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MIAMI DAVE GOES 117 IN HIS PRO COMP!

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Dave (H20perf) just called to say he just made a pass @ 117 on GPS!!

He did it in his 4 seat Pro Comp with his home brewed 3.0 JohnRude running stock carbs, 130 lbs compression and on pump gas!

30" X 8500!

Congrats Dave, that rocks!

We both know there's plenty more there if you want it ;)

Gary

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Thanks guys,I really want to get to one of thes events but it allways seems like im working.Im trying to change jobs for a better schedule,Actually was taking a 4hr test at FPL on sat or i would have went to the alva deal.Thanks again for the GPS gary should have bought one along time ago,As much as i've run this boat i had more fun today playin the gps. Dave

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Yes its a sportmaster.Its impossible to keep the epoxy filler on a stock case with a nose cone from peeling due to corrosion when u run alot in salt.Dave

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Yes its a sportmaster.Its impossible to keep the epoxy filler on a stock case with a nose cone from peeling due to corrosion when u run alot in salt.Dave

What does it take to put a sporty on an OMC? I've got an F1 mid, if that makes it any easier.

IPB Image

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I will make it real easy for ya, lets trade mids. :D .The adapter plate isnt that hard to fab i made mine myself.Take a plate large enough to cover both bolt patterns, mine is made from 5/8 thick 6061t6 ive seen 1/2 used but personally i think its abit thin.First drill A 7/8 hole in the plates center line, drop the plate over the drive shaft and pick up the bolt pattern from the omc unit then do the same for the merc (this works nice because both units use the same dia shaft) , now u have both bolt patterns (omc/merc) with the drive shaft centered on them.Now u can cut out the areas for the water pump,exaust and use the outside contour of the larger housing(omc).First u bolt the adapter to the sporty then bolt the assembly to the mid.Dave

OOps didnt read the previous post. Uh I mean the adapter plates must be made of unobtanium and the one i have is the last one that NASA made before they used the rest of the material on the scram jet engines.Take over gary.Dave

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Damnit Dave!!! Can't take you anywhere!

Keith is correct too.

You have to make/fab linkage to convert the OMC's push/pull to Mercs rotate for the shift linkage.

Since Dave is giving away all our trade secrets anyhow.......... send him a block of unobtanium and a chissel and he'll make you one ;)

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I know where you can get one of these mids, they just cost out the wazoo. Kingfisher has a couple last I heard. But, I wanted to get a 6" from him, just didn't want it bad enough to pay over 4 GRAND!

The adapter doesn't look too hard to do. It already has an adapter to run the V6 case so I might be able to just add some holes and do the shift linkage. I can't believe the driveshaft splines are the same?

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I know where you can get one of these mids, they just cost out the wazoo. Kingfisher has a couple last I heard. But, I wanted to get a 6" from him, just didn't want it bad enough to pay over 4 GRAND!

The adapter doesn't look too hard to do. It already has an adapter to run the V6 case so I might be able to just add some holes and do the shift linkage. I can't believe the driveshaft splines are the same?

Knew about the stuff they had for the big $$$$$$. I'll build one first.

Not sure the splines are the same on the drive shaft?? Dave......?

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Splines are not the same u have to weld the end of an omc on the end of the merc shaft,only the diameter is the same.You can use all the merc shift linkage and make it work by bolting the merc slider on to the intake of the omc with an angle.Dave

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Splines are not the same u have to weld the end of an omc on the end of the merc shaft,only the diameter is the same.You can use all the merc shift linkage and make it work by bolting the merc slider on to the intake of the omc with an angle.Dave

You mean like this ;)

not sure where this spy photo came from :o

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I wouldn't say it looks exactly easy, but it looks nowhere near as hard as I thought it would be. Yea, 4k is crazy. Wayne Taylor builds them for under 2K.

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When you see Daves conversion job in person it looks pretty simple after seeing it all togther.

The L/U is the ultimate weak link in getting a JohnRude to a "Warp Speed" level.

The stock Johnny case doesn't have near enough skeg in the water to keep it tracking straight at speed.

They came out with the "Lightning" case which is much better (has a Sporty style skeg) but I don't know and have'nt seen anyone try to go really fast with one.

PLussssssss, it doesn't have a freagin low water pick up :o

Duh!

They have a new "Magnum XP" which has been on the drawing board for a year now and I am told it has low water p/u built in to the nose as an option which is kinda cool.

I also heard though that the gears/internals are bigger to handle more power and made the freagin bullet an additional 1/2" larger diameter!

Still waiting to learn more about this one.

If we are surfacing the case anyhow and carrying more weight on it.........what will the ultimate effect be??

I am struggling with the above right now???????

I am kinda leaning towards a Lightning w/a cone at this point for two reasons. #1. no "Merc pts on a Johnny" crap. #2. I have parts and tools, and know how to build Johhny l/u's.

We'll see.

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Het Dave, what are you running for ignition? I'm running a Yami setup, but for some reason I'm having a hard time getting to turn like yours. I've seen 8600 a couple of times, but it really doesn't like to rev more than 81-8200.

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Het Dave, what are you running for ignition? I'm running a Yami setup, but for some reason I'm having a hard time getting to turn like yours. I've seen 8600 a couple of times, but it really doesn't like to rev more than 81-8200.

86 Twin pack system (8500L)with vented second effort flywheel,I was having troulble too until i made up a 4 coil stator.The extra volts helped alot, i now have about 350 peak volts to the packs. What kinda compression does that motor have?EX port height?

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I wanted to put my 86 XP no limiter twin pack system on with a gold flywheel but I was overruled by my builder and got the Yami. I think the porting is about 1.5 and over 200 compression with 32cc heads. The nice thing about taking that much off the heads is you can use the -809's and don't have to look for -490's (even though I have a few sets). I like your stator setup. We had a custom Rapiar single pack setup, but it played hell firing at startup. Had to go 24v to the starter. My twin pack setup is brand new and Spanky won't use it on the race motor. I'm going to have to have him build me a hot play motor out of all of the extra stuff I have.

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Wow porting is way up there along with the comp,I would think u would be out turning mine easy.I would love to run my comp up there and see what it would do,but cant afford the gas.I usually burn 30 gals up every trip think that the fuel bill would take all the fun out of it.I have some removable chamber heads but havent put them on it yet seems to run too good as it is im afraid ill puke it if i mess with it anymore.Dave

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I think half of the problem I'm having turning revs is the cowling. When Jack Barsch built this cowl I didn't tell him no vents in the front. So, it draws a ton of air in the front and I think it's interfering with my airflow. I'm going to cover it tonight when I pull the heads to check it out. I'll let youknow how the insides look here shortly I hope. I'll take a pic of the cowl so you can see what I mean.

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Well hopefully Im not too far behind you guys in the near future. I have the new sporty with titus mod., and a gold light wieght flywheel with twin 8500 limit packs to install, just waiting on the short mid, and the jack plate to make it all fit. This is lots of part and pieces and cash, but should be all worth it in the end.

What it the weak link in the omc ignition system ?, and why switch to Yamaha ? Also whats the stock ex port hieght ? 1.70 ?

lets keep this post rolling, great info.

Thanks

Lance

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Sounds like u have most of the stuff to make it scream.The ports are 1.7 on the open deck blocks but the later closed are 1.8.The omc ignition will work fine to 8500 u just have to have all good parts.I would go with msd before i put yamaha on.The gold wheel magnets dont seen to be as strong as in standard flywheels thats why i whent with the 4 coil stator.dave

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Sounds like u have most of the stuff to make it scream.The ports are 1.7 on the open deck blocks but the later closed are 1.8.The omc ignition will work fine to 8500 u just have to have all good parts.I would go with msd before i put yamaha on.The gold wheel magnets dont seen to be as strong as in standard flywheels thats why i whent with the 4 coil stator.dave

Ah Grasshopper, we disagree here. The Yami ignition is preferred by a couple of drag racers I know, and I use it too. 2 of them have had an MSD system and went to Yamaha. I've seen it turn 9200 no problem. Much simpler, much cheaper, and much easier to install. You can use a stock starter too.

BTW, I found where my revs went and it wasn't the cowl. Look for an update on this one soon. And my jetting is still pretty far off. I just drilled the idles to 67 (they were at 42), the mids are still at 14. I think I'm going to have to drill the idles more, and meaybe lean the mids a little too. The mains are gonna stay where they are for a while.

I spent a lot of time talking to Wayne Taylor at the Wetumpka race. The Madman gave me some great advice on boat setup, he really helped with the way I launch the boat. He tossed out a few more tips I'm gonna work on also. I may go out this afternoon and do a speed run. If not I'm going to on Saturday. Gonna try and turn the 32 to at least 117!

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Ah Grasshopper, we disagree here. The Yami ignition is preferred by a couple of drag racers I know, and I use it too. 2 of them have had an MSD system and went to Yamaha. I've seen it turn 9200 no problem. Much simpler, much cheaper, and much easier to install. You can use a stock starter too.

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