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offshoredrillin 12-29-2004 09:12 AM

Re: New motors and prop question
 

Originally Posted by offthefront
So if I go from my 454mags to 502's I would gain 3 mph ? Makes me feel better :)

I bought my boat the way it sits, the previous owner did a great job, my 502's came out of a 95 scarab and are EFI. I might be able to get a couple more MPH out of it with diff props, (5 blade?), kinda like the 4 blade bravos though. Had my mechanic do a couple things that he highly recommended, seperate battery switches and minor wiring upgrades to not send codes to the comp. i still have the silent thunder on mine, he did the earlier posted mods to them and I still have a decent sound and can hear the stereo. I'm seriously resisting the urge to go the horsepower route, as I have with all of my vehicles, I just dont have time to work on them. Harley is done, have a 95 supercharged 1500 for sale if anyone is interested. Sending the chev convertable out to Troy Trepanierand the custom lowered dually is done as well.
I think I'm going to go with factory HP 419 3 525 SC's and leave it at that, maybe diff props once I see how it handles. I'm going for all out reliability now... Got towed in 30-40 times too many on my Donzi. Besides, having the 419 puts me in a better position to use my screen name on the annual stripper cruise :D

f311fr1 12-29-2004 08:16 PM

Re: New motors and prop question
 
My '89 F311 with 468 CU IN blower motors had right at 600 HP per side. Marine Machine full hyd steering, Bravo 1 with nose cones, Hydromotive 28 pitch 4 blade Intimidaters. It would run 82-84 MPH all day long, or as long as you could stand to see the fuel gage drop. Best run was 87 on GPS.

DustinM 12-29-2004 09:25 PM

Re: New motors and prop question
 

Originally Posted by f311fr1
My '89 F311 with 468 CU IN blower motors had right at 600 HP per side. Marine Machine full hyd steering, Bravo 1 with nose cones, Hydromotive 28 pitch 4 blade Intimidaters. It would run 82-84 MPH all day long, or as long as you could stand to see the fuel gage drop. Best run was 87 on GPS.

Good to know. How did it handle at speed? How much of a difference did the nose cones make?
I will deffinatly start with Hydromotive props, but not shure what pitch yet. Boat mostly on Lake Powell at 3600' elevation which robs 7 mph from top end with same prop at Lake Havasu. About 800' elevation I think.
If I can max in the low 80's then I can cruise in the low 60's and that will have all my friends boats working hard to keep up with the cruise.
I wont get started on the motors for about 8 weeks but will post pics of progress.

boatman747 01-05-2005 12:20 PM

Re: New motors and prop question
 
I have wags old 311 with new 540,s abt 600 hp each. I have 30 inch bravos on there now. I have seen 79 mph at abt 4900 rpm with plenty of throttle left. Have not tried hydros yet but plan to this spring. I anticipate an 85 mph boat at best.By the wayjeff shes still as pretty as the day I drug her home in the snow !!! haha

f311fr1 01-06-2005 10:06 PM

Re: New motors and prop question
 
The Hydromotive props worked the best of any I tried. However you might think about the new 5 blade Merc's. Talk to Tom @ Hydromotive and MAGICFLOAT. The 311 loves stern lift IF you have enough power to carry the nose and spin the props. 600 HP 540's in this hull should work very well. Eagle makes a 540 rotating assy for GEN 4 and Gen 5/6 STD deck blocks that is very affordable. I used them on my son-in-laws Sonic and they worked very well. DO NOT SCRIMP ON THE HEADS.

boatman747 01-10-2005 11:37 AM

Re: New motors and prop question
 
DO not skimp on the heads is a true statement! I have gm rect. ports, Thats seams to be my biggest delema on the exhaust side. And I will try the 28 hydros myself.

milll36 02-07-2005 01:22 PM

Re: New motors and prop question
 
Hi im interested on changing the engines to a SR-1 311 that i just bought. The engines where i think the originals one the 454. But they havent used since 7 years ago so they are stuck inside. Please if you can help me find some options and where to buy it for a good price, i will apreaciated.

Formula Outlaw 02-07-2005 02:56 PM

Re: New motors and prop question
 

Originally Posted by milll36
Hi im interested on changing the engines to a SR-1 311 that i just bought. The engines where i think the originals one the 454. But they havent used since 7 years ago so they are stuck inside. Please if you can help me find some options and where to buy it for a good price, i will apreaciated.


Go with a reputable engine builder who people on this Board can testify to. I'm planning on repowering Outlaw within the next year to about 625 hp per side with N/A motors. Too Old @ Trick Marine, an advertiser here on OSO has a good contact for an affordable engine builder. That is who I am going to use.


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