HELP! 21XD

[twohands25]

Just bought my first Bullet. It's a 1994 21XD with a 225 EFI and a 26P 4 blade Trophy. Only one of the four vent holes are plugged. Hole shot is TERRIBLE. When you first give it gas the rpm's don't climb fast at all. It feels like the prop is too big. Takes off real slow but as soon as the bow starts to drop you can feel the prop blow out. It feels like it does not have enough prop. I'm not a speed guy by any measure but I have had the boat up to 62mph at 5400rpm (I believe that was the rpm's). I would just like a better hole shot and if I can get speeds in the mid 60's, I'll be very happy. I can tell the motor is set real high but I don't know how to measure the exact height.I don't know if it's all in the prop or if it's prop and motor combined. I have had a few other old bass boats so I'm not totally clueless, but I can see clueless from where I am standing. Thanks for any help, Scott

[Greg Z]

Plug the 4 holes

[Rex1]

If it was my boat I would step down to a 23 pitch with some cup added or a 24 pitch. I
think from what you said about the hole shot, plugging all 4 holes is not going to help. Stay
with a 4 blade prop because when we try the 3 blade props they drop the nose of the boat at
WOT. Make sure the prop you have now is in good condition. Try different pitch props before
you get the one you are happy with.

[jayfaro]

Plug the 4 holes

He said the prop doesnt spool up with 3 open holes. This is probably the worst thing he could do. I personally think it’s too much wheel. I’d pitch down.

[twohands25]

Thanks Jay. I don't know much about this but it seems like I have too much prop and not enough prop all in a 10 second span.

[rambo274]

take the last plug out of the prop and try it.

Is that year 225efi a 2.5 or a 3.0 liter?

If its a 3.0 liter. I am going against the majority here and thinking that you do not have a big enough prop. A properly sized and vented prop would have both a good holeshot and topend.

I know this may not be and issue but, how much time and experience do you have with a high performance hulll like a bullet.

I think that should easily be a 70+mph boat.

[twohands25]

Thanks Randy. I have had a few bass boats (a couple older Skeeters and an old Ranger) but I have a pretty limited amount of high speed driving time. My last boat was a Skeeter zx210 with a 225 yammy. It jumped out of the hole pretty quick. Is there a way a mechanic can verify that I'm getting 225hp to the prop?

[jim813]

I have a 21xd with a 98 merc 225 Efi and am currently running a 26p trophy plus. I have two large and two medium PVS plugs. Having all four plugs out was definitely too much ventilation, and all four plugs completely plugged only worked with solo runs with a light load.

My current set up takes about 3/4 throttle to break over, then revs up to about 4500 rpms with two guys and full load.

Holeshot is is very dependent on load for me. One guy and a lighter load, and the boat comes out of the hole very quickly.
Three guys, full fuel, full livewells, and too much tackle, and its slow out of the hole.

Worse holeshot in the summertime, worse as the day goes on.

Prop to pad at 1.75" below currently. Best speed with two people and full fuel/live wells/tackle is 72.9mph at 5800rpm. Nearly full trim. I know the prop shaft needs to be higher but have not had a day where I just go out and test (I like to fish too much). I rarely drive above 60mph due to boat traffic and conserving fuel.

I had a bad holeshot once and was having poor performance from the engine, and something didn't sound quite right. I pulled the cowling and found a spark plug wire disconnected. Might be worth a simple check up on the engine to make sure it's performing at full capacity.