hull speed

[hemdog]

i just got a 1992 convincor with a bad 454. it has trim tabs and a bravo 1. how fast will this hull go before i have handling problems? and what would you say is the most hp the boat can take? i have a 489 bbc that was from my sanger hydro that i sold. any help would be great, thanks.

 

[keith4216]

Its all about set up. The hull can take as much hp as you can afford but the drive is only good till about 500hp. Hydro steering is a must when getting 70s and above but to see these hulls in the 80s-90s is not uncommon.

 

[hemdog]

keith, i find it hard to believe that a 92 convincor is capable of high 80s, to 90+ mph. the vee bottom SINGLE ENGINE kilo speed record was just broken by brian forehand in his snowy mountian brewery 30' outerlimits vee bottom @100.84 mph. before that the record was 89.672 mph set by steve miklos in his 29' extreme v- bottom. unless i'm missing something here a, checkmate could'nt go that fast or it would be in the record books.

 

[Problem Child]

Keith ( aka Ramrod) is absolutely right about Convincor speeds easily going way beyond 80mph. I know of a few well into the 100-120mph. This has been going on for a long time and im sure these numbers will be getting much faster .

 

[Gimme Fuel]

keith, i find it hard to believe that a 92 convincor is capable of high 80s, to 90+ mph. the vee bottom SINGLE ENGINE kilo speed record was just broken by brian forehand in his snowy mountian brewery 30' outerlimits vee bottom @100.84 mph. before that the record was 89.672 mph set by steve miklos in his 29' extreme v- bottom. unless i'm missing something here a, checkmate could'nt go that fast or it would be in the record books.

Remember, this is a racing class boat with a stock 525efi merc engine and a hull layup so thin you can see light through it. It does take more hp than 525 to make 80-90 mph in a convincor but it is doable. Not as efficient nor as light as what you are talking about here. I am putting a 540 cu in big block (approx 770 hp) in my 97 253 convincor with notch transom and expect to see around 90 mph when setup gets dialed in.

 

[hemdog]

i didnt realize the boats only had 525 hp. like i said maybe i was missing something. so what about chine walking? how do you handle that at those speeds ? my brother had a 16' checkemate with a 150 evinrude ob that was hard to drive, and he then got a 21' enchanter with a 235 evinrude that had some work done to it, he was the only one that could drive it. the chine walking was dangerous. this was back in the late 80's. i'm sure with the deep vee the convincor has, its got to be a problem. how do you set it up?

 

[keith4216]

The larger boats are not as bad as the smaller ones. You'll need to be hitting into the 80s before you see real chine walk on flat water. Hydro steering is a must at 70 plus in my opinion and props will change the ride also. Its a test a tune process.

 

[ezstriper]

keith, i find it hard to believe that a 92 convincor is capable of high 80s, to 90+ mph. the vee bottom SINGLE ENGINE kilo speed record was just broken by brian forehand in his snowy mountian brewery 30' outerlimits vee bottom @100.84 mph. before that the record was 89.672 mph set by steve miklos in his 29' extreme v- bottom. unless i'm missing something here a, checkmate could'nt go that fast or it would be in the record books.

well a few years ago at a radar that is held on the the potomac every year a 251 ran 114, I ran my 251 just over 80 with about 600hp, my 253 with a procharged 509 runs mid 80's....so now you know..