110 mph 25' Donzi
 

Super long thread here...but interesting. So whats the deal with a "pad" bottom? What is the key to keeping a short hull like this safe at 100+ ?

http://www.donzi.net/forums/showthre...h-A-Pad-Bottom

The pad bottom gives the boat a flat running surface to balance the boat on at speed. it also provides stern lift. Steve Stepp put them on the velocities and thats why they ran so fast. see allison boats and other small v-bottom outboards.... Lots of them run over 100. My little Triad V-21 is a pad bottom and runs 100.

fixx
 

a 454 with a pro charger,,110 mph..i call bullchit...
heres the boat in ?
http://cgi.ebay.com/ebaymotors/25-PO...#ht_500wt_1182

I saw that too. The current owner is not the fella that built the boat....i don't think he knows what he has.

110mph 25' Donzi had to be a top notch driver my guess 85-90mph tops!Friend had one 454 pro charger high 70mph on a good day!~

A friend of mine was interested in that Donzi, called the guy and he said it has to be running on racing gas to see 110mph... im not so sure if it would do 110 behind the truck.

I find 110 hard to believe as well, but whoever set that boat up looks like they know what they are doing. Flat trim tabs say that boat is set up to hustle... I bet light on fuel, 1 person and perfect water she nears triple digits....

Maybe 110 is in kilometers. LOL Nice Boat.

Remember that in almost any boat, the last few MPH is all up to the skill of the driver. My grandmother could probably drive my boat up to about 65 MPH and say the boat was topped out. From there to the 76.9 MPH shown on my GPS is all driver.

That said, I kind of doubt a 25' Donzi with a simple Pro-Charger on a 454 is going to run 110 MPH on GPS.

Funny I know a guy with a 18' donzi with the same package and he runs 92 tops.

That's silverback's old boat from Donzi.net. The engine looks the same as it did before, which was a 502. I think he was up to the mid 900 hp area and over 100 MPH

Just pulled engine over winter, but had a 800 HP engine in a 98 22ZX and went 106 on test run and it had more. These hulls are fast, same engine in 25ol= 85mph, I don't doubt his claim.

most people running those speeds with that package will have videos?? Anyone??

I think it could be possible...
 

What size pitch is the prop? How many RPM's is he turning at WOT. I know one thing, if BBlades tuned his prop he is serious about performance.

Video would be nice!

fixx
 

Bob,,the last post i remember is him and hedge hog were trying to hook up and race then i think silver back was blowing smoke up his azz about his engine not being rite and somthing loke the guy that build the engine riped him off and did not put the parts he paid for in the engine..i thought it was a procharged 540 that made the boat go over 100 mph..hedgehog;s 26 did 104 with high boost and somthing like 900 hp..

Really, BBC, Procharger in an 18? Only 92?

sbc/Procharger will run that in an 18 , he got ripped....

fixx
 

ya and he is still running cable over hyd steering lol...RITE!

funny that here is my buddies 21GT with over 700hp and he's running 90 tops. hard to believe a bigger boat is running 20mph faster with maybe 100hp more!! whatever!!

Here's Tom's 20 cig with 800hp running 101mph! in the 2nd video look how the boat sits on the water!! 25 ZX running 110 with same hp??? No way

http://www.youtube.com/watch?v=sLEfsKM0z84

http://www.youtube.com/watch?v=UEbO6tra5to

fixx
 

parnel??? is the boat FAIR WARNING..


then we have geoo with tha x18,procharged 440 cid 800 hp small block doing 115 mph

around 2;10 in the video..
http://www.youtube.com/watch?v=7kg3zoGcrFM

yes Parnell. he's one of my best friends and I even asked him and he said NO WAY! I know a lot of guys are into Donzi but Parn knows quit a bit and knows pretty much every Donzi that goes over 100. that video is badass but until someone shows the gps anyone can say they went that fast on a youtube video.

So a 29' with a mere 600hp going 100mph is definitely out of the question....

Silverback was all about the Roostertail. I tried to talk him out of mounting the drive that high & on a box but where he's from the Roostertail is important. I was going to build that for him, I believe his motor was a Bulldog with good internals, he did swap pistons to lower the compression. David Wade (David Wade Marine) ended up doing the work. once the boat was done he did post pictures of the huge roostertail. He claimed it went over 100, then he only posted on the Donzi.net site once more and we never heard from him again. With the $$$ he spent it should have cracked 100 but we never had any confirmation. other than a pic of a huge rooster tail....:)

GT 21 is not an 18....

LOL, apparently....

Geoo eventually ran what, 129ish?

fixx
 

Cool,,yes we all know him,i personally have not met him in person yet,someday..and yes he is one of the good guys if you know what i mean..i guess he had his hands in many boats including the bigger twin engines but now i guess he prefers the smaller bosts now and i can see where he is coming from..LESS Maintenance lol.
geoo i think when he first put it togrther,wrong prop and such from what i read..GPS speed
http://www.youtube.com/watch?v=XLxxWXk63HI

Geoo also had 1000hp and a arneson

no chit. if someone doesn't know that then go back to kindergarden.

you also are proving my point that a 25' donzi is not running 110 plus. GEOO is running 200 more hp and a arneson with a much smaller and lighter boat and you're telling me a 25 donzi with 800hp with a Imco shorty will run with that??????

I'm still wondering about the 18 with the blown BBC... You threw Parnells boat in the mix, not me...

I have yet to comment on the 25's claim, so please do not ask me to regress to your level, I gradjeeated kindergarden many years ago.. :)

Say hi to Parn for me... Love his 16, one day I do want to snag a ride in the GT...

I know of a 18 with a small block and a whipple making just short of 600 hp that goes 91 but it does not have cable steering.

Don't know of a 25 running 110 though.

Steve's boat is wicked... I thought he was using pulleys and cables to steer it like the old unlimited hydros... ;) ;)

I think Kieth's 25 had a bigger engine than a 454. It is at least a 502 or 540. Hedgehog was at 104 in his ZX and it was bigger ( I think a 26 or 27) with 900 hp. Last Real Texan is around 750-800 on a procharged 502 and is running mid 90's ( I have been in the boat going that fast on a hot, humid day). His boat was also bigger, I think a 28. A 25 is going to be much lighter. The ZX line of boats were not that fast stock as they are heavy and built like tanks. They are tough as nails though.

I beleive Mark Boos built the engine, and maybe the drive. Kieth's build, while aggravating in many ways, was very detailed. More went on than just an engine and drive. It went 100+.

Last note, Parnell's (Sweetcheekz) boats are amazing. I have ridden in his 16 and had a very good look at his GT. Both are amazing, but his GT is my favorite Classic Donzi of all time.

Not trying to be a dik but what's my level? I threw Parns boat in there because I know everything that man has done to that 21' to make it go fast and that 25' maybe has 80hp and I think there is no way that 25' is 20mph faster. Plus I would take Parn's 21' over any 25' no matter what the speed is!!

Parn is one of my closest friends and when I got into boating he took me under his wing and taught me a lot. A lot of people dream they could have the passion he has when it comes to these boats and his 2 Donzis are a work of art. That being said I believe everything he says and if he isn't drinking the koolaid neither am I.

When did GEOOs boat go 120ish? If that's true that is fing awesome!!

LOL, I have no idea what your level is. Hopefully about the same as mine, although my wife would tend to peg me at the jr high level..

My curiosity revolves around the blown BBC 18, not the 25.

AIR, on the 25, he broke 100 with it. Did he hit 110? I have no idea. Heck, I am not convinced that is Keith selling it now, I thought it had already sold once but I can and may be very wrong on that.

As far as Geoo's, I believe his final GPS reading on the boat was like 129 or something. He spent about ten years getting it there, it started life as a stock Volvo outdrive X-18 and slowly and methodically evolved into the beast it was. Family came along, he sold it, but it does live out there still, and one day the new owners will come forward and tell us how it is running now. There are video's on u-tube, you can search em up easily enough.

Parnell's new toy is pretty trick...

Dude, not trying to start anything, but there is alot wrong with what you are saying.

1. You say Parnell's GT is 80hp less than Keith's 25. How exactly do you know? Parnell's GT is a NA boat. Too be honest, as much as I love it, it has no where near the hp the 25 does. No where in the Ebay ad does it say the hp of the 25. The 25's engine is a custom build by Mark Boos. It is not some stock 502 with a Procharger on it. This is a custom one off performance build. Yes, Parnell's engine is cool with the downturned exhaust, dual intake, etc..., but it is around 600 hp at best. The 25 is 900-1000.

2. You are also talking about a stepped hull vs. a very old design not meant to go as fast as Parnell's. Plus, Kieth had his hull blueprinted and alot of other stuff done. Parnell's hull is not near as efficient or meant for the speeds the ZX's modern design is. Plus, Kieth's has a pad bottom.

Look, I am glad you worship the ground Parnell walks on and his GT-21. He is a great guy and his Gt-21, like his 16, are works of art. Comparing a modern 25 zx with 1000 hp to a 30 year old tank like a GT-21 with 600 hp is not very realistic. Bill ran 104 in his ZX with 900 hp. His is 2 ft longer than Kieth's with roughly the same HP. I don't think 105-110 is out of the question for it.

As for GEOO, he went 121+ about 8-10 years ago. The boat was an X-18 called Mighty Mouse and if I remember right, it was a twin turbo sbc "mouse" motor with an Arneson. If you type in Mighty Mouse boat or GEOO into You Tube, there are some videos of it running 120+ on the Conneticut river. The boat is still around in a de-tuned state under new ownership.

Scott, your post showed up before I hit "submit reply".

I am with ya though, I would love to know about a Blown BBC classic 18. I know of a few blown sbc 18's like Steve's and a few NA BBC 18's, but no blown BBC 18's. I doubt a front hanger like Procharger would clear the rear bulkhead and a top mount, like a Whipple, would need a hatch scoop of somekind to clear the hatch. I've seen a BBC in an 18 and it is pretty tight in there.

I am not trying to start anything with you or Scott B but one you're saying "i worship the ground Parnell walks on" and Scott says he won't lower to my level. I haven't criticized either of you but you 2 seem to want to say chit like that. I said Parnell is one of my closest friends and I guess in your little guy world you think that means I worship him. I don't give a fuk about the boats anymore and if you want to make is personal let me know. you don't know me guy.

and i've seen Parnells dyno sheets and his motor made well over 700hp. funny now the 25's motor is 1000hp but in the start of the thread is says 800??

I was under the impression that was Silverback's old boat? Whoever built it spent A LOT of $$$ on that drive combo

My bad on the blown BBC 18'. the one i was talking about is Tyler Logans boat with a 502 and procharger?? I could be wrong about the motor but heard he was running in the low 90's