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fasttrucker
06-18-2002, 07:11 AM
master-merc. mech. says i should go to a 4 blade prop what do u think,502mag soon to be power-upgraded.headers,air intake,reprogramed computer. :confused:

Gary
06-18-2002, 07:53 AM
You are just determined to spend money on that new boat :D It seems that 4 blades do work well with step hulls. See if you can borrow some props to test before you buy

33 Daytona
06-18-2002, 10:36 AM
A 3 blade will give you a better top and sometimes you dont have enough power to turn a 4 blade at proper rpm. All you can do is test. In my case I have a 454 mag and I tried a 4 blade 24 pitch and lost speed because I can't turn the RPM. But then when I added a Whipple I couldn't use a 3 blade, it wouldn't get me on plane even a 27 pitch it would just cavatate. Get you engine mods done then worry about the props.

Bryan Tuvell 33ZX
06-18-2002, 03:32 PM
FASTTRUCKER, I was surprised you have a 3 blade on a single in that hull, as you look bak over data a few years ago they were common, today on a new one, same application would come with a 4 blade from Donzi.
I tried a 23 MP and it blows out ALLOT, especially in turns, and in the bay it would cause me to fall off plane in the mid range while working the throttles.

I am running a lab Bravo I with throttle left, I am in the hunt now for a 26 that I can make a 25 4 blade.
Bryan

fasttrucker
06-18-2002, 07:07 PM
just back from run,went to bay bridge.had my 3-blade prop recondition.so prop is nice and shiny. wink but it didnt go any faster,merc mech. says the computer whould not let the motor rpm up anymore than 5200. :mad: this is what is stamped on prop-48-13704-23p .so i guess its a 23pitch? :rolleyes: anyway gave my super-ace,master mech. down payment$$$$ and ordered k+m intake-flame erester.stanless headers,sending computer to az speed.shop for reprograming.new wires,cap,rotor,plugs{hotter-range],oil,filter,fuel filter.also keeping the silent-choice system but punching out the baffles in exhast tubes{remachine at machine shop} has a 4-blade/to try after upgrades.sounds cool :cool: should take a month or so will keep u posted. :p

Shanghied Again
06-18-2002, 08:37 PM
FastTrucker, The 502 is a good motor all the upgrades you are making is not going to add much, I have been in many discussions on Hp upgrades and the most you will get out of a 502 is 425hp that equates to about 1-2mph Not worth spending all that money on! Your motor is not a High Compression motor the exhaust will only add a 5% gain. The Computer and Ignition will let you go higher with the rpms but will not change the torque or the Hp of the motor, You can lower the prop pitch more rpms and the same speed! I talked with the best on this and they all agree. Either tear down the motor and build it or SuperCharge it. I have supercharged before and I had no issues. So next year my motor is going to be built tough. My brother in law has the 27ZX he tried everything to get that boat above 62MPH Exhaust/New MRD Ignition Computer chip and still didn,t see any gains. I too bought the Vortech Air Filter, Lab Prop, and my GPS reading is the same as one I bought my 26ZX 65.6 mph sometimes 66. I have seen 69 one time when it was cold and that was before the $175 Air Filter. We Procharged his 27 and he has been running the boat 2 seasons with a top speed of 75 Mph. Like my Mechanic says, Frank you have a 65 Mph boat no matter what you try its a 65 mph boat. When you are serious I will make it an 85Mph boat and save you money! Typhoon Performance Marine Home of the fastest motors ever built
42 Outerlimits 1050 hp each 120mph
37 Outerlimits 950/500 Procharged 110mph
22 Donzi ZX 510/454 Procharged 81 mph
38 Donzi ZR 850/600 each Vortech Charged ?

Home of Runnaway World Champion 3 years in a row
Typhoon Racing F-1 Apba/SbI Champion
Buckshot Racing
Kryptonite boats kilo holder single engine procharged Typhoon motor 111 mph out of a 27ft.
When they speak I listen. As my wife says stop waisting money! just do it the right way. Just my 2 cents

Bryan Tuvell 33ZX
06-18-2002, 09:07 PM
One word of advice, if you add all that at once and have problems, trouble shooting will be HARD, another free lesson learned from me, add one at a time, plus you will never get the prop pitch right at this pace.

I wish you luck, be sure and share all data with us and photo's too.
Bryan

BigGrizzly
06-18-2002, 10:05 PM
Frank is correct in all he says. for 3 mph you need all that and a prop. here are other props besides Bravo1 and Marage Plus (I no longer use either). I have a 80+ mph 22 and it took a lot of money and time and several different props to get there. I don't agree with the 4 vs 3 blade to get on a plane its the type of prop. Its like saying a 4 blade is faster or slower than a 3 blade- its the design of the blade. You have only two choices, 1)gain 1 mabe 3 mph with small mods combined 2)or go big time with big power. Yes my engine is supercharged.

Randy

fasttrucker
06-19-2002, 08:26 AM
good advice will be off-line till 26 or 27 got to trk to pay the bills.thanks wink