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Question and Answer
I have a Critchfield SST 60 outfit. I am trying to decide if I should change the motor and run VP75 or cross the border and race in T. I get the 160 lb. compression rule. When my motor needed rebuilding after 10 hours of running, the compression had dropped from 180 to less and 165 and the boat ran like a slug. I lost over 10 mph and ran low 60’s.
Any advice?

We would welcome you to the T group. The dollar is close to par. Our beer is stronger. You will have lots of boats to race against. If you think low 60’s is slow, you will be even more disappointed in VP75 where the speeds are low 50’s. What happened to your SST 60 motor is normal. T is NOT a super stock class. Running an SST 60 with our rules requires spending more money and a much better set up to be competitive compared to the other T motors. With the SST 60 motor you need to run smaller diameter props to get it to work. Set up correctly you can get a mile or 2 more top end. But that is your only advantage. You’re going to rev the motor close to 8000 to get it. The guy your racing may only have a $700.00 motor. Just a fishing motor with a head. He will tough to beat. So my advice is. Unless you want to spend the money, don’t . The other motors last years not hours.

Question and answer
I just noticed the Tuff critchfield thread. Those boats are going to be very light. Will they be allowed to race in the T classes? What about the aluminium boats?

Yes, but they will still have to meet the legal T class weights of 550 lbs. for GT30 , 625 lbs. for T750 and 725 lbs. for T850. They will just add weight if? they need too. When their not racing they take the weight out. Adding weight is very common in SO classes. If successful Mark will sell these to non racers as well. The fact that they race them can only help his promotion. If? these do come out light then they will be perfect for GT30 and we can add a number of new young racers to the sport. Its a win-win!
An aluminium boat CANNOT RACE IN T. The hulls must be composite. Top Gun and I have always wondered what a aluminium Critchfield would look like and run like. I have an aluminium Mini Most Sea Flea. It is at least 30 years old now and it will last forever.

Cutting a 49 OMC head.
I got this info off Ron's site

Milled Stinger head
1975 Stinger with .065" milled head pulls 165-175 psi.

I would be cautious doing this. We took .060 off a head and got exactly 160. The legal limit. I am not 100% sure if it was just the head or maybe lack of cooling, but the powerhead got ring damage in short order. Was there any gain in performance???

T BOAT COLOURS
If your painting or buying a new T Boat this winter, please think of the people scoring the heats. We have a lot of red and a lot of white on our current boats. Try and use some other colours. Two colours works well. Maybe we should have a thread with pictures of the current T boats.

Question and Answer
I have seen at least 1 used ETEC and several used 4 strokes in the 25 to 60 hp range at good prices. Which one do you suggest?

I did mention on another thread that I don't have enough knowledge about these motors to offer an opinion. I have actually made offers on several of these motors and if I get one I will certainly put it on a raceboat. On hear say I have been told that the ETEC is better especially in GT30 and in T750. None of the 70 hp models in their stock form are competitive with our T850 motors. T class wants to promote the new motors. With people now building new lighter and stronger Critchfields I am sure we will be able to test some of these newer motors and if necessary revise the T rules to make them competitive. The goal of T is to have 3 class speed levels ...a 50 mph class [GT30]...a 60 mph class [T750] ...a 70 mph class [T850]. It would be ideal if a racer can start at 14 years old in the 50 mph class. Then at 16 move to the 60 mph class and later advance to the 70 mph class. Better still if they can do it without buying a new boat every time. A suggestion made by TOHATSU was to allow their new 50 hp motor in GT30 but at the 625 lb. T750 weight. That way the racer can keep the same boat. We need to get a few combinations tested and go from there. My focus this year is to get a good T750 field and have them race in their own group separate from T850.

Question and answer
I have just started to rebuild my 1986 56 cubic inch OMC and I have a few questions.
[1] the sleeves are not all in the same positions and there is aluminium showing in some of the ports. Is this normal? What can I do about it?
[2] the crank has a few marks where the rod mounts on number 2 cylinder. They will not polish out. Is the crank OK?
[3] the bearings look good. Can I reuse them?
[4] I want this motor to turn 8000 rpm what fuel mixture should I run?

First off you have some issues with that motor. You didn't mention how it ran before you disassembled it. So my first suggestion is to take it to a dealer and have them look at it. You maybe better off with another powerhead. Your questions are all good ones, so I will answer those.
[1] You have a first year sand or production block 56r. They had problems with the sleeves shifting in the blocks. That is what is happening here. I bet number two cylinder is the worst and that may explain the crank problem. You can have the sleeves repositioned back to their correct positions or if it is only minor just grind out the aluminium in the port.
[2] It is now possible to rebuild these cranks. The cost and the result is not what I would use for a race motor. Find a good crank.
[3] The motor is a USED 1986. I would use all new bearings.
[4] With stock porting [legal in T] Your not going to see 8000 rpm. That is where the SST60 motors run. Chances are you will see between 6400 and 7000 rpm. It can be that big a difference. It doesn't mean your motor is a dog because it turns only 6400, it is because these are stock motors and they can really vary. Your prop selection has to suit the motor you have. You can't assume that what works on another boat will be the best for your boat. With 150 to 160 compression I like premium Shell 32 to 1 mix.

Question and Answer
I have been looking for a while trying to find a 1986 to 1988 56 powerhead. How come you guys find them and in some cases they still are in good condition?

I see you live in Florida. There is a big difference in your boating season compared to ours in Canada. You use your motors 12 months a year. Up here many motors are only used 2 months of the year. So a motor up here that is 6 years old is equal in wear to a 1 year old motor down there. We only run in fresh water up here in Ontario, so everthing lasts longer. Your northern states have similar seasons to us. I suggest you watch ebay and look for a powerhead from there. You don't want to have one shipped from Canada. The cost increases once the item has to cross the border.

First bit of information comparing the oval port to the bridgeport 56 blocks from a person who was run both blocks.
QUOTE:
-Oval port has a wider power band overall
-Bridge port has a more peaky power band
-You can do just fine with oval
He mentioned about sealing the relief holes. You CANNOT do that under our T rules. The wider power band may? benefit a T boat by improving the handling and the acceleration..
There will be 1 or 2 oval blocks in T850 next year. Ted at Speedmaster is another person that thinks this block has possibilies because of the less restrictive exhaust flow. The good news is, it should be competitive and that adds another engine option to the class. Remember we do allow you to alter the tuner. You could? find that that the SST60 short tuner changes the performance of this powerhead. It should increase performance at the high end of the rpm range with the oval port. On the other hand you may find that a slighly longer tuner works better on the SST60 powerhead because you lost a lot of torque when you reduced the compression. Racers don't like some classes because they cannot tinker with their motors. In T you can tinker and have something a little different to the others. Your just tinking in other areas other than the powerhead. ALL GOOD NEWS!

Questions and Answers

[1] What steering cable should I use. The small coated cable saves the pulleys.
[2] I got a used cleaver prop for my stinger. It doesn't fit with the thrust washer. Is it OK to run without a thrust washer?

[1] Use aircraft cable . Grease the cable near the pulleys. You can also get stainless cable. Don't use the small diameter coated cable you see on the small hydros.
[2] The original OMC props ran without a thrust washer. The prop rests on the SMALL ramp on the prop shaft. Problem is over time that end of the prop will enlarge and prop will slide over that shoulder and destroy the seal and carrier. I suggest you run a thrust washer. It is easy to grind it to the small diameter of the prop. Some use a locking bolt instead of the original bolt because they can't put the pin thru the prop shaft. I normally just cut the slot deeper in the bolt and use a smaller pin. I have never lost a prop or damaged the case. I know of many you have lost props using the lock nut.

Questions and Answers
[1] I tried to test an OMC cleaver on my Yamaha, it was the correct spline, but it was too long and I couldn't get the prop shaft pin in. I didn't want to grind on the prop and have to buy it before trying it. Any ideas?
[2] I like the new Tuff Critchfield. Will it be race ready out of the mold?
[3] Is Scott Whittington looking for a 15 foot Viper when he is is Florida?

[1] First it is best to test before you buy, unless the prop is so cheap that you know it will need to be reworked anyway. I have tested lots of OMC props on our yamahas. I honestly have never found one that worked as good as the Mercury thru hub cleavers. I cannot explain why, but the Mercury props work very well on the small Yamaha gearcase. Anyway that is just my opinion. To fit the OMC props on, I use the new style yamaha thrust washer. You can grind it down so the front portion fits in the back of the OMC prop. Most times that allows me to get the prop nut and pin to fit. IF? the prop is still too long I use a spacer between the prop and the pin. Then a use a thin locking nut tightened against the pin.

[2] Mark can answer this better than I. I have two boats out of those same molds. Unless Mark fixed the molds, the owner will still need to work on the bottom to remove the hook, straighten and sharpen edges same as the rest of us.

[3] Scott is going to Florida. I haven't found a SUITABLE [good and realistic priced] Viper or a 15R Allison yet for him to go and look at. We will let you know. I do want to see a 15 footer in T850.