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Discussion Starter #1
Guess my HP
Just had the new motor on the dyno for break in/tune/pulls before it gets dropped into my 65. Motor is all new from Butler.
69 400 block with a 4.25" stroker kit to get 461 cu in.
10.5/1 compression
Edelbrock round port heads cnc flowed to 330+ cfm.
Lunati hydraulic roller cam with .625 lift at the valves and .254 duration at .050 lift.
Performer RPM manifold with Pro Systems 850 custom carb.
Dougs 1 7/8" full length round port headers.
All logos and names milled off and evertything painted 65 Pontiac blue. Looks bone stock for a quick peek under the hood lol.
any guesses for HP and TQ?

Old post but finally got the motor dynoed. I'd put up the video if I could but everytime I try and upload i get an error message. Really frustrating!!!
 

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Wow, real close. Motor made 550 hp at 5500 and 590 tq at 4400. Motor was built with low rpm streetability as a must as its going in front of a tremec double ovcerdrive 6 speed. Heads would have supported a much more aggressive cam/intake/carb set up but I wasnt interested in high rpm numbers and a motor that wouldn't cruise. It made over 500 hp from 4400 to 6100 so its got a pretty flat curve, not peaky.
 

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Sounds like a beast of an engine for what i assume is a street car. Nice work. BTW i took my guesses from Jim Hands book on "How to build max performance Pontiac V-8"s" he has a dyno graph of a 473ci, 10:1 comp, 255cfm, witha Comp Cams XE294. I know your heads flow 330cfm so that had me thinking I'd be a little off but hey, pretty close. Can i ask what price range Butler is selling these for? Last I checked with Tin Indian a few years back they wanted upwards of $10K for a performance 455 build with 500hp, 550ft-lb with me supplying the 455.
 

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Nice! Love me some stroker motors.... A very timely post too, because I'm in the process of putting mine back together and right now am thinking about cams. I'm going "more" than what I had, but I've not yet decided how much more. Seeing that you're running with 254 @ 0.050 on a hydraulic roller and it still has good street manners is encouraging. I'll be going with a solid roller and have been playing around with simulations using Engine Analyzer Plus, getting similar numbers to what yours dyno'ed with similar cam profiles.

Bear
 
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