2 years done

[craigdskilling]

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[craigdskilling]

I thought this would be fun if guys put there boats up and see what we think there worth.So I have a 350 mpi with a whipple charger pushing 550 hp and a Blackhawk drive.Cant tell you top speed, do to I have not run it yet ,what do you guys think it will do. New cam new pistons new everything everthing had to be custom. Also a galvanized duel axel trailer built for a 22 but made for 18 for now,that also has new tires bearings bunks. Now I'm not selling this is for just for fun and your input.Please let's see what people have thanks craig

[craigdskilling]

Attachment 81481Attachment 81482Attachment 81483The swim platform is gone and the boat is a 1984 classic.

[Ed Donnelly]

If it was for sale, this is the perfect time for our south of the border guys
When it is minus 20 outside I would say $18,000 ..Ed

[yeller]

Nice setup! SBC, Whipple, 550hp, BH drive.
I love the whipples. Way cleaner setup than the Procharger.
What speed were you getting with the old motor and BH?
I'm assuming you have 31" props and you left the X dimension stock?

My 22 with 550hp did 86gps first time out with the BH. Never really got a chance to gps it again, so don't know if I could have got more.
Tabs1.jpg Engine1.jpg

Soooo.....how much more speed can an 18 get with the same hp/drive? A stab in the dark.....I'm going to say 93mph.

You'll be max'ing those props out with your hp. You could probably go up an inch, but I'm sure you know how much that would cost.

I have an extra 100hp now, but won't be able to use it because I'm limited by the props. Sure don't want to spend $5k + for custom props. I've been thinking about changing the gear ratio to 1:36 to take advantage of the extra hp...............but then, I should probably get the thing running 1st. I've already been down 4yrs



I'm going to stay clear of valueing someone else's boat. I know mine is worth a whole lot less than I have into it.

[craigdskilling]

My old set up I was pushing 375 to 400 hp and I was running 27" props and that old heavy swim platform and I was running 75mlp, I tried with my 31" but not enough power to turn them,So I sold the old motor for good $$ and started this journey just so I can spin those damn 31".
Yeller your right on the money with y is fast never fast enough.
My drive 1:50 ratio and the the drive is sitting at 17" to center not quite the magic spot but works well.I had the chance to raise it at the time but, I would have to make the hatch even higher and then new motor mounts and goes on and on.I beefed up the stringers and the transom is all new I told the guy to build the hull for 100mlp so that was all done for that.the scoop has a hole cut out under it for air flow.The stainless marine exhaust was specially made to be higher rise and the water will mix at the transom it will almost be like a dry exhaust.I put slip in exhaust silencer in for the police,guy's I have no idea how this thing will sound like cant wait.
Speed I'm hoping to be in the 90's do you think ill be there

[MDonziM]

I'll toss a 92mph guess out there. depends on the x-dim imo. My BH is set at the standard bravo height and with 600-625hp ive only seen 86 mph best but the boat doesn't feel broken loose. I think if my x was up 2-3" it would be 90mph.

Yeller, curious why you mounted your tabs flat...? FYI the 20' cig/bh guys around here used to toast their drives with 1.35 gears, but then they had 80o-850 hp. You have 31" props? I only turn them to 5000 rpm or so.

[yeller]

Speed I'm hoping to be in the 90's do you think ill be there

I'd be shocked if you didn't easily pass 90.

I'll toss a 92mph guess out there. depends on the x-dim imo. My BH is set at the standard bravo height and with 600-625hp ive only seen 86 mph best but the boat doesn't feel broken loose. I think if my x was up 2-3" it would be 90mph.

Couple of things. Are you sure your over 600hp? Maybe you're only about 550~575. That would put you at pretty much the same as mine. Other thing is, mine is an 2004 and I believe the older boats are heavier, which might explain why your speed is the same (with more hp). I'm only guessing my old motor was about 550hp. I based that on the Procharger being good for about 125hp on a 496HO and the fact that CarlC is doing low to mid 80's with a 525 and shorty. I figured I had roughly the same hp as Carl, and the BH gave me a few more mph over the shorty. Maybe I'm wrong and the old motor was making more hp than I thought and I won't gain anything with the new one. Hopefully we'll know this spring.

Yeller, curious why you mounted your tabs flat...? FYI the 20' cig/bh guys around here used to toast their drives with 1.35 gears, but then they had 80o-850 hp. You have 31" props? I only turn them to 5000 rpm or so.

I am concerned about the 1:36 gears adding more stress to the drive, that's why I'm only thinking about it right now. For now, I just want to get it running right.
I put my thoughts on tab position in this thread: http://www.donzi.net/forums/showthre...Plane-Mounting

[MDonziM]

I don't know about weight/layup, I was thinking you have a higher X which would definitely help. You're running 31" props right?

Never had my motor dyno'ed but its supposed to be 625-650hp by specs so I say 600 should be conservative.

[craigdskilling]

Im not sure if you r talking to me or yeller,but I had mine dyno at 550hp and yes I think my x is a little higher than norm the charger fits very high under the hatch if you look at one of the side shots you see how high that's y had to cut the hatch, also did you guys see that I had to put two of the donzi hatch closers on either side.How much hp can the blackhawks take.thanks craig

[MDonziM]

Craig- was responding to Yeller from his previous post.

I have seen 2 20' BH Cigs with 750- 800hp but they did break the drives. Like any bravo, durability is determined mostly by throttle response re-entering the water. For me , the bh is great for stability at high speed and most conditions that I want to be out in, but it is limited in rougher water.

- Marshall

[yeller]

I don't know about weight/layup, I was thinking you have a higher X which would definitely help. You're running 31" props right?

Yes, I have 31's. My X is at the stock position. Don't know if Donzi changed it over the years, so can't say if it's higher than yours.

...also did you guys see that I had to put two of the donzi hatch closers on either side.How much hp can the blackhawks take.thanks craig

I did notice the 2 latches. Were you not comfortable with just the one?

As far as the BH and HP, it's rated about the same as a Bravo.....so you're already over the claimed acceptable power. There are a lot of people running our hp with a Bravo and they are holding out. Of course there are those that break, but there are also those that break with a lot less hp. Like MDonziM said, you just have to careful about airing it out....and don't hammer the throttle.

My cousin has a bit over 600hp in his 22' Cougar Offshore and he has well in excess of 2000 hours on the Bravo and it's never been apart. He even twisted the prop shaft at about 500hrs, but it's still going strong.

[MDonziM]

Yeller - pretty sure around 99'/2000' they went up 2" on the x-dim. It might have been around the same time they changed the stringer width for the 496 vs 502 motors, not sure.

[craigdskilling]

Had to put two on because of the supercharger front lined perfect with the old tie down,also had notch it there for the pulley.

[yeller]

Yeller - pretty sure around 99'/2000' they went up 2" on the x-dim. It might have been around the same time they changed the stringer width for the 496 vs 502 motors, not sure.

I was unaware of that. 2" would definately make a difference, especially with the BH.