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SRU1436 · 10-07-2022, 12:26 AM

Here is my recommendation, which I just did on my 66 chevelle. It had a sbc 350, a 7 blade fan and the Hayden 2705 fan clutch. I installed vintage air on the car and that fan clutch, 2705, wasn’t moving enough air to cool the engine while the AC was on. 195 (AC Off) and it would get to 215 and climb until I turned the AC off if the air temp outside was around 95-100 (I live in California so it gets hot, not as hot as AZ). I switched to the 2747 HD fan clutch and it now keeps the engine within a normal range 180 (AC Off) and 195-200 (AC on).

I don’t hear a difference in the fan noise.

2705 Hayden fan clutch stats : Turns the fan 50-60% of shaft speed when engaged (Per Hayden)

2747 Hayden fan clutch stats: Turns the fan 80-90% of shaft speed when engaged (Per Hayden)

I hope this helps.

10-07-2022, 12:26 AM	#10
SRU1436 Registered User Join Date: Mar 2019 Location: Northern California Posts: 211	Re: Clutch Fan and fan combo doesn't fit Here is my recommendation, which I just did on my 66 chevelle. It had a sbc 350, a 7 blade fan and the Hayden 2705 fan clutch. I installed vintage air on the car and that fan clutch, 2705, wasn’t moving enough air to cool the engine while the AC was on. 195 (AC Off) and it would get to 215 and climb until I turned the AC off if the air temp outside was around 95-100 (I live in California so it gets hot, not as hot as AZ). I switched to the 2747 HD fan clutch and it now keeps the engine within a normal range 180 (AC Off) and 195-200 (AC on). I don’t hear a difference in the fan noise. 2705 Hayden fan clutch stats : Turns the fan 50-60% of shaft speed when engaged (Per Hayden) 2747 Hayden fan clutch stats: Turns the fan 80-90% of shaft speed when engaged (Per Hayden) I hope this helps.