Surface running props

**OnPad** · 05-22-2024, 01:05 AM

6500 - 7000rpm is where I'm running with 14.5 × 28p × 4 blades, 1.87 gears, and slightly modified 200xri, and150 supermag.This combo gives a decent hole shot, good midrange, and top speeds of 75, and 82mph.

I've been wanting to try a Mazco re4 after running a re3 the other day. I think that would be a wicked fast prop in 28, or 30p. The 28p re3 put a bunch of my choppers to shame, except it had my 7000rpm tach buried and took a second to come of the stop when I lifted.

**DangerNewb** · 05-22-2024, 05:09 AM

Originally Posted by OnPad

6500 - 7000rpm is where I'm running with 14.5 × 28p × 4 blades, 1.87 gears, and slightly modified 200xri, and150 supermag.This combo gives a decent hole shot, good midrange, and top speeds of 75, and 82mph.

I've been wanting to try a Mazco re4 after running a re3 the other day. I think that would be a wicked fast prop in 28, or 30p. The 28p re3 put a bunch of my choppers to shame, except it had my 7000rpm tach buried and took a second to come of the stop when I lifted.

I've got a very nice small shaft Mazco 28 re4 listed if interested.

**rjdubiel** · 05-22-2024, 07:13 AM

Originally Posted by skialot2

Yes I have metal cage rod bearings. All rod and main bearing are brand new. All the electronics came off a stock 98 150. Nothing special.

is that the 40 amp with the heavy flywheel? If it is stay under 7k, don't hold it all day at WOT. Now if its 16 amp with the lighter flywheel or even get a lightweight flywheel and you can turn it harder for WOT runs but still, don't go 15 miles WOT the whole way! trying to prop for 5600 or 6000 rpm is tough as you have to go so high on the pitch like you think but the take off will be horrible. Find the prop that gets you 6800-7K at max speed if you have 40 amp. if 16 amp see what it will turn WOT, maybe it will make it to 8K but I doubt it.

**Capt j** · 05-23-2024, 12:15 AM

Promax or the new Bravo OT I think it is.....the FS/XS are pretty good too.

**David** · 05-23-2024, 08:35 AM

Originally Posted by skialot2

Thanks everybody for the input. This really wasn't supposed to be about what pitch to run. Pitch kind of picks itself depending on the RPM's you want to run. The prop I am using now is a Quicksilver Chopper that was reworked by someone before I bought it from eBay. When I was using it on my Glastron with my 135 it ran 5500RPM's. (No LWP. 2 top holes plugged. Ran 3" below keel. No pad) It ran fine. But I noticed one blade had a couple minor bends on the face. I called Hill Marine to have it reconditioned. When I told Ron the prop was already probably labbed, he said you never know what someone else did to it. Then suggested I buy one of their Signature Choppers. So, I did. I ordered a 28P Chopper 3. It ran 400 RPM higher on 5 MPH slower. So I sent it back and exchanged it for a 30 Pitch. That 30P prop ran the same 5500 RPM, but still 2 MPH slower as the labbed 26 chopper. When I switched to my Checkmate with the 150, it ran 5600 with the Hill Chopper until I lost it when the mid section broke. When I fixed the 150. It ran 5600 with the Quicksilver Chopper. That is why I say this prop has been reworked to a 30P. Now that I switched to a fresh 200 with some bolt on mods done, I am going to need a few more inches of pitch. Any suggestions on what RPM range I should run. I want it to go over the stock range. But I definitely don't want to be spinning this motor to 7k.

Curious. Conventional wisdom is that you can only go up perhaps 2" by having a prop re-pitched, but your 26 is faster than your 30 at 5500 rpm. Is your current prop part number on the attached chart? Is it really a 26? What is your max speed and rpm with the 26?

Overhub surfacing props that have worked well on my SS2000: Drag 4, Hydromotive T4X, small ear choppers, Hill ET copy, Hoss Triton
Through hub surfacing props that have worked well for me: Trophys, Hydromotive

I agree that the Promax would be worth a try. You don't see a lot of Bravo's on smaller boats. ETs are good for a lot of people.

Click image for larger version.

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**skialot2** · 05-23-2024, 11:18 AM

Originally Posted by David

Curious. Conventional wisdom is that you can only go up perhaps 2" by having a prop re-pitched, but your 26 is faster than your 30 at 5500 rpm. Is your current prop part number on the attached chart? Is it really a 26? What is your max speed and rpm with the 26?

Overhub surfacing props that have worked well on my SS2000: Drag 4, Hydromotive T4X, small ear choppers, Hill ET copy
Through hub surfacing props that have worked well for me: Trophys, Hydromotive

I agree that the Promax would be worth a try. You don't see a lot of Bravo's on smaller boats. ETs are good for a lot of people.

I agree, conventional wisdom say 2" on a re-pitch. Yes. It is a big ear chopper 48 89858 A-4 26P. I never had it as a 26P. On my Glastron with my 135 it ran 65MPH @ 5500 RPM. That translates to around 16% slip. If it was a 26P slip would be 4%. But that motor did not have a LWP. I ran it with the prop buried. The shaft was around 3 or 4 inches below the keel. With a LWP I probably could have got another 4-5 MPH out of it. I only used it once on the Checkmate and I never got a top speed with it. Now it's way too small for the 200 to get a top speed reading.

**skialot2** · 05-23-2024, 11:40 AM

Originally Posted by rjdubiel

is that the 40 amp with the heavy flywheel? If it is stay under 7k, don't hold it all day at WOT. Now if its 16 amp with the lighter flywheel or even get a lightweight flywheel and you can turn it harder for WOT runs but still, don't go 15 miles WOT the whole way! trying to prop for 5600 or 6000 rpm is tough as you have to go so high on the pitch like you think but the take off will be horrible. Find the prop that gets you 6800-7K at max speed if you have 40 amp. if 16 amp see what it will turn WOT, maybe it will make it to 8K but I doubt it.

It's the 40 amp stuff with the heavy flywheel. I think I want a prop that will let it spin about 64-6500 RPM. If I can get enough control to hold it open for 1 minute, I will be happy.

**David - WI** · 05-23-2024, 12:26 PM

Originally Posted by skialot2

I agree, conventional wisdom say 2" on a re-pitch. Yes. It is a big ear chopper 48 89858 A-4 26P. I never had it as a 26P. On my Glastron with my 135 it ran 65MPH @ 5500 RPM. That translates to around 16% slip. If it was a 26P slip would be 4%. But that motor did not have a LWP. I ran it with the prop buried. The shaft was around 3 or 4 inches below the keel. With a LWP I probably could have got another 4-5 MPH out of it. I only used it once on the Checkmate and I never got a top speed with it. Now it's way too small for the 200 to get a top speed reading.

Are you sure you have 1.78 gears... the small XR6 gearcase? The big-ear chopper had about 3% on my HST.

**skialot2** · 05-23-2024, 02:42 PM

Originally Posted by David - WI

Are you sure you have 1.78 gears... the small XR6 gearcase? The big-ear chopper had about 3% on my HST.

I do not have a small XR6 1.78 gearcase. The 135 I had on my Glastron was a 2.0 gear ratio. The 150 also had a 2.0 gear ratio. Only my 200 has the 1.87 ratio.

**Carter Powell** · 06-01-2024, 07:57 PM

Are you SURE that you don't have 2.00 gear set in the lower. The numbers just don't work out.

Carter Powell

**dnelson964** · 06-10-2024, 09:23 PM

I have a rare to find, original Spinelli star 4 14.5 X 28.5 small shaft I can sell you. Still in like new condition.
Has great lift and holding power and very fast top end speed.

**skialot2** · 06-12-2024, 11:05 PM

Originally Posted by Carter Powell

Are you SURE that you don't have 2.00 gear set in the lower. The numbers just don't work out.

Carter Powell

Yes. It's the preload pin unit I rebuilt from a 1981 225. 15 tooth pinion gear. 28 tooth forward/reverse gears.

**skialot2** · 06-12-2024, 11:34 PM

I finally got out on the boat again. I think the tach may be off a little. I tried all the different settings. Only one setting is even close. My prop slip number just does not add up. I can see in the video I do hit 7000 RPM. and my phone GPS says a max speed of 68. That is a slip of 36%. Even if the prop wasn't modified and still a 26P it would be a slip of 26%. Got some video with a good look at my gauges. Around 4:44 of the second video you can see 7000 on the tach, and several other spots. Does it sound like 7000RPM?

1989 Checkmate Spectra 171 (youtube.com)

1989 Checkmate Spectra 171 (youtube.com)

**David - WI** · 06-12-2024, 11:38 PM

Something just doesn't add up. I've seen actual tach error of 200 rpm @ 6400... but that's not enough for what you're seeing.

**skialot2** · 06-12-2024, 11:49 PM

Originally Posted by dnelson964

I have a rare to find, original Spinelli star 4 14.5 X 28.5 small shaft I can sell you. Still in like new condition.
Has great lift and holding power and very fast top end speed.

I appreciate your offer. But I really don't think I can use a 28.5 pitch. But I would love to try it.