New 321 motor?

[daveracerdsh]

One thing is very clear from this informative thread......people are very excited about the 302 SSH class....which I sure do appreciate.And trust me, Jeff, myself, Elec and the rest of the 302 Commitee are very well aware of the issues involved with bringing in the new 321 engine into the class.....we have little choice but to do so, which is obvious. Thank you so much for your support .

[Lee Sutter]

Hello Racers,
I like this post as 6,000 people are following this topic. And, many are trying to resolve a very critical situation that will pave the direction of making a the 302ssh "Sealed" class a way of life in stock outboard racing. So, I have a few questions:
1) Is there a "Mission Statement" for the 302ssh class? If so, where is it? If not, why not?
2) What is the quantity of 321's currently on hold in United States port/s?
3) Is there an ETA date from the U.S. Importer/distributor? What are the obstacles?
4) What is the turn around time from the time the engines arrive at the U.S. distributor to get them delivered to the user?
5) Are there enough 321 engines availble to support a 100% switch to running just the 321?
Without answers to the above questions, I think it will handicap making a informed decision.
Thank you,
Lee Sutter

[Ram4x4]

Well, the APBA site says this on the 302SSH class:

"The intent of the 302 Super Stock Hydro (302SSH) is to have what could be our first ever “stock” outboard class in APBA racing. This class shall lower barriers to entry, have very low start up costs and provide a place for new members to hone their racing skills before making a transition into the faster classes. It will also offer a class to current drivers that no longer wish to race at higher speeds"

[GrandpaRacer]

There is nothing in this mission statement that says this is to be a single engine class. It is a class designed to be a controlled (sealed) slower class. So the commission can easily slow down faster motors with weight and height rules. Adding the 321 is the only choice to keep the class active and open to new racers. Controlling the top speed is the job of the commission. Seems simple to me.

[Ram4x4]

I don't know if that is considered to be the "official" mission statement for the class, but I think everyone in and around it pretty much understands the point of a "sealed" class.

As pointed out, if we allow a different engine in and then start trying to make parity by adding weight, etc then it is no longer any different than other classes in SO with their restrictor plates, etc and pretty much defeats the entire purpose.

I know switching over to 321 is not going to be easy for some and it's not going to be free. If the intent is to keep a single engine, sealed class though it has to be done.

I support the single engine only idea, even though I myself might not be able to get into the class for another year.

I think the issue is very simple, we need to move to the 321 only. The hard part is how do we get there without killing the class, keeping participation up and without forcing current class drivers to just fork out the money for a new motor right off the bat.

[Lee Sutter]

Hi Grandpa Racer,
I want to think it's simple too. And, I think there are lots of logical options to transition to running the 321 on an exclusive basis. Why not the 302? Because we need to run one engine after we get enough 321's. And, why try to parity an old engine when we have a new engine. Oh, 302's are still worth $2k to $3k. I have a 321 that you can use if you want to get some numbers.
Lee

[flatsmoke]

One more question? Is the SORC keeping a log of all the engines that are officially "Sealed"? And, when the seals are broken? I would suggest this too. I think every 302ssh sealed motor should have documentation that is recorded and kept by the SORC.

[daveracerdsh]

Flatsmoke: A racer that buys a sealed 302 motor can do whatever they want with it in regards to racing.....if they want to run it in 302 SSH the seals must remain in place....of course motor can be run in CSH, 20SSH, CMH, etc.....just change the gear foot, However...there are no rules at this time stating that you must keep the seals on. We do have documentation that of the number of motors out there (serial numbers) . However, there is of course nothing to stop a racer that owns one to break the seals and do whatever to the motor. Of course, that motor is no longer eligible for 302SSH. We are also looking at exchanging 302 parts with 321 parts to keep the motors all the same.....I do feel that this needs to be a "one motor class" However, as Yamato continues to upgrade motors, this is going to be somewhat of a chore. If anybody has specific ideas, thoughts, you name it....please call me at 425 246 4710, or email me at Daveracerdsh@aol.com.

[Harold8]

Flatsmoke: A racer that buys a sealed 302 motor can do whatever they want with it in regards to racing.....if they want to run it in 302 SSH the seals must remain in place....of course motor can be run in CSH, 20SSH, CMH, etc.....just change the gear foot, However...there are no rules at this time stating that you must keep the seals on. We do have documentation that of the number of motors out there (serial numbers) . However, there is of course nothing to stop a racer that owns one to break the seals and do whatever to the motor. Of course, that motor is no longer eligible for 302SSH. We are also looking at exchanging 302 parts with 321 parts to keep the motors all the same.....I do feel that this needs to be a "one motor class" However, as Yamato continues to upgrade motors, this is going to be somewhat of a chore. If anybody has specific ideas, thoughts, you name it....please call me at 425 246 4710, or email me at Daveracerdsh@aol.com.

That sounds interesting. Are you saying that a sealed 302 might be able to be upgraded to a 321 ?

[Ram4x4]

Yamato UK has this comparison chart on their site:

http://www.yamatoracing.co.uk/model-321/4587843953

It shows some of the differences in the parts (but not all).

Would also like to see internal component differences, but those aren't shown.

[gabengail]

Do unload the 321 manual also. Specifications are in the manual. I see no difference when comparing at first glance.

[Ram4x4]

Ugh, tried using the "add a table" option to post the specs of each side by side, but it keeps erroring when I try to post it...sigh.

Anyway, the the 321 makes max torque at 6,000 RPM where the 302 does at 5,500 RPM.

321 max HP is at 6,800 RPM and 302 is 6,600 RPM.

Theoretically, the 302 should have more low end grunt since it's torque curve is fatter and lower in the RPM range according to the published torque curves.

The 321 should be a faster top speed engine due to higher RPM power figures. The 321 makes max power just 800 RPM above max torque. The 302 has to stretch its torque curve 1100 RPM to max power. That tells me that above max HP RPM's the 302 is losing torque at a quicker rate.

The 321 could probably stretch it's RPM's a little more and turn the prop faster, translating into higher top end, all else being equal.

I'm guessing the props that come with each are different. It'd be interesting to see performance numbers with the each engine running the same prop.

[Ram4x4]

The motors are almost identical in specs in most of the measurements. The differences are in RPM for max HP or max torque with the 302 generating them at lower RPM by 200RPM and 500RPM respectively.

The second difference is transom height.

Theoretically, the 321 has the potential to spin a prop a few hundred RPM faster if all else is equal which may indicate a higher top speed on straights. The 302 should have a little more acceleration punch due to torque rise being fatter across RPM band (looking at the torque curves for both).

I'd be interested to see what the differences are, if any, in the stock props that come with the engines. I suspect the two are different.

Yamato 321 Yamato 302 Horse power 33h.p. @ 6,800 rpm 33h.p. @ 6,600 rpm Maximum Torque 26.8 ft lbs at 6,000 rpm 26.8 ft lbs @ 5,500 rpm Bore X Stroke 66 mm×58 mm 66 mm×58 mm Piston Displacement 396. 9cc / 24.2 cubic inch 396. 9cc / 24.2 cubic inch Piston Clearance 0.004 " ~ 0.005" 0.003" Port Timing Intake 55 degree B.D.C Intake 55 degree B.D.C Port Timing Exhaust 85 degree Exhaust 85 degree Piston Clearance Volume 26 cc 26 cc Induction System Reed Valve 1 set Port size 29×13 mm 1 set Port size 29×13 mm Carburetor One Ventury 28mm 28mm Flywheel weight 2.86 lbs.(Min) 2.86 lbs. Gear ratio 14:15 14:15 Fuel Regular petrol Min. 86 Octane Regular petrol Min. 86 Octane Fuel tank capacity 2.3 Liter / 0.6 Gallon 2.3 Liter / 0.6 Gallon Fuel mixing ratio 30:1 30:1 Weight 92 lbs 92 lbs Transom height 11.2 inches 13.5 inches Ignition timing 0.200" to 0.250" B.T.D.C. 0.200" to 0.250" B.T.D.C. Compression Ratio 8.6 8.6

[Ram4x4]

oh, it did post the table...hmm..gave me an error when I hit the post button...odd.

[Graham 18ce]

I believe most agree that the 302 sealed class is worth keeping and has consistant growth from both new name and household names.
I believe most understand that in order to keep that momentum, the 321 has to be the motor, the only motor.
The biggest problem is how to get there without upsetting everyone, or costing a large sum of money to some teams that are more paycheck to paycheck then the other.
The big problem we always have is setting and sticking to an end date of a motor.
New motor is here. Deal with it in this class. It is here for 2016, nothing else. The 302 end date is the question.
To help the lower budget teams, or the new guys that just bought a motor this season or last, why not have both for one year maybe two, then the 302 is out. And stick to it.
Class growth on the 321 will continue, old names and new names have a place to learn for a
Season or two and can decide that they like the format and then move to CSH or other classEs or by a 321.
Obviously a certain amount of testing prior as a box stock motor to compare to a 302 would be needed, but I can't see a
World of difference anyway.
Popcorn time!

[Ram4x4]

	Yamato 321	Yamato 302
Horse Power	33 HP @ 6,800 RPM	33 HP @ 6,600 RPM
Maximum Torque	26.8 lb-ft @ 6,000 RPM	26.8 lb-ft @ 5,500 RPM
Bore X Stroke	66mm X 58mm	66mm X 58mm
Piston Displacement	396.9cc	396.9cc
Piston Clearance	0.004" ~ 0.005"	0.003"
Port Timing - Intake	55 degrees BDC	55 degrees BDC
Port Timing - Exhaust	85 degrees	85 degrees
Piston Clearance Volume	26cc	26cc
Induction System Reed Valve	1 set, port size 29x13mm	1 set, port size 29x13mm
Carburetor (One Ventury)	28mm	28mm
Flywheel Weight	2.86 lbs (min.)	2.86 lbs
Gear Ratio	14:15	14:15
Fuel	Regular gas, 86 octane min.	Regular gas, 86 octane min.
Fuel Tank Capacity	0.6 gal.	0.6 gal
Fuel Mixing Ratio	30:1	30:1
Weight	92 lbs.	92 lbs.
Transom Height	11.2 inches	13.5 inches
Ignition Timing	0.200 to 0.250 BTDC	0.200 to 0.250 BTDC
Compression Ratio	8.6	8.6

The 302 makes more torque in the lower RPM range looking at the published torque curves (meaning RPM for RPM it makes more power in those ranges). The 321 doesn't make max torque until 500 RPM over where the 302 does and does it within 800RPM of its max HP. The 302 makes max torque sooner, but has to stretch it out for 1100 more RPM to max HP. This indicates that by the time the 302 reaches its max HP the torque is dropping off pretty good.

The 321 could probably go a few hundred RPM more before it starts to drop torque significantly. To me that indicates the 321 is a "top speed" engine vs an acceleration engine as compared to the 302.

I'm guessing the "stock" props that come with each engine are probably different. I wonder how running a 302 prop on the 321 affects speed and acceleration, and vice versa.

[Ram4x4]

sorry for the multiple table posts...I kept getting an error and didn't see the post until a few minutes later.

[daveracerdsh]

The 302 ssh committee is on top of all of this...trust me folks. Trust me. That LAST thing we want to do is mess up the best thing going in stock racing....again....if you want to chat about this, e mail me at Daveracerdsh@aol.com or call me at 425 246 4710. We want to have as much info as possible from people. Dave

[Ram4x4]

I got it!

Here's how we do this....at the driver meeting, we don't just trade props, we trade the 321's and 302's too!

sorry.....couldn't resist...

[65R]

4 stroke Yamato, new motor for 2017..... Just kidding

Found Photo on euro website, Crap! We'll all be running 4 strokes eventually.

[PRO-MOTIONRACING]

Transom Height

11.2 inches

13.5 inches Is the 321 actually shorter?

[GrandpaRacer]

This is wrong, they are both the same. Another error is the weight, the air box is bigger and heavier, the tower is bigger and much heavier on the 321.

[Howie Nichols]

Out of curiosity would the membership be interested in a phase out of the 302? In other words, for 2016 and 2017 say both the 302 & the 321 are legal then in 2018 just the 321 is the legal motor?

[Ram4x4]

Short of some sort of subsidization, I don't see how we can go straight from 302 to 321 without making unfair financial demands on some racers. The class is unfortunately a victim of timing. Not sure anyone could foresee the 321 coming out 2 years after 302SSH was created.

Although I believe in a "one-motor sealed class" if a slow phase out with both motors in the class provides the means to do it with the least amount of financial burden, then it certainly won't keep me from running in the class.

[Hutch06]

I would support a phase-out process due to ability to not complete all conversions of motors to make a complete swap... however, I think anything more than a year is a stretch.