SO Yamato Rule Changes

[Tim Weber]

John,

I think you may have something with the shorter staight away. Another thought is a shorter starting chute.

We all know a good 102 will out fast a 302 in a long straight line. The last 2 nationals, specifically Dayton had about a 1 mile long run to the clock if you wanted to go way back to the far side of the lake. I've seen Worm do this for years with his CSR of which the last 2 years he's dusted us with a 102. When I asked him about switching from his 302 he said it a good mile faster.

If the starting chute was shorter, 102's could not build up as much speed and the superior torque of the 302 would show. Think about this, how many courses do we run with a nationals lay out? Think about places you have raced on with shorter chutes. A few that come to mind are, Burlington, Oshkosh, Depue, Jesup, Rochelle,Camden and Alexandria. What I am getting at is we really don't run too many nationals type courses during the season.
Why are we running a different type of course a couple times a year? In my opinion, a Dayton is not really representative of what we do week in and week out.

Tim

[dholt]

Let's get some facts straight...

First of all, 20ssH is the second largest stock class. Participation totals:

2000- ASH 100
20ssH 106

2001- ASH 94
20ssH 104

2002- ASH 103
20ssH 115

2003- ASH 105
20ssH 107

2004- ASH 107
20ssH 111

2005- ASH 97
20ssH 121

And I collected the numbers on 2006 a week ago...20ssH still larger than ASH.

I point this out because this is a prime example of NOT examining facts before speaking. This website is a breeding ground for that.

Another fact: NO 302 has ever won the CSH Nationals. And we're not racing on 1 2/3 courses. Nationals courses are bigger than most weekend courses, but not by a ton. The 302 can't run as high...so will not have the top end to win.

And for those proposing shortening the 1500' run to the first turn to 1000'....ask yourselves why that rule was put in place to begin with. Must be a good reason.

Final fact: The height rule on CSH and 20ssH had nothing to do with safety. It was enacted because guys were working all kinds of magic on their gearcases (shaving top of case) and were running really high...thus going faster...without getting DQ'd because of faulty spec rules on the gearcase.

[DougMc]

the 1500' run to the first turn to 1000'

Where does the 1,500 begin and end? Is it from the 2nd turn's last pin to the first turn's first pin? I have never paid too much attention, I guess I should in the future.

[Matt Dagostino]

Longer runs to the first turn

should be the goal if safety is really a concern!! Dana is right in his point about the length of the run to the first turn at a National Championship. The 1500 foot rule is a safety measure so boats can somewhat spread out by the entry of the first turn. I always wondered why a rule isn't in place to possibly make a 1000 foot run to the first turn mandatory at 'local' races!! I know this would perhaps be impractical at many sites but at places like Whitney Point etc etc it 'sucks' to see short runs to the first turn set up when so much water is available to lenghten the run to the first turn.

Our last event at Millville has a run of less than five seconds to the first turn and lends itself to 'first turn' incidents and gun jumping. I would hate to see our National Championship event course minimized for the sake of helping certain motors be competitive.........

Doug, the 1500 foot distance is measured from the starting line to the entry pin of the first turn! Of course it is only mandated at our Summer National Championship Gala!!

Later

[drbyrne55]

Shaving?

Before 1/2 depth rule, was shaving the gear case legal? It either was or was not. I would think since this is a STOCK class, this would be illegal. So, make shaving gear cases illegal. Can't inspectors catch this just like all the other tolerances they check? Why not change/clarify the faulty spec rules if this is the case?

Why make a 1/2 rule if there is a guy who can run at "0" and he is keeping his engine stock/ and not shaving?

Just a newbie looking for answers.....
Thanks,
dan

[14-H]

***.

I knew that if I was wrong about ASH being the second largest class it would be 3-S that pointed it out.

This business of carving on the gearcase should be put under control. Holt is right: that was the reason for the height restriction in the first place. It is still a problem and it is also a problem that the 102 is faster at the nationals than a 302.

But, that's just my opinion. Ed

Add: Dana: very well put! Nothing but the facts. Ed.

[dholt]

For the newbies...the 1500' rule is the measurement from the starting line to the entrance pin of the first turn at the Nationals.

Secondly, the Yamato gearcases do have several measurements on them...there are specs to prevent all out shaving/shaping. Radious at the nose, thickness, skeg, etc... But there was no rule on height of the case...from the bottom of skeg to the top of the case where it bolts onto the towerhousing. Shave the top of case...now your prop shaft is higher.

Once you get contours done right...isn't much play room to tinker. You'll get busted. I can't recall the last time a Yamato got tossed for a gearcase at the Nationals.

Ed's opinion is proven by fact. No 302 has won the CSH Nationals...where the fastest 102's come out to play.

Pretty discouraging to watch guys with 302's beating their brains out fighting that battle. I empathize with them. Of course, I'd have bought a 102 instead.

[mercguy]

For the newbies...the 1500' rule is the measurement from the starting line to the entrance pin of the first turn at the Nationals.

Secondly, the Yamato gearcases do have several measurements on them...there are specs to prevent all out shaving/shaping. Radious at the nose, thickness, skeg, etc... But there was no rule on height of the case...from the bottom of skeg to the top of the case where it bolts onto the towerhousing. Shave the top of case...now your prop shaft is higher.

Once you get contours done right...isn't much play room to tinker. You'll get busted. I can't recall the last time a Yamato got tossed for a gearcase at the Nationals.

Ed's opinion is proven by fact. No 302 has won the CSH Nationals...where the fastest 102's come out to play.

Pretty discouraging to watch guys with 302's beating their brains out fighting that battle. I empathize with them. Of course, I'd have bought a 102 instead.

Dana, 302's have won the OSY400 Pro Nat's before though right? And Pro does not have a height restriction......

[dholt]

Darren,

I don't know if a 302 has won the OSY 400 Nats. before. Never been to those events.



Someone fill me in on this question. Would a 302 on CSH pump OK higher than 1/2"...or can the 302's even come close to running at 1/2" and still pump well enough?

[22W]

Dana, that is what this discussion is about. Most guys can't even get as high as 1/2 without smoking a 302.

[mercguy]

Darren,

I don't know if a 302 has won the OSY 400 Nats. before. Never been to those events.



Someone fill me in on this question. Would a 302 on CSH pump OK higher than 1/2"...or can the 302's even come close to running at 1/2" and still pump well enough?

let me try this again, as somehow I delted my last response...

yes, a 302 has won the OSY Nat's ( I do not attend either) and also set the record I do believe.

I have ran my 302 on my previous Darneille hydro at 1/2" and above and never smoked the motor. I believe boat design and bottom design are more critical with a 302. I do not believe it is the lower units, as there are identical (except for the rear bearing carrier). Water outlet hoses.......... allow the outlet size to be increased......

[drbyrne55]

smoking 302's

Dana, that is what this discussion is about. Most guys can't even get as high as 1/2 without smoking a 302.

Ryan,

Our 302 set up runs great at 1/2 so far (355 temp) .... prop selection does seem to matter....

I'm just newbie learning from the experienced....

[Cameraboy]

Ryan,

Our 302 set up runs great at 1/2 so far (355 temp) .... prop selection does seem to matter....

I'm just newbie learning from the experienced....

There's a thread on here from a few weeks ago about Yamatos and pumping water. Props, height and angle, driver position in the boat, were all among factors listed. Another factor is that these stock racing motors were not designed to run as high as we seem to want to run them. Dan, at the rate you and Sean are learning, most of us will be coming to you guys for advice.

I'm a bit of a newbie too, and would like to hear more about this 1,500' or 1,000' buoy at Nationals. Why is it different from what is required of a regional or divisional course? If there is a safety need to stretch the field out before the first turn, then why do we allow 12 boats in a heat? Wouldn't the same thing be accomplished by a wider radius turn?

I have both a 102 and a 302, each on their own boat. The 102 rig is pretty fast, but we have a 102 specific prop on it most of the time. We need to trade off a little top end for corner speed (of course, using a long run to the start, maybe I'd feel different). The 302 rig still needs some work, but it isn't a top end problem, and we are still playing with the 302 props.

We had a race this year that really showed the difference between the two motors. The 102 rig had top end on a .80 mile course with very narrow turns. The 302 rigs were able to keep speed up on a tighter line through the turn and accelerate off the turn better (that torque). That said, the 3 boats were about even - it was all start and lane choice. The 302 is the dominant motor out here, but you can still mix it up with a 102.

But I also bought Montoya's last set of 102 coils last season, and I'm an electrical problem away from having a very strong doorstop. We'll run it until it poops out, and then it's another 302 and sell the 102 for parts. Hopefully it lasts until I'm not buying the motors

[NUT2F]

a 302 has won the osy nat'l, Pro has the same height as CSH

[42R Dad]

J Michael won the Pro National in 2002 and has run out front in 03 but had a plug wire fall off. He did win the final heat. He also broke a 102 OSY record in 2005. He can run 1/2 inch and still pumps water. This is with our 302.
He would suggest no changes.
J Michael won Nationals OSY with a 102 and a 302. I am talking with him on the phone as I post this. He has run on the OSY records and CSH with the 302.