I do like the way an XB sounds. Nice motors.

91 min octane. I always run 93 from a Shell station that turns their gas. You also have to take in to consideration the additives we all have to use with the carp ethanol gas. Quickleen and Quickcare in every tank too! It adds up!!

Me too! They definitely have a unique throaty-ness to them!

I had the exact same motor on a 2002 21' Bullet. Those XBs are awesome motors but do love the fuel. I ended up selling it in 2006 and put on an 06 MERCURY 250XS Racing Motor. The XS consumed about half the fuel and actually ran 1 MPH faster (86.1 was the fastest on the Bullet). Idle to upper mid-range is where it really shines. WOT they still use quite a bit, but still not quite as much as the XB.

The new XS and PRO XS motors are even more efficient today and have the same power. They don't sound as good as the XB but are better or as good in every other aspect. They will save you a lot of money at the pump too. They only require 87 Octane (PRO XS).

Since then I've had 3 or 4 PRO XS motors and they've all been very stout and reliable. If you're looking to make the switch, you won't be disappointed.

Hope this helps.

Here's a real world comparison on a recent trip to Sam Rayburn. I'm running a Z21 with a 250 Verado and my friend is running a Z20 with a 225 Yamaha HPDI. He had never seen the lake before so he basically followed me everywhere. In 2.5 days of fishing I burned just under a tank (about 22 - 24 gallons) and my buddy burned just over a tank (about 28 - 30 gallons). This included one long run from the dam up to the Deer Stand and back.

I used to own the exact same boat you have. The XB loves high octance fuel and oil and will consume it at a very rapid rate. I averaged around 2 to 2.5 mpg. I now have a 2004 250xs motor with the 1.62 gears and can get upwards of 6 mpg when just cruising. That's according to the smartcraft. Which is not compatible with the xb motor. The proxs is NOT as stout as the xb motor. Don't let anyone tell you otherwise. You have one of the baddest motors mercury has ever produced. Enjoy and take care of her and she will treat you well.

thank you all for your info. My boat is 12 years old and i take very good care of her. Truth i guess is i am getting the itch for a newer one but when mine is paid for with new seats, graph, never been outside for 1 night and i pull up to a 60k boat i laugh and say i dont get it. However still have the itch....at 42 years old now i don't really care as much for speed as i do fuel milage. I do want the best 250 motor for that moving forward in a yama or merc. Under no circumstances will i own another RUDE. No need on even trying to convince me, i had the FICHT motor (yes i am aware it's a diff motor now but no way will i go that route due to resale value). My comment is not to offend just stating based on MY 2 options which is best?

If you want better fuel economy then switch out the 1.75 gears for the 1.62's. You will have to re-prop and the Holeshot will be slower, but with the right prop that won't much of a difference.

I had an XB, now have an XS... The XB has a higher fuel curve than the 300 promax... your mileage will double vs XB, if you stay away from wide open on the opti's(WO they are really close fuel delivery). The XB is solid motor and not as finicky but if you fish alot, you can make up alot of money towards a payment for a new motor.. I hated worrying about getting fuel all the time.

Man that new Nitro sounds more impressive every time I hear of you speaking of it. God Bless

Sad, but VERY true. Man these new rigs are EXPENSIVE!!!
God Bless

I had a 1997 225 EFI merk that I bought new with a lot of hours on it ,I replaced it with a 250 pro xs and I believe that the new motor gets about 30 percent better fuel econmy driven the same way I have always driven it.hope this helps

I had an XB, now have an XS... The XB has a higher fuel curve than the 300 promax... your mileage will double vs XB, if you stay away from wide open on the opti's(WO they are really close fuel delivery). The XB is solid motor and not as finicky but if you fish alot, you can make up alot of money towards a payment for a new motor.. I hated worrying about getting fuel all the time.

I feel your pain, I have the same motor. 2 years ago I installed a fuel flow sensor and gauge so I could see just where it burned the most/least fuel. 3200 revs is the sweet spot on my XB, which is about 34 mph. It will get around 3-3.5 mpg at that speed.

Cheers,

George

Just remember, these motors were not designed to run at low RPM's. They're racing motors. If your going to putt around, make sure to run it WOT at least a few times during every trip and especially at the end of the day. Proper warm-up and proper cool down is essential. Also, have your injectors cleaned and calibrated every 3 years ( preferably the entire induction system) and have it done by someone that has the means to calibrate the injectors at WOT. This is critical! There are VERY few places that have this equipment. European Marine and Brucato Marine have this equipment to do it properly.