327 HP question
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Pro
Joined: Jun 2011
Posts: 588
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From: Ohio
327 HP question
I have a NOM 327 300 HP in my 63. However it has the large 21/2 inch exhaust manifold with all 2 1/2 ehaust all the way back. It also has an aluminum 340 hp intake. Question...how much HP with these two additions add to this 300 hp setup? Is it closer to 340 now or still closer to 300?
thanks
thanks
Race Director
Joined: Oct 2000
Posts: 12,687
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From: Shamong, NJ
Only the 327/250 and the Powerglide 300 hp, used the 2" manifolds and pipes.Without some internal modifications, the addition of just the aluminum intake, would have little or no effect on the engine's horsepower.
Safety Car
Joined: Feb 1999
Posts: 3,631
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From: Fountain Hills AZ
The cr was the same for both engines, as was the cam. The 300 had better heads and a larger carb. If manual, it got the 2.5" manifolds and exhaust. IMO opinion the heads provided the largest improvement, followed by the carb. I don't think there was a 50 hp difference between the two engines. The difference had more to do with the marketing guys.
Race Director
Joined: Oct 2005
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From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
Hey, wait a minute.
According to my 1973 JC Whitney catalog, a chrome air cleaner was worth 10 HP, finned cast alum valve covers were worth 10 HP, Cherry bomb mufflers were worth at least 20 HP, bigger exhaust pipes were worth 20-30 HP, headers were worth 100 HP, that 3/4 race cam was worth at least 100 HP. The flexible fan was good for 10-15 HP, the finned oil pan was good for 10 HP.
Leaving out the cam change, just a bunch of bolt on parts get you almost 200 HP more than stock.
Doug
According to my 1973 JC Whitney catalog, a chrome air cleaner was worth 10 HP, finned cast alum valve covers were worth 10 HP, Cherry bomb mufflers were worth at least 20 HP, bigger exhaust pipes were worth 20-30 HP, headers were worth 100 HP, that 3/4 race cam was worth at least 100 HP. The flexible fan was good for 10-15 HP, the finned oil pan was good for 10 HP.
Leaving out the cam change, just a bunch of bolt on parts get you almost 200 HP more than stock.
Doug
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Melting Slicks
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From: DFW
Since it's an NOM, I'd want to know more about what's inside. Barring that, it's at least helpfully to know when it runs out of air... Namely when does start to go flat and beg to be shifted? Lower power (300 HP) will be around 5000. Higher HP will be 5500 to 6500.
Harry
Harry