I have a 2008 Donzi 27 ZR. The boat and motor have about 50 hours on them. Love the boat, but am considering upgrading to more power. I've been reading quite a few threads about this, some in favor of bolt on power upgrades, and some not. I guess I am leaning against bolt on and towards a completely new engine (one that will for sure handle the extra power). I'm just concerned that if one is going to add 100+ hp, upgrading the internals would be a good idea for peace of mind. And when you start doing that, you might as well bump up the horsepower to maybe 600, and then I think you open yourself up to tuning issues, and the cost starts to get up there. So, I'm leaning toward a complete engine.

I also understand I'll need to beef up the rear unit to handle the extra power.

Having said all that, where would be a good place to go to purchase a new (or maybe even low hour) 525 EFI or comparable engine? Any ideas on where I might go to sell my existing low hour 496 HO? I live in Wisconsin, and I don't think there are too many high performance marine engine guys around here. So any advice I could get from you guys would help a lot. Thanks.

I would go with the raylar 525 kit....when its all said and done you will save money over upgrading to a merc 525...alot of those used 525s are abused and you might find yourself sinking more money into the project after you spend 15 k on a used one.

Offshore performance specialty in fort myers fla.
( Don Carter sr. ) they have new motors in crates
every size .

The 496 needs forged internals......and dont let anyone tell you otherwise!! Price out the forged rotating assembly and Raylar kit, probably 10k +/- some.
You could probably sell your 496 for around 7k +/- some.
Price in the labour to tear down and reassemble the motor and where do you sit price wise???
Now you are not far off the price point on low hour 525......got ya thinking now eh??
Anyway, if you are not in a rush or you have the funds there is lots to think about.

yeap... +1

pm me with the price you are looking to get for your 496 if it is a ho!!!!!!!!!

The place to buy and sell used is right here on OSO.

Used low hour 525EFI's are going for about 20k. Used 496HO's are in the 8-9k range.

Go with the 525 EFI for sure and don't look back! I got a 2007 vintage one here with about 40 hours two years ago for $20,000. I sold my 496 to a guy in Germany. Had to crate it and take it to the shipping company near Detroit Metro Airport. I had to have my exhaust tips relocated and purchase new tails to keep the Q&Q. I also beefed up the hull. I also promptly grenaded the stock Bravo 1X upper. Other than the exhaust and switching to analog gauges the swap was a bolt in. Don't waste any money on the 496. My boat is a 2005 22' Donzi Classic. I'll dig up the link to my project.

This documents my swap. It got off topic somewhat and raided by the steering popos (Zeiger steering is on now) and a former moderator took some posts with him when he left the site but you may find it helpful if you sift through it.: http://www.donzi.net/forums/showthread.php?t=57025

Yikes, I just re-read that thread. And I thought things got out of control HERE sometimes. At the least it is an entertaining read and if you just read my posts you will see how I did the swap. Good luck. I hope you do it.

Check w/ Mel Riggs, he is in WI.
Also, El indio on this board is now owner of a large Merc dealership in WI.

+1 for swapping to a 525,,,,, although the Raylar kit is nice.

It will be alot easier to get rid of when resale time comes around

Stock power always sells faster