Go Back   Corvette Forum > C1 & C2 Corvettes, 1953 - 1967 > C1 & C2 Corvettes
Sign in using an external account
Register Forgot Password?
Register Search Today's Posts Mark Forums Read FAQ Vendor Directory
Search
C1 & C2 Corvettes
General C1 Corvette & C2 Corvette Discussion, Technical Info, Performance Upgrades, Project Builds, Restorations Sponsored by
Flaming River
Industries

Welcome to Corvetteforum.com!
Welcome to Corvetteforum.com.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join Corvetteforum.com today!


Corvette Store
 
 
C7 Parts & Accessories
C6 Parts & Accessories
C5 Parts & Accessories
C4 Parts & Accessories
C3 Parts & Accessories
C2 Parts & Accessories
C1 Parts & Accessories
Wheels & Tires
Sponsored Ads
 
 
Vendor Directory
  
Reply
 
 
 
 
Thread Tools Search this Thread
Old 02-18-2007, 08:10 PM   #1
Sky65
CF Senior Member
St. Jude Donor '05-'09
Support Corvetteforum!
 
Sky65's Avatar
 
Member Since: Nov 2003
Location: Maryland
Default Which Spark Plugs?

My car is a 65 but I have a 69 350 engine. I was looking at the AC Delco web site and looked for spark plugs by model. A 66 Corvette, doesn't have 65, 327 calls for R45S. A 69 350 Corvette calls for R43S. So. Which plug do I use? I would think the R43S to match the engine. However. I looked the C3 section and the recommended plug there seems to be the R45? Thoughts?
Sky65 is offline   Reply With Quote
Old 02-18-2007, 08:14 PM   #2
MikeM
CF Senior Member
 
Member Since: Mar 2003
Location: Greenville In
Default

Quote:
Originally Posted by Sky65 View Post
My car is a 65 but I have a 69 350 engine. I was looking at the AC Delco web site and looked for spark plugs by model. A 66 Corvette, doesn't have 65, 327 calls for R45S. A 69 350 Corvette calls for R43S. So. Which plug do I use? I would think the R43S to match the engine. However. I looked the C3 section and the recommended plug there seems to be the R45? Thoughts?


R45 or R45S or equivalent in another brand.
MikeM is offline   Reply With Quote
Old 02-18-2007, 09:15 PM   #3
Ironcross
CF Senior Member
 
Ironcross's Avatar
 
Member Since: Nov 2002
Location: Taylor Michigan
Default

Ironcross is offline   Reply With Quote
Old 02-18-2007, 09:22 PM   #4
Mark_Milner
CF Senior Member
 
Member Since: Feb 2006
Default

Quote:
Originally Posted by Sky65 View Post
My car is a 65 but I have a 69 350 engine. I was looking at the AC Delco web site and looked for spark plugs by model. A 66 Corvette, doesn't have 65, 327 calls for R45S. A 69 350 Corvette calls for R43S. So. Which plug do I use? I would think the R43S to match the engine. However. I looked the C3 section and the recommended plug there seems to be the R45? Thoughts?
The original plug for Corvette 327s through '68 was the AC 44. In 1969, it was the R44. The 44 series is not available anymore, but no matter as it was really a bit too cold for normal driving. The 45 series is better.

There is no real performance difference in the 45 or R45. The R is for resistor plugs which help reduce ignition noise in radios. The R45S has an extended tip which helps keep it cleaner from fouling and so it runs a bit better. However, if you have high domed pistons or the heads have been shaved, you could hit. You need to install the plugs, turn the engine over, and then check the plugs if you have any performance work done on the engine.

If you are running the R43S, you'd better be doing hot laps most of the day, because it is far too cold for the street.
Mark_Milner is offline   Reply With Quote
Old 02-18-2007, 09:59 PM   #5
magicv8
9 Hot Rod Power Tours
 
magicv8's Avatar
 
Member Since: Nov 2000
Location: Going too fast over the hill.
Default

The original setup used nonresistor 44 plugs with resistor wires. If you use resistor plugs such as R45, and you have the original Delco coil, IMO switch to nonresistor wires or bag the original and expensive coil.

The original coil is easily overloaded by resistor plugs used in conjunction with resistor wires. So was the Pertronix Flamethrower thatI replaced it with - that lasted about a year before melting down.
magicv8 is offline   Reply With Quote
Old 02-18-2007, 10:08 PM   #6
Sky65
CF Senior Member
St. Jude Donor '05-'09
Support Corvetteforum!
 
Sky65's Avatar
 
Member Since: Nov 2003
Location: Maryland
Default

Thanks
I am using an MSD distributor, 8.5 mil wires, blaster coil and 6al box so I need the resistor plugs. R45S or equivalent it is.
Sky65 is offline   Reply With Quote
Old 02-22-2007, 11:58 AM   #7
JoesC5
CF Senior Member
 
Member Since: Sep 1999
Location: Springfield MO
Default

NGK B4's
JoesC5 is offline   Reply With Quote
Old 02-23-2007, 07:34 AM   #8
paul 74
Ontario, Canada
Support Corvetteforum!
 
paul 74's Avatar
 
Member Since: Aug 1999
Default

I agree with Joe. The NGK B-4 is the same heat range as the AC 45 (hard to find) and is non-resistor and non-extended tip.

Click the image to open in full size.
paul 74 is offline   Reply With Quote
Old 02-23-2007, 07:34 AM
 
Go Back   Corvette Forum > C1 & C2 Corvettes, 1953 - 1967 > C1 & C2 Corvettes
Reload this Page Which Spark Plugs?
 
 
 
Reply

Tags
1966, 30, 327, 350, 68, ac, chevy, corvette, delco, plug, plugs, r43s, r45, r45s, spark, speck


Thread Tools Search this Thread
Search this Thread:

Click for Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -4. The time now is 06:43 AM.


Emails & Password Backup