Weiand blower on a 330hp
 

Wanted to get it open and pinion on this, I have a formula 242 LS with a stock but fresh 330 HP. The engine has about 50 hours on it but it is stock with a basic ring and bearing job done to it. I was thinking about throwing a little Weiand 177 and a set of big valve #049's on and just doing a top end Basically, my question is how do you think the stock bottom end will do ? First off I'm not looking to go 60 or 70 MPH but dammit it would sure be nice to go at least 50 ! The boat right now maxed out is high 40s with a 21 pitch prop. My main goal is to achieve a cruising speed of about 40 don't really care how fast it is ! Yes, Maybe or Ka-Blam-O ? What's your guys thoughts !?

it has been done before.keep boost below 4 lbs and a safe tuneup and you will be ok,but don,t look for tons of power.

Thanks Mike, it should make about 400 wouldn't ya think ?

1st off what is wrong with the boat/setup? it should be faster than that. what rpm are you maxing out at? have you tried a 23? how bad is your current prop?? And you can pull 400 hp without the blower easily unless you want the blower bling and whine

400 to 425 is my guess.

I don't know if there's anything wrong with the boat phrahle, it has a 21 pitch stainless mirage 3 blade on it now but struggles to get on plane, but once on plane 4500-4600 rpm's at about 48 mile an hour on GPS, I put a 19 pitch three blade on it but the motor over revved at 5000 RPM and still only went 45 on GPS, so on to prop three, a 22 pitch four blade got on plane nicely but only revved the motor to about 4000-4200 rpm at about 45 mph on GPS, it did cruise nicely though, about 40 at 3000-3200 rpm's. It is my first boat and I'm learning more and more every time I'm out with it, just to me seems like it needs more power !

400-425 would be great to me mike exactly what I was thinking !

What rpm is your engine reving to now with the 21" in high 40's ? I've been many (other type) boats with 21's that run 50's and into 60's. Just wandering if your rpm is too low now.

4500-4600 SB, are them boats running 330's ?

using Bam's speed calculator with a 225 constant and a very conservative 5000 lb guess at you weight it shows 58 mph...even with slip you should be llow mid 50's. Do you have bottom paint? trimming correctly?? prop in good condition??

I just noticed you said it was your first boat, are you trimming it?? If your running with the bow stuck, that will be like driving with the brakes on,