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Pro Comp 260 2.5
07-11-2001, 11:21 PM
Hey Anthony, I happen to own an STV Pro Comp (94) with a 2.5 260 (93) since 1994, when I picked up my boat from STV in Tennessee they forgot to drill the holes in the transom they told me to drill them @2 1/4 inches from the top of the transom, I drilled them @ 2 inches mounted the motor in the third hole, no jack plate. I have ran the boat up to 124 mph on radar (stalker) & GPS with a 14-32 cleaver @8700 rpm on a stock CLE, with the trim set at that speed the point of the bullet is 1 inch above the bottom. If your looking for top end this might be your best height, it works for my boat. Fred

AnthonySS
07-12-2001, 09:13 AM
THANKS FRED,

It seems that most agree that 1" to 1 3/8" is the range to use. That is an aweful fast STV you got! Thanks for your input and I would love to hear more about your Boat,

Sincerely,

AnthonySS

Pro Comp 260 2.5
07-12-2001, 10:55 PM
Originally posted by AnthonySS
THANKS FRED,

It seems that most agree that 1" to 1 3/8" is the range to use. That is an aweful fast STV you got! Thanks for your input and I would love to hear more about your Boat,

Sincerely,

AnthonySS Thanks Anthony, I know its hard to believe it has gone those numbers because the only things I have added to the motor are a front spacer behind the stock air horn, I shaved the heads to 31cc and had Diamond Marine build me one of there tuners. I am still running an analog A17 brain and it has a 20 inch bass mid section (no offshore snout) stock flywheel and NO porting has been done to the block. I just installed a bobs gearcase trying to pick up at least 1 mph but so far due to heat and humidity here in Florida I have only had it to 121.4, the 124 was done in December it was 65 degree that day, maybe with some good air I see that 125 # I have been looking for. The boat has full interior, carpet and a stereo w/4 speakers it weighs 1400lbs w/no driver. I have two other friends with STVs, one has a river rocket w/an S3000 that ran 132.4 on radar and the other one has an 1989 center steer with a 15inch 2.5 Diamond motor and he is running a SM gearcase flush on transom no jack plate and its gone 130mph, there boats are really flying. Fred

AnthonySS
07-13-2001, 09:16 AM
Dear FRED,

I can easily believe this. I too have seen what these boats are capable with the right set-up. I have heard that you Florida guys are probabbly the fastest Tunnel Bunch around. We have a few up here in Canada that are playing in the 120's with STV's too!

100 is fast enuff for me!

Sincerely,

AnthonySS

Firestarter
07-13-2001, 09:33 AM
Those speeds don't supprise me at all.
My (now sold Triad STV river rocket)ran in the low 120's with a mod 260, but on pump gas. Blake S is the fastest around right now, he is running 126 everyday with a stock S3000, with a set of 36cc heads, SVS and a mildly worked sportmaster. ( I should add that he is hard on the rev limiter.)
But the fastest STV around period is a fellow from the Ottawa area that had one of Speedmasters old Mod-vp racers with a 260/nitrox/speedmaster #4-----for a grand total of 138mph. That boat has since been parted out but, I have never heard of anyone coming close.

RT

Pro Comp 260 2.5
07-13-2001, 10:36 PM
RT, (Firewalker) Im glad to here about those boats running those speeds, I get tired of hearing all those guys telling me that my motor has all kinds of work done to it that Im not talking about, even running 93 pump gas they still dont believe. I forget to mention the guy with the river rocket ran 132.4 with an xr6 1.78 stock gear 150hp gearcase and a 14.5x30 lab cleaver at 9000rpm, I never heard of someone running a speedmaster on an S.T.V., I allways thought the prop would be to small to keep the hull in the water at those speeds but if he did it he's a bad ass. 138mph is going to be real hard to beat. The guy with (89) center steer used to drive Indy cars at 220mph and he is the only one with enough nerve and motor that might try to go that fast with a speedmaster, but I think he's happy running 130 every time he makes a pass. Thanks for the info, Fred. By the way Anthony, there are a lot guys down here in Florida that put 26inch props on there boats and only run up to 100 then they let off, thats as fast as they want to go.

WaterBoy
07-13-2001, 10:53 PM
Where in Florida are you talking about. I live in Southeast AL. on the Florida line.

Thanks, Waterboy

Pro Comp 260 2.5
07-14-2001, 10:20 PM
We are way down South in Fort Lauderdale, we run along side a highway called Sawgrass, it's right next to the Everglades, but we got friends with tunnel boats, Allison's, and Action Marine's from Ft Meyers, Clearwater, Tampa, and the St. Pete area who get together every once in a while to do some radar running. Our last big meet was in Palatka on May 12&13 a lot of boats showed up from every where, one STV came down from New York. Thanks for asking Waterboy. Fred

Firestarter
07-16-2001, 09:43 AM
Ah the mistical 130, that we have yet to reach. And 130 out every time is huge. We can break 120 every outing, but finding enough cool air and calm water is tough till the fall.
To go that fast, we are running 14.5 X 30 cleaver, 1.75 gears in a modified sportmaster at 9000 rpm.
The powerhead has since gone to jay smith for a freshen and a little power boost (still pump gas), and an A-10 box to get the revs up 9500 limit.
As for the speedmaster, it must work well, once you are rolling most of the lift is aerodynamic anyway. He ran a 10.5 X 21 three blade---that is about all I know. what I do know it that Dave Steckbauer can re-shim a speedmaster to turn std rotation, so you can swap back and forth between cases, then you can run a merc inboard hydro prop, which have larger diamiters.
I would also like to point out that, we are going that fast with full weight, 4 seat river rockets, with un-blueprinted bottoms. STV's are the fastest boats around...I have never seen anything to prove to me that anything comes close. (yes their are better drag boats).
Next time you have a Fla. get together, give me the heads up I will make the trec.

RT

STV Tunnel
07-16-2001, 10:24 AM
I have said this on here before and I don't know if everyone believes it, but my STV LTV has run 103 mph gps on a stock 2.5 efi 175 with no more than a tuner, nose cone, reed work, 28 RE 3, bullet splitting the pad at 95% up trim, and 2.5 inches of added setback at 7000 revs. PLUS I get unbelievable gas mileage and turnkey reliability. I have since lost some revs or prop tuning, but still can hit 95 under most conditions daily.

Pro Comp 260 2.5
07-16-2001, 11:07 PM
You don't have to convince me (STV Tunnel) I believe your LTV can run that fast. We actually have a friend down here with a 16ft Action Marine that has a slightly modified 2.5 15 inch mid and a XR6 1.78 that turned a 28 chopper modified (lightning copy) at 9350rpm on the recall tach and ran 122mph on GPS and RADAR, this boats speed no one believe's. By the way Firewalker what compression does your motor have to let you run those speeds on pump gas? Sounds like you might get that mistical 130 with a Steckbauer 1.75 XR6 due to the smaller 4 1/4 housing over the bigger SM case, our friend with the River Rocket ran his 132 with a XR6 1.78 and your same 14.5x30 cleaver at 9000rpm, I don't know what % slip you have but his is only 8%. We actually have a little get together this weekend at the Peace River but I know it's to short of notice for you to make this one, I'll let you know how we all ran and when the next get together will be with plenty of notice. Thanks, Fred.

Firestarter
07-17-2001, 08:09 AM
ProComp 260, I have heard of that Action, Word has made it all the way up hear to Canada.
As for compression, it is only 140lbs (36cc), I understand that the XR6 is good for 4+mph but it is not durable enough to give us what we need.
As for slip we are in the 13% range, but when we move over to the prop that we run for everyday running (26ET) slip drops to 6-7%.

RT

Let me know when the next gathering is.

Pro Comp 260 2.5
07-17-2001, 11:34 PM
Thats great to run those speeds with only 140lbs, you guys probably get good air up there alot more than we do down here. This little orange Action does run, you should see how hard it accelerates and gets to 122 but he has to get out of it cause she starts lifting fast. He runs out of nerve, or it might just pick up a two or three more, he knows the hulls way overpowered. By the way I got 150lbs of comp. so I'm getting away with pump gas to, It's pissing off alot of guys who have to spend that $5 & $6 bucks a gallon for race gas. Dont feel bad my slip with my 14x32 is 12%. I'll keep you posted on the next big gathering, Thanks. Fred.

STV Tunnel
07-18-2001, 12:50 AM
hehe....125 lbs cylinder pressure here...guess I could run 87 octane regular if I had to and still go 93 without blowin up ;-) All I can say is I wished the guys would have drilled the motor holes that little fraction higher on mine (I would have) so I didn't even need a jackplate. You could drive the boat much harder safely without it. Setup accounted for 40+ miles an hour on this rig. Without endless configuring this boat would have been nothing. I always thought that no jack plate and bullet splitting the pad would have been the fastest combination, but never redrilled the transom to find out.





All in all, this boat isn't the fastest, but it is the best damn all around trailer boat in the world as far as I am concerned. It is light and easy to tow, easy to store, and easy to maintain. It has the v hull for what it is good for, the tunnel and MOD VP features that it has, for what they are good for, allot of room, and I mean ALLOT, and storage for what kind of hull it is, AND the best thing is no drag motor economy, engine wear, and failure problems to deal with. I even kept the 40 amp system. I am sure with a bigger wheel than the 28 I could get higher into the low hundreds. What a great boat Summerford built.

AnthonySS
07-18-2001, 08:12 AM
Dear STVcrowd,

The one time that I had a GPS available, my Speedo , my tach, and slip calculator at the same time, I also calculated 12% Slip.

The GPS read 96, the Speedo… 97.5, the Tach… 6900.

Using a Bob’s “Alli Mod” Drive, with 1:87 Gear Ratio, and 14.5” x 30” Cleaver, P/S C/L at ˝” above the pad, being pushed by my little MPP 2.4 EFI (240 hp).

This was with two on-board and was on the first day out for the season, so I was real pleased!

Later that day, as I got reacquainted with the boat, I was pulling 7300 RPM, once again, with 2 aboard, sitting in the front, with 12% slip gave us about 101…again I was real happy!

Few people realize that a Cleaver is designed to do just that…SLIP MORE! This is due to its low rake and blade design, which enables good acceleration, and lets the motor wind up more! This probably also is why they handle so nice too, a low rake blade “Piercing” the water instead of hi-rake blades “Slapping” the water!

…So more-slip is favorable with Cleaver props.

Sincerely,

Anthony SS.

Pro Comp 260 2.5
07-18-2001, 10:03 PM
STV Tunnel if I read it right and your running a jack plate you might want to try removing it, if you remember old R. Summerford designed them to run without one. All three of our STV'S running in the 120's & 130's have no jack plates, motor's mounted in third hole. Both boats running 130 never redrilled there holes, so you might not have to.



Hey Anthony I think you might have less than 12% if your GPS read 96, at 6900 with a 30pitch your speed W/12% should be 92-93, at 8% it's 96 you might want to check your tach, even at 7300 your speed was 101, on the calculator formula W/8% I get 102mph. Believe the GPS, we used the Garmin 12 & the Garmin III plus checked them both against a Stalker-Pro radar and there dead on the money. Fred.