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Thanks to G Kull who ran a desktop dyno and gave me some hp numbers for my 327. Peak hp of 398@6000 and peak torque of 375@5000. For the money I got in the thing I was hoping for alot better than that. :confused: For half the price I could've had a crate motor with that :mad . Any suggestions as to what to do to bump the hp up a little, say 450-475? Thanks Classic
Those are some pretty stout numbers for a 327. You are getting 1.2HP per cubic inch. The solution to getting more power, my friend, is more cubes or a power adder. I feel your pain. When I had my 327 rebuilt I should have gotten a 406 instead. Consider if you had a 406 with the same power per cubic inch, you would have 494HP. Of course, to keep your specific output up with more displacement you may need better heads, exhaust, and intake. Or you could use a lot of the parts you have and probably get 450HP. Gotta do some serious calculating before assembly to meet specific goals.
One thing you can do to get more power from the 327 is put in a bigger cam and raise the peak power RPM. Of course this will make it more of a pain to drive on the street. Another thing would be nitrous, of course. That's probably the cheapest way to blow right past your goal number from where you are now.
Notice how you have lots of good pieces and are not getting much more than the rated power these engines had in the '60's? It certainly looks like Chevy over-rated the 327's. People have told me that stock L79's like mine (327/350HP, hydraulic cam) would pull only about 280-300 on a dyno back in the day.
L79, I do have a 150 hp nitrous on it already, but I don't want to factor that in. I was looking for 450-475 n/a instead of 400. Two reasons made me think this was possible. 1. The '65 327 was rated at 375, the highest I know of. I figured 37 years of technology would be worth something along with the fact that I wasn't going to be making a mass produced engine that had to live up to a warranty. 2. Edelbrock states that 420 hp was made with their power-pak on a 350. I went with the power-pak, but went with a bigger cam than specified, along with the air gap. I didn't realize that a 327 would take that much of a hit from a 350. 23 measly cubic inches. I am not a mechanic, so I don't know what I could have done differently. Classic
Something else may be wrong then in the simulation. With an even bigger cam than the RPM cam, you should be making peak power above 6000RPM.
With the right exhaust, and assuming you still have the forged crank, you should be able to put in a cam that peaks at 6500 or even 6700, and rev to 7000. This would require a solid lifter setup.
Are you driving this on the street though? If so, you probably already have about as wild a cam as you really want on a 327.
The best online small-block expert I've found hangs out at http://www.chevytalk.com . Go to the "performance related" forum and post your numbers there and ask for advice on improving them.
You need a forged bottom end, some AFR 195 heads, a Victor Jr. intake, Demon 750 carb, or Holley 950 Pro-Jection, a big Solid Lifter cam, 11.5:1 compression, and a good ignition system.
You'll have no torque below 3000, but you should be able to make the kind of power you're looking for if you spin it to 7 or 7.5 K RPMs.
The '64 and '65 375 horse cars had 11:1 compression, ran leaded gas, solid lifter camshafts, fuelie 2.02 heads, and mechanical fuel injection. Also the HP rating was gross horse power which is measured with absoutely no loads on the engine.
Sounds to me like you have a good running 327 as it is. The mods I said won't make it very streetable at all. :seeya