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Gaining more horsepower from a 496 mercruiser 8.1

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Gaining more horsepower from a 496 mercruiser 8.1

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Old 10-11-2012, 09:13 PM
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Default Gaining more horsepower from a 496 mercruiser 8.1

Is it possible to build a 496 mercruiser motor like you would build a 502. I know you can take a 502 and build it to a 540 bulldog. Is it possible to do it to a 496? They are totally different blocks. correct? or is it just the bore is different. Can they use some of the same parts that are used in a 540.

What would it take to increase the horsepower. Are they reasonable priced kits. Is it worth it or does it take away from reliablity

Thanks
David
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Old 10-11-2012, 09:33 PM
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whipple, raylar, there are plenty of options
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Old 10-11-2012, 10:10 PM
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it is nearly a 1/4 inch of bore. takes a completely different block (wall thickness) to get that bore. the biggest difference is the breathing room under the valves the bigger bore allows. you can get a lot of power out of a 496. most of the components from a 502 will fit a 496, but the smaller bore will not allow for the airflow needed for serious power. the price of fuel you are gonna be burning, spend the dinero for a 502 block. or a 540 or a 572...
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Old 10-11-2012, 10:43 PM
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502 is generation 5 or 6 (depends) & 496(8.1) are generation 7 and are different.

DART makes heads and blocks for the 8.1/496

Raylar makes a 496/8.1 kit for 525 HP or 600 HP. They had stroker cranks at one time but you would have to inquire. He makes a very nice aluminum head for the 8.1/496. Nice product and priced fair for the level of products you get.

I havent run my boat in 5 months and started it today. The Raylar 600's started in about 2-3 seconds. To be honest, I forgot how good they actually sounded.
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Old 10-12-2012, 01:42 AM
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Dart Gen VII stuff and they even have an intake manifold for a swap over to a carb set up if U want to get rid of the MPI setup. They have blocks and heads also for this app. plus as above mentions of others. Is Raylar still around currently ? Just asking

Last edited by BUP; 10-12-2012 at 01:45 AM.
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