259 Convincor w/ 600hp
 

We have a 2000 259 Convincor w/ a 454 MAG EFI. Great boat, looking to add more power. Anyone running this boat with 600 plus hp? Can you run 600hp in this hull in front of a stock bravo 1?

Re: 259 Convincor w/ 600hp
 

i had a 97 253 with 570 hp. drive lasted 3 seasons. I upgraded to a teague drive and ran it for another 2 years with no problems. boat ran 80 GPS with a 27 Hydro.

Re: 259 Convincor w/ 600hp
 

I am in the process of doing about the same modifications to my '99 259. It had a 454 magnum mpi originally. I just built, dynoed and installed a 540 N/A Carb. motor. It dynoed at 679 h.p. @ 5800 and 661 torque@ 4900. I added a Teague Upper "XR" and Imco lower "XR". I have not yet run the combination, but I have been crunching some #'s. If I can spin a 26" P5X Hydromotive to 5800 rpm, I should get about 87 mph. I ran these #'s with Throttle-Up propellers, they seem to agree. I guess I will find ut in the spring for sure.

Re: 259 Convincor w/ 600hp
 

Vinny,
I hate to rain on your parade, but I think 87mph might be optimistic. I needed 750+HP to see 87mph. If your hull is more efficient maybe, but as I recall you don't have a step.
But, Good Luck.

I might be trying a -2" shorty Bmax with the merc maximus prop to get closer t o 110mph. Ether way we both need to get dialed in. The NYC poker will be here before you know it.

Re: 259 Convincor w/ 600hp
 

Dave,
I thought that was a little high also. These are the #'s that Throttle-Up gave me. If I have the power to spin a 26" P-5X to 5800, it will go 87 mph. The question is... Do I have enough power to do that? I guess we will see come spring.

Re: 259 Convincor w/ 600hp
 

Checkmate454MAG,
Your project sounds great. Just a few questions. Why did you decide to build a 540 carb motor and not rebuild and supercharge your 454 MAG? What will you do with your 454 MAG? Do you have hydraulic steering? How much money does a project like this cost? You stated that you ran 67mph GPS spinning a lab finished 26 Bravo 1. Our best top speed GPS (259 2000 Covincor 454 MAG MPI) is 65mph spinning a Mirage Plus 23. Can you tell me some ride characteristics of the 26 Bravo 1? Do you benefit or suffer hole shot, mid range acceleration? This forum is great.
RJBBC

Re: 259 Convincor w/ 600hp
 

RJBBC,
I was thinking of supercharging my 454 magnum, but decided it was not cost effective enough. I was going to go with a Whipple. But, by the time you add up the cost of the Whipple and the cost of rebuilding the motor to accept a Whipple correctly, it gets real expensive. Then would come my biggest fear. That is, having ECU troubles. Most of us, myself included, don't have the capabilty of mapping out our own fuel curves. Technology wise, for the average boat owner, we are just not there yet. Now I know that Whipple is supposed to be pretty good out of the box, but for me it is just easier with a carb.
The best part is, I still have a complete 454 Magnum sitting in the corner of my garage as a back up.
Yes, I do have full dual ram hydraulic steering and Dana Marine HP-1000 Tabs.
The picture is from this past season, before I changed motors or the drive.

So far to date, this project has cost me $23k, that is including the cost of a Teague Upper, Imco lower "XR" drive, that I picked up used. With the exception of the actual machine work, that number is with me doing ALL the work myself. That number includes the entire fuel system and all other misc. items.
With the Labbed 26" Bravo prop, I noticed a little more time to get on plane, slight mid-range power loss, but more top end. I never hammer it on a hole shot anyway, so I didn't care at all. With this prop, the boat rides high. I believe that a Bravo prop will lift the stern more than your Mirage Plus will.

Re: 259 Convincor w/ 600hp
 

RJJBC . We are running a 99 259 with a Whipple and until now no other mods to the engine. The 454 mag efi has performed very well so far. 280 hours, At 180 the stock outdrive broke a gear. Numbers are 77 on gps at 5100. We have seen a little more light, with a 28 bravo 4 blade. This winter we are putting a set of headers and roller rockers with new heavier springs. Reprogramming of the ECU is done by Whipple. Come spring we hope to see 80 with these mods and 5400 rpm (reset limiter) Hope this helps.

Re: 259 Convincor w/ 600hp
 

I had a '98 253 with a procharged 502. No drive problems for 250 hrs. Easy out of the hole, not too fast on excelleration, and watch your re-entry. She did 78 mph on gps. Would get a little squirly sometimes and you have to pay close attention to waves in the distance, they come up real fast at that speed and pulling back the throttle does not slow down very fast at that speed.

Re: 259 Convincor w/ 600hp
 

lesterloy,
Thank you for the insight. How many hours did you have on the engine when you added the Whipple. Did install the Whipple yourself or did someone else install it for you? I am also curious if any adjustments had to be made with your hydralic engine hatch arm since ours rubs against the stock intake as it is. Did you add hydralic steering? How much did the upgrade cost? Sounds like the Whipple upgrade has proven to be fast and reliable, good stuff.
RJBBC