Yamato Cooling Test; Phase 2 Summary

[GrandpaRacer]

As most of you know the Cooling Team has continued the evaluation of an external water pick up for Yamato engines. A report has been sent to the SORC. This work has been performed by Matt and Val Dagostino, Lee Sutter, Ken McMurphy, Adams Racing, and Tim Weber. Lee Tietze has manufactured several test devices that allowed the Team to do all the testing. Testing was performed on both East and West coast in cool water at or near sea level. Many test runs were made with 20ss hydros, C stock hydros and a C Stock runabout. The motors tested were 2ea 321s, a 302/321 hybrid (302 powerhead on a 321 tower) and 2 ea 302s. Pick up tubes were attached behind the cavitation plate, above and below it, with a ½ inch tube, a 3/8 inch tube and a 3/8 inch tube crimped (like the old Keller Speedo). The best and final design is shown in the attached photo and is the crimped 3/8 tube design mounted above the cavitation plate. This design cooled all motors in all tests and if approved will be made available in a kit from Lee Tietze for about $50.

In CSH configuration typically the Cool Tool (as it will be called in Lee Tietze catalog) lowered the CHTs of 302s about 45 degrees and 321s about 100 degrees to around 300 degrees CHT. The tube slowed top speed about 0.8 mph and did not affect handling.

In 20ss configuration at ¾ inch prop height the Cool tube was equally effective but slowed only a few tenths mph. When the prop height was raised to ½ inch, the CHT went up to around 315 degrees (321) and the speed went up about 1½ mph.

In Summary the Cool Tool:

• Cools all 300 series engines at legal heights
• Maintains a steady water flow
• Does not affect handling
• Is easy to install

[Andrew 4CE]

I commend everyone who has put all this effort in and made it public... I don't have a solution, but I believe any change remotely like this is the wrong solution. This lets someone with the proper tools ($$$) easily dial in the ideal motor temp and the people that have the money to monitor temps like that and the time to test for hours on end to figure out the most ideal situation of an attachment that is adjustable will find more speed than anyone else. Not that they shouldn't be rewarded for that effort... but it's not something everyone can do. Also the water temp is different at different race sites and times of the year, so someone could create a spreadsheet on water temp and how that effects the engine temp... every race day could be adjusted to ideal motor temp for further advantage. I believe doing something like this will further divide last to first place. If the attachment is made un-adjustable, it creates another critical inspection area. I don't envy anyone on the SORC to try and figure this out...

[stockc]

Realize that I have been busy lately... but when will NASCAR teams be entering Ma and Pa Stock Outboard Racing(-:

I support the attachment having ample adjustability to completely meet what could be a wide range of individual cooling requirements. IF passed, installing one is completely voluntary, what sense does it make to create a bunch of rules, further complicate inspection for an optional, non performance part. No inspection warranted. I've not witnessed the hang a tube off your motor speed secret being used at the races I attend. Those who already cool at APBA stock heights will continue having the optimal configuration, which also has the greatest potential for speed.

[guedo499]

Andrew - I'll help you out: Yamatos create the most HP when the top cylinder, measured with a spark-plug adapter, is at 330 degrees.

[Andrew 4CE]

That's one piece of the puzzle... now to buy a temp gauge for engine, temp gauge for lake water and find out where the best adjustment is for any given situation and with which prop I have on. Then adjust every race day to hit 330. I can do it... should be easy for the newbie to figure out too.

[Harold8]

I think most people will be happy that they don't burn up their motor at each race!!

[61-W]

All brand engines cool differently at each race location due to actual water temperature of the day. It doesn't matter if it has a water pump or force feed cooling. Everyone is racing on the same water each day.

Jeff Scheffler

[Big Don]

At the end of the day, the same fast guys will continue to win. Why? Because they work at it.

[Racerkyle20]

Bingo......!

[Matt Dagostino]

WOW............perhaps Big Don is warming to the COOL TOOL...........Merry Christmas!

[adamallen]

If that's the case why not just lower the max height to something manageable?

Some would say that prop boxes' would be destroyed. That may be, but I see it like this:

- If the ;Cool Tool; is approved, everyone will be testing props to find an additional MPH
- If the height is lowered, everyone will be testing props to find an addtional MPH
- If nothing is done, everyone will be testing props to find an additional MPH

In all of these scenarios BigDons point rings true. That's why if I were voting I would vote to lower the height to something that pumps water and is manageable.


If you lower the 20ssh height to say 1 inch for yamatos dropping it down from 1/2 inch, then drop the SW 20 the same. No perceived advantage by anyone.

[Hydro doc]

If we allow the head to be cut, allow fuel pumps, and to grind on lower unit($$$), why not allow a hole in housing that is very simple(no $). We check the height, so it is not a speed advantage. We are making this too complicated.

[Hydro doc]

If you allow two ways to cool, a hole or pickup, most would select a simple hole.

[JBM]

I love the idea of simply enlarging the existing water pickup hole, but all the tests I've seen on here show it doesn't work. Have you actually had success with this?

[deeougee]

Why would we lower the height for 20ssh again? First time was for the 302. I don't have a desire to go any slower. How about we raise the height instead back to the original height? The Y80 guys have had this figured out a long time ago. So the 20ci guys are going to be penalized to accommodate those with 302's and 321's that don't want to put the work in to run at 1/2" if they so desire? Every 1/2" raise and lower in engine height equals about 2 mph. If we are going to allow external water pickups why wouldn't we leave it open to do what anyone desires? As an 80 owner I would want to mount the pickup on the boat. Why? To take advantage of the extra speed available. There are some of us that have tried this stuff a long time ago. This is just opening pandora's box again. How about this? Guys with 302's and 321's run lower but we play with the restrictor opening for the sake of parity.

[Steve Dunn Racing]

Thank God for the mod catagory

[Tom Cronk]

And the PRO category,USTS.

[GrandpaRacer]

Our goal was to find a way to cool the 321 (and the 302 to a lesser extent). The external pick up does that. Parity is for some one else to deal with. The Cool Tool is not the only option, there is at least one other being considered. We took this task upon ourselves and any other racers can do the same. Go test your ideas and write it up in a report to the Stock commission. That way they will have several good ideas to choose from, what could be better?
John Adams

[daveracerdsh]

I do not have a dog in the fight, other then wanting to see stock racing grow. I want to thank John and crew for all the hard work they put in....this is a no-brainer......

[HydroKyle93R]

What is the cylinder head temperature of a 300ssH running at 1 3/8" below the bottom of the boat?

[GrandpaRacer]

Good question, also what is the CHT for a 302 at 1 3/8? In the races in Japan they told us they hit 370CHT at the end of the shoot with the 321.

[Joe J]

Kyle: My 321 runs at about 320 degrees in the 300ssh configuration

Joe

[daveracerdsh]

Kyle: I assume you are asking about 300ssh class....I have not heard of anybody cooking a sealed motor yet due to lack of water....maybe somebody out there can provide info on this? Dave

[Harold8]

Which gets back to lowering the height numbers instead of changing the motor. People are probably going to have to test props no matter what is done anyway, so do the easiest thing and drop the motors down a bit.

[deeougee]

Drop them to what? To run ASH speeds? Lets clarify something engines running 300ssh are not having issues. SOME PEOPLE running 20ssh and CSH are. Especially people with blueprinted engines. Here's another thing, people running a stock 321 in 20ssh and CSH are not going to beat blueprinted engines so get that out of your head! You will need a separate non sealed 321 if you want to compete for the win! At this point I would suggest Y80 owners seriously contemplate running BMH, because that's where we are headed. Would really like to know what the proposal to get rid of 20ssh was. That way with no 20ci engines to speak of there is no reason to continue the class! There are not enough SW20's running to support the class with that engine alone. Remember the basis of 20ssh is the 20ci engine or did we all forget that?

[csh-2z]

Maybe we should put the Yamato 80 into BSH so they can support the future of the Sidewinder by growing the class AND give these older motor owners a place where they can be competitive. It might put BSH on schedules where they currently are not. Still allow both in 20SSH