'74 L82 with AC tach red line question
Thread Starter
Instructor
Joined: Nov 2012
Posts: 219
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From: Irma Northern WI
'74 L82 with AC tach red line question
I just picked up a '74 with an L82 and AC. It does not have a 6,000 rpm red line tach. I looked at an interchange manual and it does indicate that a car with AC uses a different tach than the a car without AC. The manual does not indicate the red line on either. I would like to know what the red line should show in my car. Thanks in advance.
Le Mans Master
Joined: Oct 2007
Posts: 7,429
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From: Tennessee/Rhode Island
My 78 L-82 4 speed with AC redlines with the L-82 tach at 5,600 and my friends 78 L-82 without AC, redlines at 6,000. GM didn't want the R4 compressor spinning that high with AC. There is no difference in the motors. I don't have the compressor in mine installed and have not for years-rev it to 6,000. Hope that helps!
Thread Starter
Instructor
Joined: Nov 2012
Posts: 219
Likes: 0
From: Irma Northern WI
My 78 L-82 4 speed with AC redlines with the L-82 tach at 5,600 and my friends 78 L-82 without AC, redlines at 6,000. GM didn't want the R4 compressor spinning that high with AC. There is no difference in the motors. I don't have the compressor in mine installed and have not for years-rev it to 6,000. Hope that helps!
