SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: Handi-Crack on August 30, 2014, 12:00:57 PM

Title: Offy vs torker
Post by: Handi-Crack on August 30, 2014, 12:00:57 PM
Another subject I've been reading up on and wouldn't mind some input from the jet side.
Title: Re: Offy vs torker
Post by: GlassCutter on August 30, 2014, 12:13:49 PM
Most people will be happiest with a single plane manifold design regardless of mfg.

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Title: Re: Offy vs torker
Post by: Squirrel Master on August 30, 2014, 12:26:17 PM
Glasscutter i thaught  dual planes make help more torqur
Title: Re: Offy vs torker
Post by: GlassCutter on August 30, 2014, 12:30:06 PM
Low end torque is not real important in a jetboat.   How much time do you run at 2k vs. time you spend at 3,000 plus?

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Title: Re: Offy vs torker
Post by: Squirrel Master on August 30, 2014, 12:32:37 PM
Well I haven't got mine on the water yet so I don't run lol but I see your point so if I made 470 horse what manifold would squeeze more out a 460

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Title: Re: Offy vs torker
Post by: Handi-Crack on August 30, 2014, 12:38:25 PM
Yeah now I'm even more confused, I have a torker intake but from what I hear/read olds are low end motors. If the 455 doesn't like to run at high rpms wouldn't a dual plane intake give me more useable power since I'd be around 3-4k most of the time?
Title: Re: Offy vs torker
Post by: GlassCutter on August 30, 2014, 12:48:23 PM
3-4k isn't really "low end" when it takes 3k to stay on plane and 4800-5000 is your red line.  When you drive a jet it is generally going from zero to 35-50 mph before letting off.  No one drives a car like a boat.

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Title: Re: Offy vs torker
Post by: Handi-Crack on August 30, 2014, 12:56:52 PM
But aren't dual good for 1500-6000 on response and single kick in at higher up to 8-9?
Title: Re: Offy vs torker
Post by: GlassCutter on August 30, 2014, 01:15:45 PM
Cars and boats = Apples and oranges

Nothing you read about what works for cars applies to boats.  Well almost nothing.  You are pretty limited to working with a powerband between 3000 and 5000 rpm.  Nothing above 5,500 rpm matters.  The dyno in your ass is never going to notice whether you low end torque has changed a few foot pounds under 3,000 rpm.
Title: Re: Offy vs torker
Post by: Handi-Crack on August 30, 2014, 02:56:57 PM
Awesome I knew there was a difference just like to learn more thanks for the input
Title: Re: Offy vs torker
Post by: Flusher on September 02, 2014, 11:12:37 AM
Here is a good read if you really want to start understanding intake manifold science.
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