327 RPM range

[sodly]

Can anyone tell me the stock red line for a stock 1966 C20 with a 327 and TH400? Where does one put the red marker on the tach? How does the auto's shift points play into this red line? Or do they?

[Rich 5150 69]

Factory ratings for the high torque 327 with Th-400, 220 HP at 4400 RPM max torque at 320 FT lbs at 2800 RPM, so limit your Redline to 4500 rpm. Thats with a 4-barrel carb, 8.5 compression.

[Trsmotrhed]

I always thought a 327 liked to rev. So my 327 I had in my camaro didn't like 6,000 to 6,250 for shifting? Sure seemed like it loved to rev. I would think for a stock 327 in your truck 5,000 to 5,500 would be no problem if you was needing a little extra go power.

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[sodly]

I wonder how the tachs came set from the factory? Surely there must've been a "correct" number.

[60-66]

This first one is factory installed in our 66 K20 with 292.



This one not sure if its been played with but its in our 64 K10 283


Like to see a 66 327 Tach that's not been out of the cluster ?

[Rich 5150 69]

Originally Posted by Trsmotrhed

I always thought a 327 liked to rev. So my 327 I had in my camaro didn't like 6,000 to 6,250 for shifting? Sure seemed like it loved to rev. I would think for a stock 327 in your truck 5,000 to 5,500 would be no problem if you was needing a little extra go power.

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We are talking truck motors here, they were built with more torque and low end power for hauling/towing not high winding horsepower they used small valves, and low compression to achieve this, 220 horse max, anything else was fair game, bigger valves better, flowing heads, larger cams and more compression....

[sodly]

Would it be safe to assume that a 327 would have a slightly higher red line than a 283?

Also, I presume the lower red arrow is the bottom of the "power band" or the "working RPM range." In other words, don't work the motor too hard below this point. Of course with the TH400 I suppose all of this is rather moot.

[Rich 5150 69]

Virtually the same, the 327 had more torque in the lower rpm..!