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Unchained
10-20-2001, 09:16 AM
Did anyone read the V-drive tech column in this month Hot Boat? Jim Wilkes made the statement that a stern drive was more efficient than a V-drive. I was surprised to read that, I thought that a stern drive would have the gearcase dragging in the water and be less efficient. I'm ready to buy a second boat, I found a 21'daytona v-drive. It'll be the first v-drive for me. I always had jets and sterndrives before. Then I will be able to bother people on this board as well as the jet board. Might need to wake you guys up first. Any input ?

DANS66STEVENS
10-20-2001, 08:12 PM
Well I have had a pile of boats. I think the V-Drive is by far the best boat I have ever owned. I think if you took two of the same exact boats and ran them one being v-drive and one stern. The V-Drive would be faster. Maybe im wrong but I don't think so. As far as cost to repair thats not worth even talking about. Those stern drives can cost a pile of cash to fix. I have rebuilt two Casales my self and they both work perfect. Try that with a stern drive. Um where did all those little things come from???? I think in looking at the over all picture a V-Drive makes way more sense.

superdave013
10-20-2001, 09:37 PM
They have done side by side test before and the stren drive was faster. But if you're into hp and I know you are a v-drive will take all the power you can sock to it. My buddies go thru a few outdrives a season and they are not stock ones. I see old v-drives all the time that have had big power put to them for years and years. I have never driven a v-drive tunnel but the 3 flats and the v hull that I own now track so well. I will always have a v-drive and rudder under me.

DetroitJim
10-21-2001, 05:35 PM
Unchained, go for the v-drive. That Arias of yours in a 21 Daytona would be awesome. If any stern drive boat is faster than a v-drive, it is due to a more modern hull design and late model power. V-drives are lighter in weight and transmit power more efficiently than any other drive. The power changes direction only once, not twice and not through an inefficient 90 degree helical gearset. Underwater drag is limited to the frontal area of a small strut and rudder. A Casale box can take as much power as you can throw at it, and there is nothing else to break. The only disadvantage may be a lack of positive trim adjustment but proper setup makes this irrelevant. Go for it, the Michigan Hot Boat Association could use another 120 mph boat!
Jim

Unchained
10-22-2001, 04:16 AM
I'm not concidering a stern drive Jim, I was just surprised at the comparison to the vdrive. I had a stern drive in a 27' off shore boat and it worked well but when you had the thing trimmed up and running full speed you could hear gear noise like it was ready to come apart. I read another article in Hot boat where a guy had a blower motor and a stern drive and had to replace two drives a year. I'm not an overall fan of a stern drive, It looks like a repair job waiting to happen.
Has anyone ever used an Arneson drive on a drag boat? Those wicked looking things must be able to take massive HP.

schiada96
10-22-2001, 06:24 AM
I like the strength of a v-drive too but they are just not as efficient did I spell that right. Even the more modern v-drives with the shallow propshaft angle, mine is set at 7 degrees are not as good at pushing a boat as a stern /outboard.
Superdave says it right nothing will handle like a fast v-drive cruser.

GasTurbine
10-22-2001, 06:58 AM
Originally posted by Unchained:
Did anyone read the V-drive tech column in this month Hot Boat? Jim Wilkes made the statement that a stern drive was more efficient than a V-drive. I was surprised to read that, I thought that a stern drive would have the gearcase dragging in the water and be less efficient. I'm ready to buy a second boat, I found a 21'daytona v-drive. It'll be the first v-drive for me. I always had jets and sterndrives before. Then I will be able to bother people on this board as well as the jet board. Might need to wake you guys up first. Any input ?
Yes, I read it, and the reason is trimabillity. You can "trim up" an out drive, thus, able to get a smaller wetted surface, thus, faster. this, of course, cant be done with a v-drive.
Even tho the out drive is less effeciant for power transfer, it can make up for this shortfall by the above.
The thing is, the angle of a v-drive is not effeciant for planning with low hp engines. Because of this acute angle, sheer hp is used to "plane" the hull, by basically "pushing" the whole darn thing up. This is why folks who push a bunch of ponies, usualy opt for a v-drive.
You will also notice that some guys try their best to "straighten" that angle out as mush as possible, but this requires long shafts, and a very forward placement of the v-drive.
Cost and coplexity are another issue, and the outdrive loses on both counts. I know guys who bust these things all the time, and believe me...they aint cheap to fix!
I personally perfere a v-drive. I also like having a "real" rudder too...you will find a v-drive ship will out handle the comprable out drive hands down.

old rigger
10-22-2001, 08:02 AM
Years ago in the mid 50's Bob Patterson had a hemi powered cracker box, "Hot Cinders", that had an adjustable prop shaft. Yeah I know that it's not a v-drive, but it's close. The monkey ( rider, mechanic, the one with the big balls. The one in there for no other reason than just being in there) could crank this shaft to whatever the water conditions dictated. Cranked all the way up it became a surface piercing prop. The prop shaft was longer than stock and extended past the transom. The rudder assembly was set back as well. It was super fast for the day, and set a new record on Salton Sea by over 10mph, ran in the mid 80's I think. It was banned shortly there after.
By the way, I'm not old enough to have witnessed this first hand. I'm old. But not that ****in old!!!!!!!!!!!!!!!!!
[This message has been edited by old rigger (edited October 22, 2001).]

Infomaniac
11-03-2001, 09:42 AM
Unchained:
Conrats on the Daytona find !! I was suprised to read what Jim had written also. There are way too many variables involved to make a statement like that. I have a 19' Cougar v-drive myself. You may have seen it in the October edition of Hot Boat. There is nothing better in my opinion than a tunnel v-drive.
I spoke to Jim while I was installing the engine rail kit in my Cougar. He has built a few 21' v-drive tunnels and had nothing but good to say, especially about the acceleration.
I have taken the engine out of my sterndrive boat and put it in a flat bottom v-drive that I bought. The top speed was identical but the v-drive accelerated much better. Also I could nail it wide open from a dead stop which I would not have even considered doing to my sterndrive.
The comparison made had to be aimed
at larger boats. It is hard to rig a sterndrive in a tunnel boat for optimum performance unless it is at least 21'. Even then it is hard to get the x-dimension correct. The engine has to be way up to get it right.
If we are comparing boats longer that 21' why would anyone want a v-drive installed? (except day cruisers)I do not think we are comparing apples to apples.
I hope Eliminator rigged your boat. It is hard to get it right. The old school guys will tell you the tunnel v-drive combination does not work. I can tell you this is wrong. You will find out this was due to trying to rig a v-drive in a boat from a jet mold. Eliminator and Cougar know how to make it work.
[This message has been edited by Infomaniac (edited November 03, 2001).]

riverdaddee
11-04-2001, 09:19 PM
INFOMANIAC, IN THE MID 80'S I WAS AT BOB CONNELLY'S SHOP TO ASK SOME QUESTIONS AND SAW SEVERAL ELIMINATOR MOJAVES BEING RIGGED V-DRIVES THAT ELIM' WAS CONTRACTING HIM TO THE INSTALLS' ON, SO MAYBE ELIMS' DIDN'T QUIET KNOW HOW TO DO IT CORRECTLY. I had a 20' daytona v-drive but sundown marine's version (alias schida's old 20' they cancelled about 1979) v hull also called a DAYTONA wish I had it back it was a great boat!!! JUST PUTTIN' IN MY 2 CENTS! RIVER DADDEE

superdave013
11-04-2001, 09:50 PM
Hey, I have a 20' Schiada now. Mine's a '78.

e-ticket
11-04-2001, 10:46 PM
I have an 18' tunnel which I picked bare hull a few years ago. It was a drag boat. The name was "HOT FLASH". The boat evidently came out of Riverside Ca. (from the markings on it}. It was set up for a jet drive. Could I really run a v-drive in this boat? I don't know the make of the boat, but have pictures of it. The hull is pretty flexible and quite low profile. Would this be really feasable?

riverdaddee
11-06-2001, 06:34 PM
Super Dave013, 20'er schida great boat, you had said you were at the last v-drive reggatta, you saw my love that I sold while listening to my wife!!!!!!!! it was the only open bow v-drive there. dark red, orange,yellow, and a dark blue pinstripe main hull color white with a blown Pfaff motor. A construction guy by the name of Danny now plays with my old toy, should of never listened to Mama!!!!!!! and remember THERES NO DRIVE LIKE A V-DRIVE!!!!!!!!! later RIVER DADDEE

superdave013
11-06-2001, 06:59 PM
Don't tell me about what you sold. Tell me about what you stepped up to! I don't remember your boat. I'll have to pull out the old hot boat mag and see if it has a pic of it. Mines in the group photo. White, orange& yellow (typ colors for '78) with a turbo engine in it.

Infomaniac
11-06-2001, 08:33 PM
e-ticket:
I guess your 18' tunnel has a center sponson (keel)? It will have if used with a jet drive. One important factor to make a tunnel work with a v-drive is the center sponson cannot be lower than the outer sponsons. They usually are if the hull is designed to load a jet pump. If you mount a strut in this area the boat will get up on the keel and there will not be enough of the outer sponsons working to keep the boat stable. Each design varies so you need to put a straight edge across the last few feet of the boat and check the relationship of these.
If you decide to go for it, they are set up like a flat bottom. plates, pedals and all. I considered building one before buying my Cougar. I was going to have Jimmy Johnson build a Cheyenne (just the hull) buy an old flat bottom and strip all the hardware out.
It was just by chance I found the Cougar. Saved me quite a bit of work. FYI Cougar puts a plug in their mold to change the keel when the boat is going to be a v-drive. They love building them but rarely get a request for them.
Good luck. If you decide to do it I will be glad to send pics or measurements. I am going to attempt to post a pic in this reply.
http://ftp.webzone.net/infomaniac/feb5.jpg
[This message has been edited by Infomaniac (edited November 06, 2001).]

e-ticket
11-06-2001, 09:01 PM
Infomaniac:
Damn, that is one gorgeous ride! Ran out to the garage to check the bottom, center pod is lower than the outside ones. Guess that puts the v-drive out of the question. At least now I won't keep dreaming. Thanks and good luck with the awsome ride.

Unchained
11-07-2001, 06:13 AM
Infomaniac, That boat is a beauty. My jet boat is a Jimmy Johnson Cheyenne. I probably will sell it after I get the 21' Daytona. With your 19' Cougar V-drive can you mat the throttle from a dead stop? . Does it get squirrley ? With my 19' jet tunnel, even with a cavitation reducer I still can't floor it from a dead stop without getting a lot of cavitation.

Infomaniac
11-07-2001, 02:56 PM
e-ticket: Never give up, it just depends on your fiberglass skills and how bad you want it. Checking the bottom was just the first thing I would suggest. It would need to have stringers the length of the boat also.
unchained: Hard to answer that one. There is no dead stop with this one. It has 37% overdrive and a 16 pitch prop. Also alcohol injection idle speed makes the boat go pretty well at idle. I do not throw it in gear from 1,500 RPM idle. I would throw it in gear if I took it to the races. No need to do so for lake racing. No wake zones are impossible and idling close to other boats is tricky. I can nail it wide open from idle speed. It stands up pretty high even with full down pedal. It takes one hop, takes a set and rockets away. It climbs it's bow wake.I think I would overspeed it if I tried to burn the prop. It really needs more gear. I am spinning it 7,700 RPM. That is a bit more than I care to turn it. I do not think I can get more gear in it without machining the water jackets out of the v-drive.

schiada96
11-07-2001, 02:59 PM
Infomainiac what prop are you running?? You can get all the way to 47s in a split case with minor drum sanding and still leaving a lot of wall for the water jacket.
[This message has been edited by schiada96 (edited November 07, 2001).]

Infomaniac
11-07-2001, 06:08 PM
Schiada96: I am running a Menkins 11 1/2 16 2 blade with plenty of rake. Flat bottom prop I think.

Timer
11-08-2001, 08:23 PM
Unchained, I've got one of those boats! I always wanted a v-drive so when I saw this for sale, I had to have it. (I had an Eliminator jet before this one.)