23 nova xl top speed
 

I have an 89 23' nova xl with an 330horse 454 what should it be turning for rpm at wot and what should I be seeing for top speed on gps? Thank you in advance!

I think that motor should be propped for 4600 RPM. With a 21P prop, I'd guess low 50's MPH.

I owned a 1988 Wellcraft with the same setup, it ran 56GPS. Light on fuel. Never played with the prop or anything.

Sounds spot on. A Mirage+ 21" would be the prop to try.

Thanks for the info guys I'm runing 56 full of fuel at around 4400 don't remember what prop us on it rite now! I would like to get in to the mid to high 60's is it possible with this hull or should I find somthing else?

Search for Kidnova's posts.
He has a 23 Nova that went low 70's with a ZZ502. He is now over 80mph, but obviously a handful and obviously much more of a motor than a ZZ502.

Yes Kidnova and my 23 Nova ran 80+ I had a 540 730HP and they are a hand full pass 78MPH

Thanks again guys! Gobel nice lookin boat

My .02, Unless you are in love with that boat, I wouldn't spend the time or money trying to make that hull fast. Just enjoy it. If your mission is to go fast, find a more efficient hull.

Goebell what year is your nova and do u have any more pics?

1985...I have tons of pic I bought it as a project boat and total rebuilt it. It was a learning curve for me.

Get out your wallet because once you go down this path there is no return. You will never be satisfied and always want to go faster. Its called the "Speed Bug" and there is no cure.:lolhit:

mine is a project as well i like what you did with yours and had planed on fallowing a similar path.



I already have the speed bug just moving to the water!

I put in over 20K in this boat (call me crazy). I did all the interior, labor and the painting myself. I have never painted in my life. Like I said it was my learning curve.

+1 :evilb:

do you have any idea ware to find replacement stuff for the nova's? basicaly i need a starboard vent window and i would like to find a factory top or at least the support bars.

Just ask here on the forum maybe someone will have some old stuff or a old hull laying around. Can try google it... I needed one also ended up getting some temper glass cut and sealing it in. I got support bars from West Marine also Jamestown distributors has lots of stuff like that for rebuilding.

ok thanks mine is sealed in rite now i wanted to make it operational again. Thanks for your help much apriciated. is there any way you could send me the pics of your build?

Ill have to dig em up. I wont be back to the computer with all my pics of the build for a couple of weeks.

ok thank you very much

Does anybody here have a guess as to what a Nova 23 would run with a 475hp small block? Is that enough hp to spin a 23 mirage on this hull?

I think its going to be very hard to get that kind of power in a marine application out of a small block. It would be easier and cheaper to build a 475 hp BBC. As far as props, don't get hung up on pitch. Its all about getting the correct prop for your power curve.

Well I hear what you are saying, but I dyno'd this engine at 522hp at 6k, that was with dry tube headers though! Maybe I will be closer to the 425-450 range with wet exhaust and all accessories. It's 383cid, with AFR 200cc heads and a host of other top shelf parts. What starting point would you suggest as far as a prop?

you have about 125 more than a stock 330 hp. the 20hp per mph rule of thumb i think is a little low for a hull that small. i would think mid 60's. 70 tops. 23 or 25 pitch. since you only need one prop, try to find some guys to borrow from for test runs. you might find smaller diameter gets better top end. merc laser as opposed to mirage. i saw 50 once or twice with my chris scorpions and chaparral 230xl. all with 260 hp small blocks. both pretty similar to 23 nova hull.

What cam are you running? I have a feeling you used a big automotive cam which will not work in a marine application. The engine must be able to idle under load at 6-800 rpms. The second issue you are going to have is you're going to need to run long tails and really good manifolds. I built a 439 BBC a few years ago and used all top shelf parts along with 10.25 compression and I was 530 hp. The fact that you made the same in a smaller engine with heads that flow nowhere near BBC heads tell me the the dyno was set to dream-o-meter status. Either way let us know what cam your using and some other general specs. Better yet if you can post your dyno sheets that will give us some good info to help you with. I'm by no mean an expert on SB but there are some guys on here that are. Mr. Fixx All has a lot of experience with them as does Uncle Dave.