DMAX

Counting down the days til boating season up here in the north, God knows we're all foaming at the mouth after the winter we've had. . . Our season usually starts mid May, ends late September.
My question is . . . I have a 1994 336 Formula with 2 fresh Generation 6 502 MPI with fresh Bravo 1 1:50 with 25 pitch 3 blade Mirage props and gill exhaust. The boat came with 4 blade Bravo 1 24 pitch props, but gave the boat too much bow steer. So I replaced them with the 3 blade Mirage. Right now I'm seeing 67.5 MPH on GPS at around 5000 RPM. I've read other threads where guys with the same set up are running in the low 70s. I was wondering should I be running a bigger 3 blade? Does anybody have any ideas? Any input would be deeply appreciated.

CObarry

I'm running 26P 3 blade props on my '96 336. With stock 502's & exhaust, I get 72-73 mph on my GPS at 5100 RPM. On the '95-'96, Formula modified the hull to notch the transom, which probably accounts for the difference.

jaybird

That you Johnny? Hey did you ever GPS my props when you tried them?

DMAX

Hay Jaybird hows things down south.Today we got mid 80s going down to lower 50s tomorrow.gotta love New England weather,yes i did get a chance and the #s were the same.so whats up for boaten season down south?

DMAX

thanks for the input Cobarry much appreciated

jaybird

Things are going great. I've been out a bunch of times, and it's a totally different scene down here as you could expect. Tons of places to boat to. Great weather too. Been 70-80 most of the winter, if you could call it that!

The only thing I could think for you to try would be to get a hold of a set of 4 blade hydromotives for your boat. It would help lift the stern out of the water a bit more than the mirage which helps old Formulas. I am going to try a set when I get a chance. You can either call Throttle up in Tampa, or Hydromotvie directly and talk to them about a recommendation. Good luck with it!
-Jason

powerguy

I have a set of 22 hydromotives that I am going to try in a couple of weeks when I put the boat in the water for the season. I have 454 mag's on my 1993 vintage 336. Also have 23 mirage + props that I just had lab finished to add a couple hundred rpm and get rid of the cavitation that I get at around 2800 rpm coming up on plane.

Formula Outlaw

Hydromotive Quad IV's made all the difference in the world on my 89' 311. Gave me 7 mph more at cruise and 3 on top. (gps) 454 mags. Gets on plane effortlessly.

powerguy

Put my 336 Formula in the water yesterday and the 22p hydromotives were definitely the way to go for me. Will a full tank of gas (150 gallons) and with drives trimmed fairly deep I hit 4800 rpm but did not have my gps on to check the speed. Out of the hole was a breeze with no cavitation and I should be able to spin the props to 5000rpm with more trim and less fuel on the boat.

I had tried the 24 bravo 1 and 23 hydromotive before these props. Bravo 1 had great hole shot and cruise but was short on the top end. Hydro 23 could only spin to around 4500 rpm or so. I will post results with 22 hydromotives when I get back out on the water.

My boat has the 454 mag's so with 502' s the 23p hydromotives might be the right prop for you.

DMAX

Thanks to everybody who replied, but I'm going to stay with my Mirages, changing the props isn't going to give me the speed I really want (I'm sure you know what I mean). But the 24 Bravo 4 blades are for sale, if somebody wants to make me an offer. Also, I have another set of 25 Mirages for sale if anyone is interested. Has anybody ever added the after market billet flame arrestors for EFI motors? Is there any noticeable performance gain, or do they just look cool?