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-   -   502 ci on 89 octane build (https://www.offshoreonly.com/forums/general-boating-discussion/325627-502-ci-89-octane-build.html)

louisfever 04-27-2015 12:23 PM

502 ci on 89 octane build
 
Is it possible to build a 502 with 9.0 compression ratio so it would run on 89 octane and make 600 HP ?????
Whats the best parts to use........
heads ???????
cam ?????
Carb ????
Intake ????
Ignition ?......

fastdonzi 04-27-2015 01:59 PM

I believe with Aluminum heads you can run a higher comp ratio. I'm not a engine builder but I know a guy...Lol

Rattlesnake Jake 04-27-2015 02:39 PM

I did a 500 EFI with AFRs, 9.5 JEs .030 over,Bob Madara Cam & lifters, etc. Jason Saris did the final assembly, dynoed and programed it to run on 89 octane. Made 572 HP @ 5400, 606 tq @ 4500.

Tinkerer 04-27-2015 08:05 PM

I have two 509's with Dart Pro 1 alum heads that runs fine on 89 octane with 10.0 to 1 comp ratio. I do have the pistons zero decked for good quench. I am running the 741 hyd roller cam, Lightning headers and they produce 650 HP.

Rookie 04-27-2015 08:15 PM

I ran 89 octane. Dart Pro1 heads 9.7:1 454's 590HP 6500RPM's. Now 87 octane @ 9.0:1.
Locked timing 35*, Crane HI-6M.

SB 04-27-2015 09:37 PM


Originally Posted by louisfever (Post 4297403)
Is it possible to build a 502 with 9.0 compression ratio so it would run on 89 octane and make 600 HP ?????
Whats the best parts to use........
heads ???????
cam ?????
Carb ????
Intake ????
Ignition ?......

Yes.

BUP 04-27-2015 09:50 PM

Man you are funny tonite ^^^^

Its like motor and gear oil you will get so many opinions & replies about different apps and builds.. just saying

fastdonzi 04-28-2015 07:31 AM


Originally Posted by Tinkerer (Post 4297576)
. I do have the pistons zero decked for good quench. .

For any motor that isnt High Compression the Quench being right is Very important. Get it wrong and you got a Pig with a bunch of good parts..Get it right and you'll be smiling.. Read Up !!!!

Stormrider 04-28-2015 08:58 AM

515ci 8.7:1 compression
587hp @ 5700rpm
586lb-ft @ 5000rpm

Louie 04-28-2015 06:27 PM

I just ran yesterday. 509, 9-1, ported heads and intakes, Marine Kinetics cams, 235/239 640/655. DaVinci carbs. Made 597hp at 5700.


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