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-   -   opinion 383vs454 (https://www.offshoreonly.com/forums/general-q/259809-opinion-383vs454.html)

87MagnumII 08-09-2011 06:49 PM


Originally Posted by GPM (Post 3474281)
That might take a lot of HP.

I second that motion

JeremyAnderson 08-09-2011 08:28 PM

350 to 383 is night and day, but it will take a BBC with a blower to gain 25mph! I really think you'll like the 383

prerunner404 08-11-2011 11:58 AM

ok i was afraid of that i was gonna have to go big block to get some mph outta her what kind of speed increase do you think ill get with the 383?

tmdog 08-11-2011 05:09 PM

Build a 383 right and that boat of yours will do hi 60's or 70.
Dump the tbi and carb it.
Dynoed my 383 at 491h/498t. Boat equipped w/ Alpha.

prerunner404 08-12-2011 02:40 PM

how long you been pushing it with that alpha tmdog? how big is your boat

prerunner404 08-12-2011 04:41 PM

also what prop sizes are you guys running on your alphas with the 383

Fenderjack 08-12-2011 04:49 PM

What gearing is the alpha??


John

GPM 08-12-2011 05:03 PM

What HP are you running now ?

onesickpantera 08-12-2011 05:25 PM


Originally Posted by prerunner404 (Post 3474233)
well im sold then ill do the 383 it seem to make more sense to me. right now my boat only runs about 35-40 with the 350 i have it has about 350 hrs on it so i know she is gettin tired i have to run it at wot(4500rpm or so) just to get any where and that yeilds me about 35 mph. im looking to get the boat to run in mid50's to low 60's. im always easy on outta the hole take offs so i think i can baby the drive for a few seasons.

its a tbi motor so can i reuse the tbi? or do i have to switch over to carb or multi port injection?

That seems like VERY low mph. Unless that motor is hurt I agree you are going to need A LOT of hp to hit 60mph.

Are you running an aluminum prop?

tmdog 08-12-2011 06:15 PM


Originally Posted by prerunner404 (Post 3477300)
how long you been pushing it with that alpha tmdog? how big is your boat

383 is mounted on a 18 Donzi and been running 400+hp for the past 4yrs. Alpha has a 1.5 gear and turning a 25 Hydro.
Building a solid and reliable eng. is critical and very costly. Did I mention costly.


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