I purchased a 1999 280 Silencer over the winter as a project. It had a blown up 454 Mag Mpi. I had a new motor built and got it installed. Now i'm having what I believe to be ecm/efi issues. My question is, what prop is everyone else running on their stock or mild built 454? How is the holeshot? Currently I am running the previous owners 24 bravo 1 4 blade. The boat comes out of the hole like a rock untill it hits 3000 rps, at which point it takes off like a drag car! I have tried a 22 4 blade. It didn't help at all! Any advice would help greatly!

Trim tab use is a must on these 280's, don't be afraid to drop them all the way down every time.....or add 700 hp under the hatch...

He's not kidding, didn't take me long to figure that out. Drop those tabs all the way every time.

You bought the '99 out of Detroit with the engine issues didn't you? I was contemplating buying it and having Crockett fresh'n the motor and reselling. Nice boat!

Thanks for the input, guys. The horriable holeshot is with the tabs and drive barried! Everyone I talk to around here runs a 24 bravo on their stock 454 mag and gets a decent holeshot with the tabs/drive all the way down. The engine I have now was dynoed at 505hp 540 lb/ft torque. It should do a little better out of the hole than a stocker, I would think. Yes, it is the boat from the Dryden area with motor issues. Be glad you didn't buy it, the last owner was a complete hack!!! I replaced the steering cable, helm assembly, gimbal ring, bellows, upper outdrive shaft, and a **** load of misc things! Also replaced all the trailer tires (dry rotted) bearings (lost one on the e-way) brake lines (cobbled), and am about to adjust the bunks properly. Had to buy a complete engine because the mains were cracked. Someone had replaced the origional 454 mag with a non mag cheap reman bottom end. It has been a challange to say the least. At least I know its right now, and I'm not in it too bad price wise. It will be for sale soon though, there isn't enough room in the cuddy for the Mrs. She agreed to come off some money to go a little bigger! First, I have to work out the ECM bugs.

I would try a labbed Bravo 26, you'll lose some holeshot

I have the same boat but have the 502efi I run a bravo 1 26p 4 blade on mine...cant complain about hole shot it does everything I need it to do....

B1 24 should be about right.How many rpms will it pull on the top end? You've got the same HP as a merc racing HP500efi and the 24 is what my 280 came with.Look at the dyno sheet and check HP and TQ numbers down that low. Maybe running too rich on the low end? You mentioned efi/ecm problems.