HP Limit for Stock 496 Cast Aluminum Piston?
08-28-2007, 02:48 PM
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Thanks Ray. I appreciate your input.
Actually the 550 hp at 5400 rpm is not documented by dynamometer test but indicative of the Innovation Marine GM HP3 Gen II motor I am emulating. The Innovation Marine GM HP3 Gen I motor is the motor you are refering to that produced ~515 hp at 5400 rpm and was campained in the Super V Light Class. I do plan on having Bob Lloyd dynamometer test my current motor when it is completed. Final ECU reprograming in process.
The iron heads and exhaust are not stock. The iron heads are the GM HP3 units you refered to (actually from that early 2000 build) that have received additional porting work c/o J. Valanko. The exhaust is the Dana EX2000 496 Flow Torque Exhaust which I believe you tested for Dana. In addition the cylinders have been bore notched to relieve the bore overhang of which you speak, unshroud the valves, improve flow and reduce hot spots and therefore potential for detonation. The pistons for the Innovation Marine GM HP3 Gen I and Gen II motors are totaly stock units is my information. The latest Innovation Marine GM 496 HPI motor that they are campaining however is a totally upgraded unit that uses forged pistons, 93 octane and produces 575 hp at 5600 rpm. By the way all of these hp ratings are with CMI exhaust dyno headers.
I have 90 hours on the stock 496HO. I have an additional 90 hours from last season on the emulated Innovation Marine GM HP3 Gen I motor ~490 hp (actual dyno) at 5400 rpm with stock Merc exhaust and stock HP3 heads. I have an additional 40 hours so far this season on the emulated Innovation Marine GM HP3 Gen II motor with Dana exhaust as described above.
I am a boat owner and not an engine builder.
Thanks again for all your input and information.
Actually the 550 hp at 5400 rpm is not documented by dynamometer test but indicative of the Innovation Marine GM HP3 Gen II motor I am emulating. The Innovation Marine GM HP3 Gen I motor is the motor you are refering to that produced ~515 hp at 5400 rpm and was campained in the Super V Light Class. I do plan on having Bob Lloyd dynamometer test my current motor when it is completed. Final ECU reprograming in process.
The iron heads and exhaust are not stock. The iron heads are the GM HP3 units you refered to (actually from that early 2000 build) that have received additional porting work c/o J. Valanko. The exhaust is the Dana EX2000 496 Flow Torque Exhaust which I believe you tested for Dana. In addition the cylinders have been bore notched to relieve the bore overhang of which you speak, unshroud the valves, improve flow and reduce hot spots and therefore potential for detonation. The pistons for the Innovation Marine GM HP3 Gen I and Gen II motors are totaly stock units is my information. The latest Innovation Marine GM 496 HPI motor that they are campaining however is a totally upgraded unit that uses forged pistons, 93 octane and produces 575 hp at 5600 rpm. By the way all of these hp ratings are with CMI exhaust dyno headers.
I have 90 hours on the stock 496HO. I have an additional 90 hours from last season on the emulated Innovation Marine GM HP3 Gen I motor ~490 hp (actual dyno) at 5400 rpm with stock Merc exhaust and stock HP3 heads. I have an additional 40 hours so far this season on the emulated Innovation Marine GM HP3 Gen II motor with Dana exhaust as described above.
I am a boat owner and not an engine builder.
Thanks again for all your input and information.
