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500 Caddy reductions

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mickey5978

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Anyone running a 500 caddy reduction? I would assume 1.7:1 CH3 would be the best for me. Got a hot caddy for DD and it is not good for my boat, evidently. Got stuch on a flat rock bed in the river in 4 inches of water! Also found out the hard way I could not pull onto a small gravel bar just inches out of the water! Gonna rebuild caddy to run higher rpms with different cam and head, intake and such. should push around 450 HP and 4500 rpm. Got a 3 blade sensenich hub. What powershift blades would work. Faron, you may be one to answer. Aren't yalls boats with 454/502 running that kind of prop? Suggestions or one's experience from anyone would be GREATLY appreciated. Trying to figure out how big I can go on the prop!
 
I just recently put a 2:1 gear box on my Caddy with a three blade 78" Sensenich. I run with another boat that has the 1.77:1 CH3 spinning a three blade 78" Powershift. Both setups seem to do extremely well. I intended to run about 5,000 rpms with the 2:1 but I pitched my blades to where I am hitting about 4250 max rpm and the boat is performing above and beyond what I expected. I can cruise at 2100 - 2200 rpm with a 15' X 7.5' Alumitech hull with two "large" adults. :D
 
A gear box will out perform the belt drive there is no doubt about that. I have owned over five gearboxes and have a friend with 6 or 7 years of service and over 1,000 hours not one box has had a single problem and most of them have had 500plus HP motors on them.
 
Just my 2 cents if you build a caddy , for the rpms , go a little more on the box I went with a 237 but ,I got a bigger prop , still running 5000 ,less prop rpms about 2000 -less gas,less sound !I am running 2.3 80 in blaster three blade looks like a PS maxius but not as hard to turn !A lot of prop to twist ,still :D I built the motor to turn the prop not the prop to fit the motor !
 
Rods pistons ported heads balance everthing decked cam for 2500 to 5200 bb block roller rockers 1,7 ratio ! 2.19 intakes 1.88 ex ! they say that rockers is a must springs too rods are on the edge but will work its who you talk to that the way you go ! sort of maggots or fishing worms !
 
I've got about the same into mine
Ross forged pistons +.030 (got a steal on these at 450.00 shipping included!...otherwise KB's were on the list)
1.72 ratio shaft rocker arms
Comp Cams 270H Magnum cam
BHJ Elasomer Damper
Ported and polished 76cc heads with 2.19/1.90 valves
Oversized double coil valve springs
Cloyes True Roller timing set
Balanced rotating assembly

I have been told about 5500 is a safe bet with stock rods. I wouldn't want to push it much past that.
 
my cady is almost identical to the last couple of posts but 6 degrees of advance for my cam cause i went dd.
 
The way these cads are set up they , are good , all rpm ranges, Makes a big difference in these over grown john boats :D Just remember you change one thing got to change some other things too . Not a big deal! But you will say damn . But when you are done ,more bang for the cubic dollar !I found out that you throw away them shorty headers and run some longer and smaller tubes to the collectors bottom and midrange grows wonderfully . thottle responce is priceless ! :D
 
FATBOY that has been my motto for years now. Run more box and more pitch you will end up turning less RPM's with much more thrust. I still have to prove this on a weekly basis I just gave up and do my own thing. Just about anywhere I go I can take 8 to 10 people and run places where allot of boats can't even go.
 
I am trying to decide between a gear or belt reduction. Is classic the only one who makes a gear reduction? Any help on who make the different drives and pro's and con's of eah would be great. Waterthunder, I know you like gear, why?
 
Singer and Rotator are your best two options. I find the gear boxes superior for three reasons.

1 they are far lighter
2 the come in high ratios that multiply your torque output most belts are only 2to1
3 with a belt drive the prop torques in the same direction as the motor thus causing sever torque roll. A gearbox turns the prop in the opposite direction of the motor thus preventing allot of torque roll
 
where are places to find these singers and rotators? I cannot find any info on the web for singer and only classic for the rotator. Do they (classic) make the rotator?
 
also just because max prop speed is a certain rpm does not meen that is what you go for.with a reduction unit you can spin bigger props so your push is going to be strong.not like a direct drive where you have to reach best prop efficiency to get your boat where it needs to be.fatboy0054 he has his the way i am shooting for big prop tall gear. and jdotson post
is good example too.he pitched his to lower his rpms with what he posted at cruise his prop is at 1000-1100 rpm and does what he wants with great expectations.1.77-1 is great for a caddy but 2.0, 2.19,and 2.38 is alot better i.m.o. max prop speed usually does not meen best performance.
 
Just my deal , Rotator is a little less cash comes with a soft drive . But I am sort of in favor of Mr bell evertime I go there if he dont have it . He tells me can you wait a few, I will make it . Never left with out stuff I need ! Pretty cool now days ! Never had a stinger ! Never seen one broke !Now days , like mr thunder says more box more twist .Most of us here now understand this a litte better now . Thanks to dave ! Most of the help you get here is honest ! We are all sort of foolish at times , But that keeps us sane!Its a learning thing ! great bunch of boaters here !We will have fix up in no time ! You got to buy a gear box from a dealer!No way around that :D
 
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