Amt 30 - 2.5 Or 300x
#2
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Joined: Feb 2001
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From: houston tx
I would wait and see what merc has for the verado at the miami show. If nothing good comes out, Id go for the 300x, just cause you dont have to mix the oil and gas and you get a warranty.
Curtis
Curtis
#4
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I Spoke To A Guy That Either Raced Or Rigged The Hulk Boat And He Said The 300x Is To Heavy. What's The Difference Between Them... Torque, Midrange Can You Hold The Throttles 70-80% For Some Time. M I'm Coming From Blower Motors And I Think I'm Done With Worring If Im Gonna Get Back To Land. Thank You For Your Quick Responce. By The Way, What's Your Opinion On The Amt 30?
#5
Originally Posted by rvrtricks
I Spoke To A Guy That Either Raced Or Rigged The Hulk Boat And He Said The 300x Is To Heavy. What's The Difference Between Them... Torque, Midrange Can You Hold The Throttles 70-80% For Some Time. M I'm Coming From Blower Motors And I Think I'm Done With Worring If Im Gonna Get Back To Land. Thank You For Your Quick Responce. By The Way, What's Your Opinion On The Amt 30?
check out the amt/spectre/skater thread on here somewhere.......
#8
The 2.5's are about 100lbs lighter per motor. I have a 28 Skater which is quite a bit lighter than an AMT, I know on my boat 2.5's provide you with a lot better balance. However, unless you run the boat in heavy seas in racing conditions, I can not see why that would be a major issue. I also cant imagine the AMT being affected as much as the 28 Skater being the AMT is heavier. The 300x's will be faster unless you are talking about 2.5 race motors that have been modified (which if you are worried about realiability you dont want!). The 300x's should last at least twice as long before needing to be freshened up. If the 300x's are anything like the 300 promax's I have, the 2.5's will give you quite a bit better fuel mileage. Most outboard guys agree you cant beat the sound of 2.5's. The 300x's will rev to 6800, the 2.5's to 8000 - 8200 rpm, obviously different gear ratios 1.87 for 2.5's, 1.62 for the 300x's. All things considered, I would go with the 300x's. AMT is an awesome boat, good luck!!
#9
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Joined: May 2003
Posts: 92
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From: cayman islands
Had em all.....the 300xs are alot more forgiving at the docks, quieter, shift seamlessly, etc. if you just want top end and not alot of rough water(4-6 footers), the 280s are alot better balanced and more responsive for but about 4 mph slower on a 30' Spectre. If you want to go to the extreme bolt on some 2.5 drag motors (335 hp) for the ultimate in response, acceleration and top end...I bolted on 3. Drag motors are the ultimate performance outboard but come with a price....driveability at the docks. I did notice that they are alot more manageable at idle speeds, starting , etc. since I swapped out the a13 Mercury boxes for the Brucato PCUs.
As far as reliability, the 2.5 motors are race motors and are designed to be run at high rpms for extended periods. Most people who have problems with them are either running too lean an egt or are overheating due to engine height/water pressure. The 2.5s can also be made more reliable and a lot more powerful with the touch of after market tuners such as Diamond Marine who lighten the cranks and flywheels, balance and blueprint, port, etc. The last motor they did for me was on an Allison and it put out 374 hp peak and was still making 355 at 9600 rpms!
As far as reliability, the 2.5 motors are race motors and are designed to be run at high rpms for extended periods. Most people who have problems with them are either running too lean an egt or are overheating due to engine height/water pressure. The 2.5s can also be made more reliable and a lot more powerful with the touch of after market tuners such as Diamond Marine who lighten the cranks and flywheels, balance and blueprint, port, etc. The last motor they did for me was on an Allison and it put out 374 hp peak and was still making 355 at 9600 rpms!
#10
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Joined: Dec 2002
Posts: 959
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From: chesapeake bay md
Dreamboater I am suprised you commented on fuel mileage. The 300promaxs on my motion are Very good on fuel. I am not being a smart a** but I wonder what is the deal with your set up? I will be very interested when you have it all figured out


