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Posted by: trekkor Jul 15 2004, 06:45 PM

I have a 1984 Corvette 350 with 4bbl and Edlebrock intake in my boat. Runs great and cool all day long.

What do you think is a safe max operating speed and a red line rpm?

Thanks guys.

KT

Posted by: trekkor Jul 15 2004, 06:55 PM

Everybody loves the pics


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Posted by: nebreitling Jul 15 2004, 07:12 PM

that'd be fast in a 914.

Posted by: smrz914 Jul 15 2004, 07:24 PM

I would say to be safe 5500rpm if it's a stock motor.

If it's ballanced then 6500rpm should be fine.

Not exaclty sure but this is where i would be if it were mine.

Posted by: bondo Jul 15 2004, 07:33 PM

Shouldn't the prop size and pitch be chosen such that WOT puts you at your peak HP? Assuming you keep the boat in the water (no James Bond type stuff) it would then be impossible to overrev the motor, and you should get the best top speed possible. (I could be wrong about this, it's just what makes sense to me... I'm no boat expert)

Posted by: trekkor Jul 15 2004, 10:53 PM

True about prop pitch. I'm 15x21 and 4400 rpm WOT.
4400 rpm is the right speed for the stock 305 Volvo Penta with a 2BBL @ 200hp.

I expect I have 300hp easy.

KT

Posted by: ablose58 Jul 16 2004, 03:29 AM

If I were you see what kind of rpms with current prop and then prop up from there. rule of thumb 1 up in prop pitch=200-300 rpm drop. Hope this helps you?

Posted by: SLITS Jul 16 2004, 01:35 PM

I run a blueprinted jet behind a pumped up 454 - 5500 RPM is the limit for me.

Posted by: jkeyzer Jul 16 2004, 02:03 PM

You mean V8s make power above 5000 rpm?

Posted by: SLITS Jul 16 2004, 07:02 PM

Off Peak power - still enough to pull the impeller thru the water - as the cam could feasibly go to 6500.

Posted by: TimT Jul 16 2004, 07:45 PM

Yeap... our old Chrisovich had twin crusaders I used to see about 5400 WOT

that made about 35 Knots... fast for a big ole wood boat

Posted by: DuckRyder Jul 17 2004, 07:08 AM

I'd prop it to turn around 5000-5200 at wot.

I wouldn't make a habit of running it around firewalled all the time though.

4400-4500 is probably a good everyday limit.

Posted by: dan10101 Jul 17 2004, 06:51 PM

So,,, Where's the picture of the boat!

I had a 283 in my wooden flatbottom. It would go to about 5500. (60mph or so).

Should be safe for 6000 or so with stock valve train.

Ok, the kettles' black. I can't find a pict of my boat anywhere. But, it was pre-digital age...

Posted by: trekkor Jul 17 2004, 09:05 PM

If all goes well. The boat will be on the water tomorrow afternoon. I'll get some shots for y'all.

20' deep v-hull cabin cruiser w/ bimini top, trim tabs, Volvo 280 drive. It'll do 35 mph. Fun boat. Weighs about 4000#.
'77 fiberform.

Posted by: trekkor Jul 18 2004, 09:35 PM

here's something.


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Posted by: trekkor Jul 18 2004, 09:42 PM

Had it on the Napa river for about an hour.
Revved it up to 5000 rpm's for short intervals and criused at 4400rpm's.

Got up to 38mph, fastest ever!

Cruises at 30-32 mph.

Notice the Corvette badge above the tow hook?


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