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Old 09-25-2011, 06:11 PM
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I am by no means a motor guy so maybe yall can help me out.

what can be done to a motor that has 10-1 compression to get more power?

can forced induction be used.

basicly i want to get more power but dont want to have to buy bigger motors.

any input would be appreciated.
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Old 09-25-2011, 06:40 PM
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Can't add boost with that compression.
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Old 09-25-2011, 07:30 PM
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thats what i thought
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Old 09-25-2011, 07:31 PM
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....Unless you add methanol injection.
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Old 09-25-2011, 09:01 PM
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or lower compression to around 8 to1
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Old 09-25-2011, 09:31 PM
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Better heads/intake would seem to be the likely option.
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Old 09-25-2011, 09:52 PM
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Quote:
Originally Posted by C_Spray View Post
Better heads/intake would seem to be the likely option.
yep also cam, carb drive height all adds up to speed I got 8mph gps by a 2'' shortie and carb change prop was small at that point but Iwent in for surgery came out drive carb steering msd boxes all gone and more Ithink there was another 2 or 3 mph left.
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Old 09-26-2011, 01:03 AM
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I have added a Whipple to 10:1 engines on several occasions. I actually build my 750's with the same bottom end as my larger, supercharged engines for that reason. You note only have to limit the amount of boost, but you have to have a really spot on tune. Obviously, I assume you have aluminum heads. The exact amount of boost will be largely determined by the camshaft. It's going to depend on cylinder pressures. As a general rule of thumb, you should be able to get away with 3-4 psi. I have squeezed out as much as 6 psi. You could always run a little more boost with some higher octane fuel added. You could add say 30-40 gals. of 110 octane to a 100 gallon tank, for example.
You have to be really careful on a carb engine without any form of knock protection. It can be done but the exact amount of boost will be determined by the rest of the combo. Let me know if I can help.
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Old 09-26-2011, 08:13 AM
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I agree, you can add FI on an engine like that if you have aluminum heads, keep it fat, run relatively low boost, and spray meth. Forged pistons would be a must. Race fuel would work as well, but it isn't feasible for most people to run daily. Ideally you'd want to lower the compression though...
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Old 09-26-2011, 09:42 AM
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Look up magnum machine in phone book. Call and ask for Curt. H has done lots and lots of performance marine engines in the area.
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