Motor experts, need help setting up

**scmoose** · 09-20-2013, 02:01 PM

Originally Posted by willyworm

Dan forwarded me to the guys at Powertech and he's sending me a SCB12 pitch semi cleaver. Said it would help my boat run a little flatter like it should, adn get my RPMs right.

I hope it works out cause as much as I'd love to spend the money for the that 70, I'm trying to avoid it. But if this boat doesn't hit 30mph+ with this new prop, it just may force my hand.

Keep us posted on how this prop works out, thats the one Im leaning towards myself.

**Buckin Bronco** · 09-20-2013, 12:14 PM

Get the 70. Trust me.

**B.Miller** · 09-20-2013, 12:34 PM

Trust from my experience, once you hit 30 you'll want 35, then 40, etc. Go with the 70 that way you don't have to tear into the engine to get power. Plus a big block purrs so nice.

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**willyworm** · 09-20-2013, 01:42 PM

Like I told Phone Man.... you guys talk like money grew on trees.

**B.Miller** · 09-20-2013, 02:33 PM

Originally Posted by willyworm

Like I told Phone Man.... you guys talk like money grew on trees.

Bro I got a money and ticket tree! You wanna go see Luke Bryan with me? ;-)

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**willyworm** · 09-20-2013, 01:44 PM

Hell I can't remember how many years I had to save up to pay cash for the damn hull, USED.

I don't finance anything, except the house.

Rubberhead* · 09-23-2013, 01:23 PM

Originally Posted by willyworm

I don't finance anything, except the house.

Smart man. :clap:

**Phone Man** · 09-20-2013, 01:52 PM

Way i look at it is, you aint promised tommorow. If you want something and can swing it, buy it. Many people skrimp and save for retirement only to not be physically able. I want to enjoy things while i can. Point in reference of my prodrive. Its on the way to hzve it gone through and put reliable parts in it. Ive said screw briggs warranty. Im wasting time not getting to use my boat waiting on them to decide how to fix it. Just my philosophy for today

**willyworm** · 09-20-2013, 08:23 PM

Got a ticket oak huh?

Does a fat kid love cake? Hell yeah I'd go to a LB gig.

You know how much poontang is at one of his shows?

**B.Miller** · 10-23-2013, 07:05 AM

Originally Posted by willyworm

Got a ticket oak huh?

Does a fat kid love cake? Hell yeah I'd go to a LB gig.

You know how much poontang is at one of his shows?

Oh and confirmed, tail was errrywhere!

**willyworm** · 09-20-2013, 08:31 PM

PM, I can't argue with ya on that mindset, and I completely agree. I could afford to buy that motor cash, but I can't justify spending it until the employment situation becomes a little more solid. Plus the Nissan works fine. It'll work finer when I get that prop in.

Rubberhead* · 09-23-2013, 01:28 PM

Originally Posted by willyworm

It'll work finer when I get that prop in.

Let us know once you run that new 12" prop. I'd hate to miss a chance to quote myself...

**Phone Man** · 09-20-2013, 08:36 PM

I hope it does Willy. I'm ready to see the xpress on the water again.

**willyworm** · 09-20-2013, 11:23 PM

And I'm ready to get it on the water again. Probably won't be much this year though. Not til I get this damn degree finished up.

**willyworm** · 09-23-2013, 09:52 PM

Hehe. I'll see if I can help create the opportunity. Gotta ship this other one back tomorrow, hopefully the new one will be in by the weekend.

**willyworm** · 09-26-2013, 07:20 PM

So I took her out for another run today with the new 12p Powertech. It got on plane quick but still had issues with speed. Only 26 mph trimmed out as far as I could before the front end started to bounce. Tiny tach still reading in the lower 4000's in the rpm range.

There is obviously some other problems going on. Could be one or a combination of problems. They include: my tiny tach ain't set up right as far as sparks per revolution etc, it's getting interference from somewhere, the motor height needs to change, prop pitch needs to change, or my motor either is not getting to full WOT doe snot have as of a compression as it should.

I did notice that with the motor not running I turned the throttle wide open, and my top carb was wide open while lower two carbs were not, so I adjusted the small bar that connects the three to where they were all in sync. Some other adjustments were needed so I tinkered and finally got frustrated and had to leaver the river to go pick up kids.

I'll calm down and pick it up again, but I'm getting frustrated with it. Still want to check compression, but I suspect that is not the issue as the motor runs pretty strong. Two things I can't figure out is the speed and the rpm's.

**carolinaboy06** · 09-30-2013, 11:20 AM

Originally Posted by willyworm

I'll calm down and pick it up again, but I'm getting frustrated with it. Still want to check compression, but I suspect that is not the issue as the motor runs pretty strong. Two things I can't figure out is the speed and the rpm's.

I'd do a compression test before I did anything else just to rule it out. Compression directly relates to speed and RPM's.

Rubberhead* · 09-30-2013, 12:33 PM

Okay, not accounting for slip your speed in miles per hour = RPM x pitch / gear ratio / 1056.

For you that is 4200 x 12 / 1.85 / 1056 = 25.8 MPH.

Your tach sounds right.

If you can get 5,500 RPMs, then you should be going 33.8 MPH.

Either your boat is way too heavy for the 40hp or your motor isn't giving you 40hp...

**B.Miller** · 09-30-2013, 12:35 PM

Originally Posted by Rubberhead*

Okay, not accounting for slip your speed in miles per hour = RPM x pitch / gear ratio / 1056.

For you that is 4200 x 12 / 1.85 / 1056 = 25.8 MPH.

Your tach sounds right.

If you can get 5,500 RPMs, then you should be going 33.8 MPH.

Either your boat is way too heavy for the 40hp or your motor isn't giving you 40hp...

My guess. From driving Buckin Bronco's with the 50, it's a heavy effin boat!