say, you can see the markings on the insulator if you know how to look for them, and most judges certainly do.

duke

[Duke W.]

Re: Correction

I meant to say that all SMALL BLOCK C2s (regardless of power rating) were originally equipped with AC 44s.

Duke

[Sheldon S.]

Re: Correction

My car has the radio option, should it have the resistor plug or did GM use them back in 65?
Thanks
Sheldon

[Duke W.]

Re: Correction

All C2s had non-resistor plugs from the plant. I can't remember the year that resistor plugs became standard, but it was late sixties to early seventies. The RFI suppression wires, along with all the ground straps and shielding should provide static free radio reception.

A lot of guys are running resistor plugs - apparently with no ill affects - but they probably dissipate additional ignition energy, and the single point system has little energy reserve to begin with, so my choice is non-resistor plugs as long as they are available.

Duke