Fixed cooling fans for a 340

To everyone that keeps telling this guy the fan isn’t the problem and changing it won’t help, you guys are not correct. From what I learned 1.5 years ago when I went thru a similar question (7 blade fixed vs 6 blade clutch) my end result was to skip using the 6 blade and measure pitch… The new to me 6 blade was not a major improvement in pitch to the 1.5” pitch 7 blade (slant 6 fan). I looked in factory service manual and it said 340 cars were equipped with 7 blade 2.25” pitch, and I opted to go to a factory spec 7 blade fan (even though it was a cheaper GM 772 with same specs).

Kenflo has a performance engine and the 5 blade fans were not standard on performance engine options. Were they on 318s and 360s, yes, but those were not considered the performance engine option (360 guys might argue but they were detuned compared to a 340 back in the 70s). So the best course is to trust your gut and swap the fan to a 7 blade 2.25” pitch 18” fan. It’s also the least intrusive option, everything else is taking the engine apart…