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Feb 27, 2011 | 06:04 PM

Johan74

Thread Starter

Racer

Joined: Jan 2007

Posts: 308

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From: Sweden

Spark Plugs...

For a 69 SB (350hp)...

Zip says R43S
Paragon Corvette Reproductions says R45
and my Haynes manual says R44

Who is correct?

Feb 27, 2011 | 07:05 PM

capevettes

CF Community Team

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From: Cape Cod, Mass.

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R45. For a street driven Corvette the 5 heat range is the way to go on both big and small blocks

Feb 27, 2011 | 08:10 PM

SoCalErv

Burning Brakes

Joined: Oct 2006

Posts: 1,089

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From: Native Californian CALIFORNIA

Army

The NGK B4 and Denso W14-U are non-resistor plugs of equivalent heat range to the out-of-production non-resistor AC 45.

Feb 27, 2011 | 08:31 PM

Lemans Blue 69

Racer

Joined: Jan 2010

Posts: 348

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From: Lowell MA

Use AC44S or equivalent. Bought some on ebay. Gap at 33 vs 35 and set dwell to 32 vs 30for best performance.

Feb 27, 2011 | 08:33 PM

Mike Ward

Race Director

Joined: Jul 2001

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For once the Haynes manual is correct, problem is that R44 are out of production and very hard to find.

I like the NGK B4 like Erv mentioned.

Feb 28, 2011 | 12:35 PM

Johan74

Thread Starter

Racer

Joined: Jan 2007

Posts: 308

Likes: 18

From: Sweden

Ok thanks.

Removed one of the old ones and they are AC R45S
Will the extended tip do any difference?
If not then why not use R44S and get the correct heat range?

/Johan

Edit: Or is R44S also out of production? Thought that was just R44...?

Last edited by Johan74; Feb 28, 2011 at 12:45 PM.

Mar 1, 2011 | 09:29 AM

laktrash

Heel & Toe

Joined: Feb 2002

Posts: 21

Likes: 0

From: friendsville tn

Where do champion plugs fall into the mix ? I also have a 69 350 with some slight mods. I use to use champion back in the day I did waste some $ splitfire along the won't go back there.

Mar 1, 2011 | 01:13 PM

Roughrider

Melting Slicks

Joined: Mar 2007

Posts: 2,100

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From: Frederick Maryland

Quote:

Originally Posted by laktrash

Where do champion plugs fall into the mix ? I also have a 69 350 with some slight mods. I use to use champion back in the day I did waste some $ splitfire along the won't go back there.

I wasted money on Splitfires...nothing but hyped crap. Replaced them with Champions and got good service. Champs, AC and Autolite have always worked well for me over the years, plus a private label made by Prestolite.

I do have to admit an awful lot of car guys and techs I know swear by NGK.