Offshoreonly.com - Scarab 377 speed and stuff

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Quote:

Originally Posted by hblair (Post 4879105)

Bill Lawson at ateco engines near chicago has a 377 raised deck scarb named dazzlement. Super cool old boat. Same style as yours. He may be a good person to talk to. He's had the boat a long time and is gonna try to get it back in the water for next season. Here's a picture of his boat. There was a monogram model sold with it's likeness back in the eighties.

I built that model! I totally forgot about it until I saw your post

Quote:

Originally Posted by getrdunn (Post 4879160)

I get it trust me BUT don’t forget my advice! I don’t listen to my own either so I should just shut the fk up! 😂

I won't forget it. I really like this boat and I would like to hold onto it for a while. I always wanted an old wave-crusher and was hoping to go 75-80. I know there will always be faster boats out there but I really like 80mph haha

Hahaha, right now you want 75-80 then it`s 80-85 then gotta get into the 90`s!
Its a disease and we all have it!

Quote:

Originally Posted by resurrected (Post 4879176)

Hahaha, right now you want 75-80 then it`s 80-85 then gotta get into the 90`s!
Its a disease and we all have it!

My friend has "The Preacher" 10 meter Fountain across from my slip, I'll just ride with him when I wanna go 100mph hahaha but yeah you're right.

Really nice clean 377. Great find.

177s as you know are pretty small for a 540. But it will probably get you over the hump of performance. The 177s have a peak rpm of about 15k, but that is totally maxed out.

Lots of good threads on here about 177s. They can push some air, and coupled with modern head and cam tech, they are better yet.

There is a limit where the heat generated by the blower at the limit, will super heat the air to the density where it would be the same NA or worse off. You still have the parasitic losses.

When the blower cases get heat soaked...they will open up the clearances...making them less efficient. So a dyno pull is not the same as a sustained run at close to or WOT.

Reading the B&M Magazine data book from 1990, they really did a good job of dialing in their 420s with the twin rotor using teflon strips and good rotor design. The twin opened up some volume compared to the triple screw roots, why they are considered a 7-71.

Some prop changes can make a world of difference. Bblades can help with that.

Weiand 177 max rpm is 13500. I spun mine to about 12500rpms on my 525SC.
If you're spinning it 10k+, its best to change the lube every 20 hrs.

Quote:

Originally Posted by Franks292 (Post 4879031)

I also have a set of 26 pitch 4 blades to try. Was curious what everyone else's thoughts were. Any advice is appreciated! Thanks everyone!

Glad to see you were finally able to get your boat in the water. I would try those 26" 4-blades as long as you have them. They just might raise your RPM's a little more if the engines actually make peak power @5700rpm---not saying they will get you to 5700rpm, but maybe more than the 5000rpm with the 3-bladed props you already have and see what happens.

I mean, you might as well try those 4-blade 26's----so put them on, give it a whirl and let'r buck