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The only reason I'd run race gas is cause Dok loves the smell of it...figure I might as well give him something to smile about while he follows me around the course!

Hey Paul
I posted a reply to this yesterday and it got lost in cyber-space?

Compression checks have many flaws, they vary for many reasons such as exhaust port height, ring seal, ring gap, cranking speed, compression reliefs, cylinder wetness, cylinder temp, etc. A true hi-performance 2 stroke actually has a lower compression than stock due to the super charging effect of the tuned exhaust.
Fuel however, is a field leveler. No matter what engine you have and no matter what "Effective" compression you have, a given fuel will limit and restrict what you are running.
Example; A raised exhaust port and appropriate megaphone will show a lower compression reading yet actually have more effective compression than stock. You won't get away with this added compression if you are restricted to pump fuel, everything else being equal.

That being said, I am still comfortable with just a simple compression check. Someone having to supply fuel at a race is more trouble than it's worth, at least at this stage.

Cool. agreed, securing supplied fuel is just another task we don't need on race day. I realize some of the simple tests are flawed just trying to keep things simple and some what effective for race day. I go to the races to shoot the shit and run a few laps, I don't want to spend alot of time filing out forms and standing around for tech inspection, we have enough problems getting our boats in the water timely, so simple is essential to me, cause guys also need to make time to help set up and organize the days racing and not just worry about their class.

I'm going to be a newbie with you guys but I figured I'd put my thoughts in anyway for the engine rules if it were up to me

- I like the 160 PSI COMPRESSION RULE. If you're raising the exhaust ports, it just means taking a little more off the head. I'm guessing we need this just to keep speed down enough not to have safety cells. I don't know what the decompression holes look like on the other blocks that will give a false reading but maybe they should be plugged if possible or have a max compression for those engines?

- ALLOWED TO USE BILLET HEADS - like what are being made by Gieger who I have yet to meet, would be great for having different chamber sizes to play around with to hit your 160psi compression for whatever port work you do without having to have a whole bunch of milled heads or having to keep replacing head gaskets every time you pull it apart. I'm guessing they are O-ring design. Would be nice to run them. I don't really see it having much advantage in performance over others that aren't using it. It just makes things easier. (and it looks cool!)

-ALLOWED TO MODIFY PARTS THAT CAME ON THE ENGINE FROM WHICH THE ENGINE BLOCK IS BEING USED OR USING PARTS FROM THE SAME MANUFACTURER THAT DIRECTLY BOLT UP - running sst-60 style carbs on an engine that didn't come with them, running a stinger short mid or cutting one down and nitro gear case on a 56'er that never came with one originally. Lighting up flywheels, porting and polishing, adding finger ports to the pistons, using different tuners or modifying the one you have all fall into that.

-POWER TRIM OF ANY TYPE ALLOWED - so you can run a yamaha or merc on an OMC or fab something up

-NO FUEL INJECTION ALLOWED UNLESS THE ENGINE ORIGINALLY CAME WITH IT

-60CI MAX

-STOCK BORE AND STROKE FOR THE BLOCK YOU CHOOSE TO USE (up to .040" overbore allowed)

-PUMP FUEL ONLY

I think being allowed to mix and match parts from other manufactures will scare new racers as it just makes things more complicated and will end up costing large $ for people who aren't going to do their own fab work. It may help in the short term for lower units as a nitro gear case can cost good money and are hard to find but once people find the perfect lower unit (maybe a 30hp Yamaha or whatever) that part is going to end up being expensive and hard to find as well. It also takes the fun out of having a battle between engine brands.

Inspection would be easy - just check for stock bore and stroke. Stroke wouldn't even require the head to be pulled off and if you were to check the bore with an o-ring head, that would be no big deal either. Everything else would be a quick visual of the engine.

Just my 2 cents

Kevin

T MEETING - to reach consensus, OR agree to disagree

I have asked several T racers to meet F2F Sunday, 3pm @ TIBS, to discuss technical options, spec for the class. For the most part discussion will revolve around themes presented at top of this thread, and a few others. I will not post participant names, they can ID themselves. I want to emphasize all SO/T racers are welcome to join us and participate. This is your class.
This thread has prompted a great(civil) discussion. There will remain differences of opinion, but there is MUCH common ground.
The objective Sunday is for participants to find that common ground, establish consensus for proposed changes, hash out details NOW, prepare draft language to be presented at CBF SO meeting.
This is a pro-active approach, rather than waste time at CBF discussing minutia in circles, in a time restricted format.
Whatever suggestions bubble up Sunday, are widely accepted, I suggest be posted here for further review, scrutiny, justification.
Some ideas proposed Sunday will not gain wide acceptance. These can still be proposed or amended at CBF meeting by anyone who is compelled to do so, & is encouraged.
My own approach is one of moderate change, maintain class integrity, safety and scrutiny. If by the end of 2013 we have not made sufficient progress, we revisit in 12mo. My focus is to maintain class accessibility for new entries, promote growth of a larger base to ensure longevity, encourage and coach driving skill rather than technical wizardry. Reflect on larger aspects of class growth, rather than technical/mechanical extremes to which you are prepared to go to get an edge. I am one vote, support progress for the class.
ALL proposals brought forward at CBF meeting Feb 23, will be put to vote, either accepted or declined, majority rules.
As previously mentioned, all current CBF members are eligible to present new rules or amendments to current rules, with ONE PRE-CONDITION: YOU MUST BE CURRENT CBF MEMBER FOR THE RIGHT TO VOTE, HAVE YOUR SAY.
I am not driving any specific rule changes, will not take the lead to record or submit rule change proposals. I am pleased to facilitate individual racers coming together as a group, a team.
Thoughts to share? Do so here or contact me directly.
Cheers

Can we pass a rule that Luksep needs to keep his pants on at the race site...he's scaring away potential racers!

short and simple example from APBA
http://www.apba.org/superlight-tunnels/
Experimental
Experimental Class (X-Class) is for those boats that do not comply with the Superlight Tunnel Engine Technical Rules.
Engines: Shall not exceed 1000cc's and have shiftable gearcase (forward, neutral, reverse), tiller arm, and use pump gas only.
Minimum Ages:
Driver - 17
Co-Driver- 14

If the goal of the changes is to:
- limit tech inspections to a simple 160 compression test
- allow modified and or custom made parts including billet heads
- allow mixed motor manufacturer's parts
- allow custom porting
- allow larger carberators compared to the original stock carbs.
- modiflying . replacing and/or machining of stock parts example flywheels, cylinder head chambers etc.
- 60 cubic inch motors
- reduce cost to build motors
- increase class membership
- maintain current performance levels
- avoid any changes in boat specs such as weight increase and manitory safety cells.
- avoid Stock Outboard members from forcing T850 out of SO into OPC

You only have one choice to decide on.

Can you write the rules to make this happen with no inspections other than a compression test?
OR
Go Mod with no inspections other than a safety inspection and a compression check.

Steve, I wonder why you have not seen any V6 3 cylinder convented motors in this class. You may recall that happened in SST70 . Guys took a 140 cu inch Mercury V6 and convented it to run on 3 cylinders instead of 6 thus giving them the 70 cubic inch. I have a broken 2 liter Mercury Champ motor which would be perfect. I think I better keep it for T850 to run on a 15 foot Viper.

I would suspect that the 1/2 a v6 would be too heavy for a slt as it would be for a 13ft t-boat.

Time to get building Don, I will be curious how it handles in the corners with all the weight on a Viper. Although it is lighter then a traditional v6 it's still heavy relative to a traditional 3 cylinder. What gear case would you run? Counter rotating to match rotation of crank?