Power upgrade for 24 IO...
 

I recently bought the 03 24 step with a 6.2 mpi 320 hp. Boat runs great but just a little slow for me= 64mph with 26p bravo. Im probably going to upgrade the power. Considering a 496 mag HO, a whipple charger on the 6.2 or the 400hp scorpion small block. Would love to get 80. Im also concerned with fuel economy Any suggestions???

I am guessing what you want is the 80mph top end with a good ecominical cruising speed (maybe 60 mph @ 3500 rpm or so).

What kind of budget are you working with? If I were you I would probably look at going with a custom engine of about 600hp min to get the 80mph.

I am sure some of the professional engine builders and setup guys will answer in here as well and I would defintely take there advice.

I am not a pro, just using some simple math to get a starting point (i.e. 20 hp=1mph increase so you are at 64mph with 320hp so you would need close to 600hp to get 80).

Also if you already don't have hydraulic steering I would highly reccomend it if your goal is 80mph.

Pretty sure Dave M was touching 80 with a 496HO in his step bottom. Best all around setup I would think

Call Jeff Cropper... He just built up some sbc's(350ci) for an OSO boardmember who has a 28 powerplay.

That would be some great speed for that amount of HP. Like you said it is all in the setup though.

The Superboats are great boats and I wouldn't mind having one as well. A 30 Y2K would be ideal for me with twins.

Not really looking to go the custom route.. I want something on the milder side

if your looking for milder then you could sell your sm block set up and buy a used merc 525 or 500 efi. efi boats get better gas mileage then carbed. or call DEAN GELLNER or TC Tyler both have worked on some high hp sb motors this winter. Deans a master builder and his stuff last a long time, like zul. so what ever direction you go in efi will give better mileage. also a sb turbo motor with efior pro charger set up could be a hot set up you could use your sb motor there too. Dean like Richie Zul just don't build a motor they do extra work to the oiling areas and stuff to make motors last like a few boat builders glass and bolt there deck to hull joints, where others do the norm and glue/bolt there decks and they last a long time too. I like the other. if you need phone # for DEAN I have it. oh a friend had a twin turbo gale banks kit in his 79 24ft SB carbed and thats what sucked for low speeds no wake driving a efi would be the balls for that set up. he had it on a merc 365hp motor made about 600hp it flew from 0 to top end. no sure of top speed it was anywhere from 75 to 80 seemed a 100. he would nail it from 0 to wide open:eek: he had a trs but one day he ate a ujoint. now he is running a 502 with about 570hp doing 74 to 75.trs eats speed. later art

My '98 24 w/496HO ran upper 70's. Saw 80.x once or twice. Best of all, I had awesome cruise speeds.

Take out the 6.2 and sell it. I think a reliable 500 HP BBC would be perfect for the 24. You could run 80+ all day and cruise 55+ in the low 3000's.

500EFI would be a great choice and they can be found for a good price.

Ted-G has a 500efi FS in the swap shop.

http://www.offshoreonly.com/forums/s...p-500-efi.html

thanks dave---how much would you ask for the 6.2---Has about 90 hours runs mint???

Kevin,,The 525 Merc Is Probably The Best Motor They Make Puts Out Between 540/560 On The Dyno,,,I Would Look For One Of Them,,

I agree but they still go for A LOT of coin.

Keep in mind too that hatch clearance is an issue with the 24. Any top mounted blower will require hatch mods. Even a 500/525 w/headers may require mods.

i wish man--im not gonna be the guy with the 25k motor in the 20k boat... Im either gonna whipple the small block or get a 496 HO