Maiden Voyage

[DonziBuoy]

I finally got my 1974 16 ft ski sporter in the water over the weekend, after rewiring the gauges and putting in a throttle/shifter cable, I dropped it into Hempstead Harbor located outside NYC on the LI sound. The prop is an Ellis, 3 blade, 20" pitch bronze.Although at the spindle the prop appears smaller than the Volvo 270's lower unit, by about an 1 1/2" less in diameter. I am guessing the extra whetted area allows for greater thrust(?) - would like to hear anyone on that if the hub size makes a difference on the early volvos. My fear was this prop would have a cavitation problem, I couldn't tell, as the speed I got was unbelievable. The engine is a completely worked over Chevy 350, which as less than 50 hours on it. I do not know what the HP is, and wonder if there is a good way to guess from prop and speed - someone out there have an idea what the 16 should do with a 350?
Although initially, I thought this prop would be only good for just pulling skiers, I was amazed at the speed this boat did. I am planed at 1900 RPM, and it is incremental jumps in speed from then on. I am flying at 2900 and then She just comes alive at 3000 RPM I was guessing I am well over 45 mph (speedo said 40MPH), as that is when my eyes start to tear. 3100 RPM I am going considerably faster, and quite frankly the 1000 RPM difference made me stop there. My red line is 5500, and I do not know if I am "man enough" to go the rest of the way.
The 74 has a "lip" at the end of the strakes, keeping the boat planted - she got up and rode high right over everything except the 4- 6 ft wakes. Beautiful riding, much better than my 95 18 classic.
THe big problem I had, was that the clutch going into gear at low speeds, I understand that the Volvo uses a cone type clutch - even with this shallow prop, at 1000 rpm, I am clipping along at around 15 mph - very hard to do dock side maneuvers at that speed.

[zelatore]

even with this shallow prop, at 1000 rpm, I am clipping along at around 15 mph - very hard to do dock side maneuvers at that speed.

Er, 5 mph maybe? I haven't done the math, but I think you'd need a bit more that 20" pitch to hit 15mph at 1000 rpm :wink:

[VetteLT193]

with a 270 and a 20 prop you shouldn't be moving fast. Check your tach. maybe you are idling higher than you think?

if not, maybe the prop is bigger pitch than you think. I'm pretty sure that 270 came in higher ratio's, a bigger number than 1.5, so it should move pretty slow at idle.

[Tank]

Congrads sounds like you had fun and that’s what its all about!
I have bin playing with props on my St Tropez, and yes 3mph at the dock seems very fast.
I to had a small hub on the Ron hill prop 15x21=cup and very fast dockside.
I think the OD and or cup of the prop have a lot to do with slip and idle speed? OH Griz whot do you think?
You need to ask a friend to lend you there gps.
There are some engine programs but you need all the info bor, stroke, com, cam ,valve size and so on. stock Chevy parts + cam if you lucky 275/350 hp just my 2ct.
Keep us posted and stay safe and have fun hope you are warring your PFD on the speed runs?
Tank

[smbarcelow]

...someone out there have an idea what the 16 should do with a 350?

So far, I've gotten 59 MPH (on GPS) with my 16/350/270 combo. I haven't gotten the prop selection right yet. I can spin this one well past 6,000 RPM's if I'm not careful. With about 350 HP and a well-matched prop, you could expect to run around 65 MPH (my guess).

[robertbj]

THe big problem I had, was that the clutch going into gear at low speeds, I understand that the Volvo uses a cone type clutch - even with this shallow prop, at 1000 rpm, I am clipping along at around 15 mph - very hard to do dock side maneuvers at that speed.


Just a thought. How about turning the idle screw out a little on the carb. It's hard to remember (It's been a couple of years since it has been in the water) but I think mine idles at 8 or 900rpm.

[DonziBuoy]

I am idling at 800 RPM. She won't go into gear until I push the throttle to about 1000 RPM. When I try to pull back slightly, I go back out to neutral. I have adjustd the cable on the outdrive side to be "in the middle" of forward and reverse. My outdrive is a volvo 270.

[RedDog]

I am idling at 800 RPM. She won't go into gear until I push the throttle to about 1000 RPM. When I try to pull back slightly, I go back out to neutral. I have adjustd the cable on the outdrive side to be "in the middle" of forward and reverse. My outdrive is a volvo 270.

If adjusted correctly, it should go into gear without opening the carb.

[MOP]

I am idling at 800 RPM. She won't go into gear until I push the throttle to about 1000 RPM. When I try to pull back slightly, I go back out to neutral. I have adjustd the cable on the outdrive side to be "in the middle" of forward and reverse. My outdrive is a volvo 270.

I can tell by what you are describing you do not have the slide removed from the carb or improperly setup. Look at this link I just posted!

http://www.donzi.net/forums/showthread.php?p=526327#post526327

Phil

[BigGrizzly]

The going into gear is a cone clutch issue, and is easily repaired. Your prop is too small with that engine. The smaller hub will give you some cavitation issues but not bad because you don't have prop exhaust. That old ellis has been around for years-40 or so no longer in business. Works OK, nothing special. Get more seat time and some GPS speeds and we can help out better.

[BUIZILLA]

cable..

[Tank]

Tanks MOP Ineed to look at this on mine!
Tank

[mattyboy]

yes cable or adjustment on shifter linkage end, my volvo shifted very smooth and would engage into gear( F or R) as soon as the shifter was deflected out of the "notch" for nuetral the old 351w would idle at around 650 and I never had any speed issues when docking. i spun everything from a 19 pitch to a 26 pitch never any stalling on a 1.6 250 My throttle also had alot of movement until the gas was actually applied if nuetral lock was 12 O'clock the gas was not applied until 2:30 - 3 O'clock

damn i miss that boat

[DonziBuoy]

Phil, So I will look at the linkage on the throttle? Also, where does one adjust for the cone clutch?

THanks all, as always great advice.

Jim

[Kirbyvv]

I had the same issue after putting my volvo drive back on one time. Like Buiz said...cable adjustment.

[DonziBuoy]

So far, I've gotten 59 MPH (on GPS) with my 16/350/270 combo. I haven't gotten the prop selection right yet. I can spin this one well past 6,000 RPM's if I'm not careful. With about 350 HP and a well-matched prop, you could expect to run around 65 MPH (my guess).

I have seen your pictures of your boat and ours are the same color scheme. Your light honey bottom, is it painted or gel coat? Mine has been painted, with the original color being the orange/tangerine color. I have 2 more props which spin the other way (right) and will be trying them out. One is a 24 in 3 blade (chopper) and the other a michigan 3 blade 14 1/2 X 21. Grizzly says my props are not right for the boat, so, I am going to trythese two. I also noticed you have a stainless Volvo, which certainly looks nice on the boat.

Jim

[smbarcelow]

Mine is actually white gel coat on the bottom. I think it just looks like light honey in some of the pics. (Plus, it could use some more buffing to brighten it up.)

The Volvo Ultra I have now (I think that's what it is) handles real well but I can overpower it too easily. Griz has mentioned trying a Solas 23 on mine. I've still got to pull the cone off and find out what I'm running. Nothing is stamped on the outside. I also need to figure out my drive ratio. Once I have that info, I'll be more able to select a good upgrade.

From the reading I've done on this site, prop selection is the key to performance, handling, safety, you name it. It's all new to me. I grew up driving a squirt boat. I'm still learning.

I do, however, have the engine running real well now. I've got a little more tinkering to do with the Holley to get rid of a stumble during heavy throttle transitions. I'll probably play around with larger accelerator pump nozzles and cam profiles and get it dialed in nicely.

[mattyboy]

SMB,
if there's a tag on the top of the drive that should tell you what ratio you have it should have 270 XXXXX A B C or D


some of the newer 290 have it stamped in the drive casing

most likely a B but if you are turning 6000 there's a chance you might have a C or even worse a D




A= 1.3:1
B= 1.6:1
C= 1.8:1
D= 2.0:1

those are base numbers rounded down

[Canvas Man]

[quote=smbarcelow;526455]Mine is actually white gel coat on the bottom. I think it just looks like light honey in some of the pics. (Plus, it could use some more buffing to brighten it up.)

Try using a product called "Rust-Aid" for those brown bottoms. I get it at Home Depot in the Plumbing/Sprinkler section. Its really made for removing rust water stains from your house or sidewalk caused by the sprinkler system, but it works wonders on brown water stains on gel-coat. Spray on/ Rinse off. Try it---You'll never go with out it.

[smbarcelow]

Thanks, Matty. Once I get a look at the tag, I'll let you guys know what I find out. (That, and the prop.) With all the wrenching I've done over the last season and a half, I've been trying to avoid working on it too much and just enjoy the fact that it's finally running well...keeps my wife much happier. ;)

Thanks for the tip, CM. I'll look for it next time I'm at Home Depot. It would be nice to get the hull shining again. :)