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650 HP naturally aspirated build ideas

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650 HP naturally aspirated build ideas

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Old 01-08-2019, 12:43 PM
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Default 650 HP naturally aspirated build ideas

Gentlemen

I am looking to build 650hp NA for my straight bottom 32' fever

The only parts I have Ordered and have are the following:
Engine quest 320 Heads (Bare)
Thunder and lightning exhaust from Diamond

Starting off with stock 502 engines
Please keep this civil, and I would like to try and achieve this goal with off the shelf components, No magic cams and heads that aren't readily available, no magic DYNO numbers, my goal is to keep this thread as truly informative and objectionable without any issues.

I plan on starting this project in 2 to 4 weeks......

SO GO
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Old 01-08-2019, 01:23 PM
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What I did was -
-Have the heads ported
-525 cams or similar
-Headers
-Holley intake and 2000 CFM throttle body

Close to 600 hp will run close to 100 on a 32 fever.
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Old 01-08-2019, 01:33 PM
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540 build that many have done currently and before.
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Old 01-08-2019, 02:50 PM
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Does anybody have specific information about a build and not general statements, better yet post a build sheet with parts used and dyno results..........looking for good information
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Old 01-08-2019, 04:35 PM
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I could post a build sheet, but I started with a 454, so I don't think it would help much. As an FYI, the block is 80 over, 4.25" crank, Molnar 6.385 forged H-beam rods, Diamond pistons, cam very similar to 525 cam, GM Aluminum heads ported/polished by CFE, 10:1 compression, dual plane alum intake, 850 carb, Stainless Marine exhaust that is dry to the tips. Ran 598 hp @ 6,000 and 585 torque at 4300. It was built by Automotive Machinery in Fraser, MI.

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Old 01-08-2019, 04:39 PM
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https://www.offshoreonly.com/forums/...ake-650hp.html

650HP 540ci combination conversations are plentiful around here. Search?
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Old 01-08-2019, 06:54 PM
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If you can't get 650 HP out of a 540 build than You should go back to school.
540 cubes, Hyd. roller cam, decent heads - Dart or AFR,
I was at 650 HP out of a 509 with those parts.
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Old 01-08-2019, 07:01 PM
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Pretty much a decent set of heads (AFR315cnc), 741 cam, ~10:1, and exhaust should get most any 502+ around 650hp, no?
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Old 01-08-2019, 08:54 PM
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Sounds like you are off to a good start! 650 is the perfect Target goal for best overall value vs reliability. Chasing more power N/A starts costing more money than forced induction with less reliability and fun driveability.

Your heads are a good choice.

Molnar technologies offers some good stuff for the money.

Going 522cu/in would be cool and might save you a few bucks on a crank. Obviously you can go bigger but this hobby is expensive enough lol! Would rather see money spent on a more reliable valve train if you had to choose.

What induction were you thinking? Can you give us more info on your engines that are starting from. Any parts you want to reuse or that can't be reused?
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Old 01-08-2019, 09:26 PM
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Gonna need pistons at minimum to get the compression up. Might as well bore to 4.500 and make them 509s. Id try to get as close to 10:1 as possible. Id upgrade rods as well, to a set of Molnar rods. By the time you rebuild the stock rods, it just makes more sense. The molnar, or even an eagle rod is a nice upgrade over the stockers.

dont be afraid to put some camshaft in it. A 32 fountain doesnt need dumptruck cams that make gobs of torque at 2000rpm and fall on their face at 5200.

The EQ head is easily capable of your power goal. A little cleanup work and a good valve job goes a long way on them.

Helped oso member cruel intentions with his builds. 502ci , 8.7:1 compression, stock eq heads, stock merlin intake, off the shelf 850 quick fuel. Cams were 242/250 112 LSA , .630 lift. Fully dressed with sea pump, circulating pump, alternator, etc, and wet marine exhaust, made 565hp if i recall. Bet my azz with no accessories and dry open dyno headers, it would have made 600 with ease. But, he was more concerned with a real number and real tune.

your setup, with say 10:1, a 950 ultra carb, should make some nice power. I wouldnt worry much about what others claim for power. Theres alot of optimistic dynos out there these days. Recently saw a sheet that claimed 850hp , yet was only using about 740hp worth of fuel
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