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NOT HAVING A NATIONAL LEVEL HURTS RACE CLASSES LIKE T CLASS

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 PostPosted: February 7th, 2019, 4:23 pm   
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Grass roots racing is a good feeder to get racers to compete at a higher level. There is a BIG difference in rule enforcement and tech inspections at the higher levels and especially at APBA National Championships and UIM World Championships. We have been very successful in developing World Class racers in many different classes thru CBF. These racers not only run in the National events, but are racing in our local events.
THEY ARE THE YARDSTICK FOR LOCAL RACERS WHO RACE AGAINST THEM IN THE LOCAL RACES! Other racers know they are legal and lean on them for information. Its the National racers that help keep other racers legal.

RACERS WOULD LIKE TO WIN AND BE COMPETITIVE!

MOST new racers are VERY disappointed when they first start racing.....they are not competitive. They don't realize that it is the small things and driving experience that makes the top boats better. They assume the top runners are CHEATERS and he or she that cheats best wins. THAT IS WHERE HAVING THE NATIONAL RACERS IN A CLASS MAKE THE DIFFERENCE.

Soon as you have the word "MODIFY" in your rules you open the door. IN OPC RACING NO MOD CLASS HAS LASTED MORE THAN A FEW YEARS other than F1. You have to be very clear and exact as to the extent you can modify.

When T850 voted in the modify rule for the OMC 56......the playing field changed.
The lower compression [from 180 to 160] SST60 was the bench mark motor for the 56 OMC.
We had the APBA spec sheet and the parts book.
I thought was.....most 56 racers ran the fishing motor......they should be allowed to spec their motor up to the SST60 motor and not have to buy an expensive SST60 long block.

It did not take long for the 56 fishing motor performance to jump and soon eliminate all the 49 OMC, 60 Mercury and yamaha 70CES from being competitive. That left only the SST60 as competition.
As soon as these mod fishing motors got successful.......racers with funds went to their engine builder for a better motor......a competition as to who could build the strongest 56 started.......The original rules had boats running 64 to 70 mph.....within a few seasons the top boats ran over 75 mph......now the pure SST60 at 180 compression was not competitive.

The 160 compression SST60 HAS TO BE THE YARDSTICK FOR THE 56 MOTOR
The racers themselves can make the T850 class successful again.
T Class history and common sense is all that is needed.
Without boats in the race.....there is no race.
We had 23 boats in T750 and T850 before the change......we had 0 accidents before the change......we had different winners before the change
We had many years racing the 56 motors and lots of knowledge about the 56 motor.
- NO 56 should have a jet size larger than the 73D...in fact ALL SST60 tunnel racers run 72D....most 160 SST60 T850 guys ran 72D as well. If your 56 needs a larger size than a 73D.....common sense tells you are making more power than the yardstick motor....we had motors running 76 to 80 jets
- same goes for the cylinder head.....no motor should have a head smaller that the 160 SST60.....that's 30 to 31 cc

SIMPLE TECH INSPECTION FOR THE T850 OMC....
- Make a go-no go gauge that measures thru the spark plug the space from the top of the piston to the top of the cylinder dome.
This metal spacer block is the measurement off an SST60 160 compression legal motor. If the motor rotates with the block in place and not lock up...the motor passes that test......remember history showed us that a 147 to 155 compression is best so your head can be a larger volume.
- Pull a carb jet.......use a 74 jet drill bit as the measuring tool....if it DOESN'T go thru the hole...the motor passed


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 PostPosted: February 7th, 2019, 5:26 pm   
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Hounddog wrote:
SIMPLE TECH INSPECTION FOR THE T850 OMC....
- Make a go-no go gauge that measures thru the spark plug the space from the top of the piston to the top of the cylinder dome.


Kinda just playing devil's advocate here, mostly so people can maybe educate me...
I'm not seeing how this measures the chamber volume. Chamber height is not the only variable in the volume of the chamber. Shape and diameter also are part of it.
Am I missing something in envisioning how this could work?

Also, for go/no go for jets, what happens if the jet's orifice is out of round: for example the max diam round gauge that goes through is 72 but it flows like a 76 because the jet orifice is oval (modded by a cheater!)

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1989 Voodoo Yamaha 70
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 PostPosted: February 7th, 2019, 7:23 pm   
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mattmak wrote:
I'm not seeing how this measures the chamber volume. Chamber height is not the only variable in the volume of the chamber. Shape and diameter also are part of it. Am I missing something in envisioning how this could work?
Matt, go and look at the SST60 spec sheet posted on another thread....look at the cylinder head diagram...it shows the pocket depth of the head that produces the 28.5 cc volume. In coming up with the 160 lb compression rule MANY heads were cut different amounts and race tested to find one that would make the SST60 less performance equal to the other motors in the class. The actual tests showed there was little difference on the race course between an SST60 with 150 compression to one with 160 compression. The T group decided on 160. So for the SST60 head 30 to 30.5 cc will produce 160 compression on a spec SST60.

Also, for go/no go for jets, what happens if the jet's orifice is out of round: for example the max diam round gauge that goes through is 72 but it flows like a 76 because the jet orifice is oval (modded by a cheater!)
We know that the orifice in the jet should be round......if it is oval it is not legal regardless of its size.

Matt as a point of interest here is some more history on the 56 compression testing.
The boat we used for race testing was Dave's 411 Critchfield...with the pure SST60 motor it ran 73.7 mph on GPS.
Dave ran a different cylinder head every race day.
I had done some GPS readings at Waterford on a number of boats running the fishing motor. Riley's boat running a bone stock non rebuilt 56 with a 160 compression head ran 70.5 mph........other boats ran 64 to 68 mph.
My goal was to get Dave's boat to run 67 to 69 mph. Jimmy Allen needed a boat to race at Waterford.....i assembled a blue printed pure stock fishing motor with a 155 lb compression head. Jimmy ran it and said it was the best boat he had ever raced...he won every heat that weekend....I got the boat back and GPS tested it at the cottage the following weekend. It ran 68.2 mph, but the acceleration to top end was super compared to the SST60 power heads we were testing. Finally I got the SST60 to perform at Dunnville. Dave won one day of racing and finished top 3 the other. The motor made for great racing. It lost 2 boat lengths out of every turn due to the acceleration compare to the fishing motor and made up the 2 lengths in the last 1/4 of each straight.


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 PostPosted: February 7th, 2019, 9:15 pm   
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Many times in racing you find sandbaggers running in your class. These are the racers that race non legal equipment and avoid being inspected by not finishing top three. It is obvious to the experienced racer watching the races that boat is illegal and it hurts the class. When we started racing in APR Superleague Jeff Titus told us at our first race that every SST60 boat that came from Ontario Canada to run APR ran illegal equipment. We ran 9th the first race.....not too bad when there were 19 boats racing. Our second race were finished 5th out of 20 boats. That's when Jeff informed me we had won the "LUCKY DOG" draw. A draw out of a hat containing all boats other than top 3 and that boat would be inspected along with the top 3. Inspection is first fault and your DQ'd. Well be passed inspection, we were legal and it was interesting how fast that news got thru the pits and how many racers stopped by to talk to us afterwards. I think if we had the lucky dog draw at our races many current racers would stop racing.


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 PostPosted: February 7th, 2019, 9:21 pm   
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Hounddog wrote:
I think if we had the lucky dog draw at our races many current racers would stop racing.


We already don't have "many" racers currently racing!

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Critchfield T850 OMC 75 49ci
Delta T750 Yamaha 55
1989 Voodoo Yamaha 70
1980 Thundercraft v142 Restored


Last edited by mattmak on February 7th, 2019, 9:58 pm, edited 1 time in total.

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 PostPosted: February 7th, 2019, 9:22 pm   
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Hounddog wrote:
Riley's boat running a bone stock non rebuilt 56 with a 160 compression head ran 70.5 mph........


Oval Port or Bridged Port?

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Critchfield T850 OMC 75 49ci
Delta T750 Yamaha 55
1989 Voodoo Yamaha 70
1980 Thundercraft v142 Restored


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 PostPosted: February 7th, 2019, 9:25 pm   
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Hounddog wrote:
We know that the orifice in the jet should be round......if it is oval it is not legal regardless of its size.


A regular human being would be able to see with their eyeballs that it is not perfectly round?
I'm thinking these differences would be subtle.
I guess you could use a light source to look for out-of-roundness..

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1989 Voodoo Yamaha 70
1980 Thundercraft v142 Restored


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 PostPosted: February 8th, 2019, 1:07 am   
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mattmak wrote:
Hounddog wrote:
I think if we had the lucky dog draw at our races many current racers would stop racing.


We already don't have "many" racers currently racing!


I was referring to all classes including stock outboard.


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 PostPosted: February 8th, 2019, 1:08 am   
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mattmak wrote:
Hounddog wrote:
Riley's boat running a bone stock non rebuilt 56 with a 160 compression head ran 70.5 mph........


Oval Port or Bridged Port?


1986 bridge port


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 PostPosted: February 8th, 2019, 1:11 am   
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mattmak wrote:
Hounddog wrote:
We know that the orifice in the jet should be round......if it is oval it is not legal regardless of its size.


A regular human being would be able to see with their eyeballs that it is not perfectly round?
I'm thinking these differences would be subtle.
I guess you could use a light source to look for out-of-roundness..


If it was so subtle, not noticeable and the 74 bit would not go thru.....it would pass


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