496 MAG secrets?????
02-10-2004 | 10:17 AM
#21
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carevelle
Mines a 2002 Mag that had the sooting problem..The boats always seem to run faster than it shud..When we took it to have ECM changed it ran 69 on way over and 72 on way back.. THe ECM did something.The dealer did mention that the sooting problem was supposed to be only on the HOs.
BCO
Mines a 2002 Mag that had the sooting problem..The boats always seem to run faster than it shud..When we took it to have ECM changed it ran 69 on way over and 72 on way back.. THe ECM did something.The dealer did mention that the sooting problem was supposed to be only on the HOs.
BCO
02-10-2004 | 10:54 AM
#22
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BCO ---
SO, did the ECM / U change make the correction to the sooting problem??????
.....AND helped the speed???? SWEEEEEET!
ON WHICH BOAT DO YOU HAVE THE 496 BCO?????
I will be talking w/ HOUSTON and upsizing a pitch and having that prop labbed --- I think that will be my solution to a 70 mark.
SO, did the ECM / U change make the correction to the sooting problem??????
.....AND helped the speed???? SWEEEEEET!
ON WHICH BOAT DO YOU HAVE THE 496 BCO?????
I will be talking w/ HOUSTON and upsizing a pitch and having that prop labbed --- I think that will be my solution to a 70 mark.
02-10-2004 | 04:01 PM
#24
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From: Minnesota
Exactly what prop are you running? I believe Mirages come in 21 or 23. According to caravelle's web site, they tested a 260 with a 502MPI(415hp) and a 21 mirage and got a top speed of 61.8.
http://www.caravelleboats.com/Boats/...test_page.html
Brian
http://www.caravelleboats.com/Boats/...test_page.html
Brian
02-11-2004 | 01:47 PM
#25
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caravelle
Yes it corrected the sooting problem..I have 2002 288 sunstaion..The speedometer must be off because the Mag is not supposed to run that fast..and i don`t think i accidently got a HO in disguise..If they put a HO ecm on it, i don`t know,without the ho cam it probably wud not make a diffrerence, but it did run better after the change.
BCO
Yes it corrected the sooting problem..I have 2002 288 sunstaion..The speedometer must be off because the Mag is not supposed to run that fast..and i don`t think i accidently got a HO in disguise..If they put a HO ecm on it, i don`t know,without the ho cam it probably wud not make a diffrerence, but it did run better after the change.
BCO
02-11-2004 | 03:26 PM
#26
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Caincando1
Factory 21 Mirage ran 63-65mph. 22 Bravo currently and running the 67 mph. Am now considering either a 23 Mirage or labbing the 22P Bravo?!?!?! Any input???
I feel the Mirage benefitted me the most; lost the hole shot w/ the Brave -- but, am concerned that I may lose speed or begin to REV out on the Limitter??? I run out ahead of 280 Silencer until he sneaks around me @ 72mph --- I NEED 70MPH! or am willing to try all the cheap tricks?!?!
Factory 21 Mirage ran 63-65mph. 22 Bravo currently and running the 67 mph. Am now considering either a 23 Mirage or labbing the 22P Bravo?!?!?! Any input???
I feel the Mirage benefitted me the most; lost the hole shot w/ the Brave -- but, am concerned that I may lose speed or begin to REV out on the Limitter??? I run out ahead of 280 Silencer until he sneaks around me @ 72mph --- I NEED 70MPH! or am willing to try all the cheap tricks?!?!
02-12-2004 | 03:55 AM
#27
Charter Member # 55
Joined: Oct 2000
Posts: 20,244
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From: Omaha/LOTO
Do NOT wax the bottom of the boat. It will slow you down if it does anything.
Labbing the prop is your best bang for the buck.
Do your tips have mufflers????
If so, going to straight out tips might be worth a mph.
Labbing the prop is your best bang for the buck.
Do your tips have mufflers????
If so, going to straight out tips might be worth a mph.
02-21-2004 | 11:12 AM
#28
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From: San Diego, California
Carravelle260
According to GM who is Mercury's supplier, the fordged cranks were only used early in the program on the motor and were made by Kellog Machine. Most were used in 425 HO's and the HP3's that GMC raced in Factory class thru Innovation. GM tested both and found the cast was nearly the same strength as the forged and a lot cheaper, so they dropped the forged crank in all motors. The only way you can verify is to drop the pan and check the casting or fordging numbers. As for forged pistons in any 496 is not true the only piston made by GM is a cast hypereutectic type and its the same in all motors unless their rebuilt with an aftermarket piston. By the way the new 496 engines produced after September 2003 now have full floating piston pins to help strenghen the motor and eliminate cold engine piston slap. Hope this clarifies the issue.
Raylar
According to GM who is Mercury's supplier, the fordged cranks were only used early in the program on the motor and were made by Kellog Machine. Most were used in 425 HO's and the HP3's that GMC raced in Factory class thru Innovation. GM tested both and found the cast was nearly the same strength as the forged and a lot cheaper, so they dropped the forged crank in all motors. The only way you can verify is to drop the pan and check the casting or fordging numbers. As for forged pistons in any 496 is not true the only piston made by GM is a cast hypereutectic type and its the same in all motors unless their rebuilt with an aftermarket piston. By the way the new 496 engines produced after September 2003 now have full floating piston pins to help strenghen the motor and eliminate cold engine piston slap. Hope this clarifies the issue.
Raylar
