Landracing Forum
East Coast Timing Association => ECTA Rules Questions => Topic started by: racer x on May 03, 2010, 02:41:19 PM
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I am building another gas tank for my bike. I run only in Modified class both fuel and gas. The rule 7.F says 1.32 gallons capacity. Can I put a partition in the tank with two fill and two outlets?The total capacity being 1.32 gallons for both sides.
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Well, I'm not sure I understand the question, but I'll take a whack at it anyway. If the two tanks' total capacity is less than 5 liters (1.32 gallons) you're in altered a/k/a special construction, because to be in modified you need a tank at or larger than that capacity. Altered allows ANY size tank.
But why a partitioned tank? What's left unsaid here?
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Well, I'm not sure I understand the question, but I'll take a whack at it anyway. If the two tanks' total capacity is less than 5 liters (1.32 gallons) you're in altered a/k/a special construction, because to be in modified you need a tank at or larger than that capacity. Altered allows ANY size tank.
But why a partitioned tank? What's left unsaid here?
Hi Jon.
I want the two tanks total capacity to be over 1.32. I may build it 1.5 gallons to be safe.
.After thinking about it I could just make my main tank 1.32 .Then a second tank of what ever size fits .But size is why I want to put it in one tank.I do not want to run in the altered class .
I will remove the Nitrous to run in the GAS class.
The reason for the separation is I was thinking of using two fuels. For the carbs I run 100 octane rocket brand. Then I want to run 118 octane fuel with nitrous .
I don't think the engine will run well on 118 octane and I only want to spray 6th gear. I figure the 118 will cool thing down so I can run more timing.
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If I read this right -- and I'll make sure I'm doing just that -- the capacity of the two tanks, added together, is grater than the 1.32 gallons, right?
If that's the case -- you'll be in altered/special construction class. The idea of the tank minimum size rule is to make the bikes in modified class be somewhat related to a street-legal bike, whereas a bike with a tiny gas tank (in this case, about 2 1/2 liters or less than 3 quarts) is a race-only bike.
And now that you've publicly told us that you want to put fuel for one class in one side, fuel for a different class in the other -- nope, I don't think so. I'm willing to let the powers that be (read: Race Director or Chief Inspector) override me if they choose to interpret the rule in a different way. Chances are that if you arrived at the race track without having asked first here -- and you told me what you wanted to do/had already done -- then I'd likely go asking a higher authority to make the ruling.
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That is why I ask questions before I build. :-D
I only want to run in Modified or Modified Partial streamliner . If I enter in the gas Class.I would show up with both tanks empty. Then buy gas from the track and seal the tanks. MPS/G 250-4
If I want to run Modified Partial streamliner. But in the fuel class. I still buy fuel from the track .But I would buy 2 different octaine levels . Not seal the tank and hang a nitrous bottle on the side .MPS/F 250-4.
See
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having a hard time following the logic....
per sss...
"""If the two tanks' total capacity is less than 5 liters (1.32 gallons) you're in altered a/k/a special construction"""
followed by (per sss)....
"""the capacity of the two tanks, added together, is grater than the 1.32 gallons, right?
If that's the case -- you'll be in altered/special construction class"""
Joe :)
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I want the two tanks total to be MORE that 1.32 gallons. But want to stay in Modified . The rule 7.F says
Gas tank"S" If not original equipment to the production model.Must have a minimum capacity of 5 liters or 1.32 gallons
So if I build one 1.5 gallon tank with a divider . Fill it with track fuel and sealed it at the track it should be in the GAS class . And if it is not sealed it is in FUEL class.
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having a hard time following the logic....
per sss...
"""If the two tanks' total capacity is less than 5 liters (1.32 gallons) you're in altered a/k/a special construction"""
followed by (per sss)....
"""the capacity of the two tanks, added together, is grater than the 1.32 gallons, right?
If that's the case -- you'll be in altered/special construction class"""
Joe :)
You are saying I will be in altered either way?
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Hey......when was the last time you saw SCTA/BNI (Tom Evans and crew) check the capacity of a fuel tank.......Hey.......SSS, how many times have you checked tank capacity while doing Tech.... Hey....How many times did they check tank capacity in impound after a record was set.......Stupid rule................
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Okay -- what I meant to say is that the rule wants tanks under 1.32 gallons for altered only, but any size is okay. For modified it says tanks must be at least 1.32 gallons.
As for measuring how much they hold -- Bob, I have checked capacity while doing tech when, for instance, I've had the racer open the tank -- which was obviously questionable under the rule -- and then further saw that he had altered the innards of the tank to further skirt around the intention of the rule. I check by following the racer to the fuel station and watch as the tank is filled. For impound -- I don't work impound at SCTA/BNI events, so can't comment on how often it's done at one of those events, but I know that tanks at Maxton won't make it to imound if they're questionable -- because they'll have been checked during inspection.
If you feel the rule is stupid -- as usual, consider submitting a rule change form.
Racer X -- as far as the way the word "tank" is shown as plural -- I will assume that the writer of the rule did not imply that multiple tanks would be installed, but rather used the plural to imply "tanks on all bikes" rather than the multiple tanks on one bike. Here's a good instance where I'd buck up to a higher level of official for a ruling.
Is that a little more clear? I sure hope so. Busy day at the store -- that's my story. . .
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I don't care if they check the capacity or not.I want to make sure I follow all the rules .I don't even want to bend the rules.That is not what I was implying with the emphasis on the S .I was just pointing it out .
I just want to go fast. And do it in the Modified category.
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racerx, its easy and best to get confirmation from
scta tech.....
my opinion is that you are carrying or have the capacity to carry more than 1.32 gallons of
fuel.......no matter how many reserviors......so ok for modified.....:)
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edit....
Joe :)
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I would like to be legal everywhere .But I am mainly concerned with ECTA rules .
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Just curious, you mentioned only doing the shot in 6th with the 118 and that the bike wouldn't run very well on the 118 alone, thus the desire to carry two fuels. Are you planning to switchover tanks during a run or is the low octane just for use while heading to staging?
I am going nuts trying to think of a way you could safely switch supplies on the fly so I am guessing this may be a way to make runs with and without nitrous that doesn't require swapping or draining the tank. :roll:
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Hey Milton. You bike looks good. I cant wait to here it .
My thinking is and that is all it is at this stage. ( I do have an oil containment pan ordered mind you)
My plan is to run slightly lower compression than I am now Say 12 to1.The 100 octane from one side of the tank goes into the carbs .The bike runs great and with a lot of timing advance it will make lots of power (for 249cc) .
Then from the other side of the tank to an electric fuel pump I will feed 118 octane fuel. that will go in with the nitrous . 15 /18 jets and cool things down. At the same time I will move the timing back enough to keep it from having problems. :-P
Don't have specific numbers yet .But I am starting with the tank for a better aero position and building the rest as I can. That is why I want to still run in the gas class.
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racerx, its easy and best to get confirmation from
scta tech.....
my opinion is that you are carrying or have the capacity to carry more than 1.32 gallons of
fuel.......no matter how many reserviors......so ok for modified.....:)
IS that the answer? as long as I have the capacity to carry more than 5 liters of fuel it is OK for modified.No matter how many tanks or reservoirs are on the bike.
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I'll ask for the "higher up" folks to give an opinion. gotta call one of them today anyway -- will see if 1.32 g is total onboard capacity or per-tank capacity -- and put you to rest either way. Thanks for the perseverance.
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I'll ask for the "higher up" folks to give an opinion. gotta call one of them today anyway -- will see if 1.32 g is total onboard capacity or per-tank capacity -- and put you to rest either way. Thanks for the perseverance.
I asked Deb to ask Todd. I hate to be to persistent .But I need to get the desine finalized.
I could make the tank 1.32 gallons feeding the carbs.Then another .5 to feed the nitrous. Packaging is everything on a little bike is critical.
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may want to rethink the premise...
if your running on the lower octane thru carbs
all the time, and then always have the 118 as
fuel enrichment with nitrous....your net
octane that the cylinder is seeing may be
woefully inadequate........
ie..you will have cylinder pressure that will find the
weakest link in the hydrocarbon chains present.....
just be careful...
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I doubt if anyone cares if you have more than one fuel source. It would be considered one tank no matter how you split it up. If you had a stock tank with a separate holding tank for the other fuel I don't see any difference as long as it conforms to the safety rules.
As far as running different fuel for nitrous, is there some fact here or are you guessing. Octane is a measure of anti-knock only. The amount of heat in the fuel is a whole different thing. Two different fuels with the same octane rating can be very different.
ERC 110K has an octane rating of 115 and a heat release per unit rate of 19,800
ERC A-8C has an octane rating of 120 and a heat release per unit rate of 19,683
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I got distracted and the post I started to write -- didn't get posted. So, delays notwithstanding, here's further comment -- from someone with more whiskers than I (at least when it comes to ECTA rules):
If both (or all) fuel tanks are completely plumbed -- petcock, hose, fuel pump, filler cap, etc -- and the total capacity of the entire group is more than 1.32 gallons -- the bike may run in the Modified class. The modified rule says fuel tanks must be at least 1.32 gallons capacity.
Dean's got a good point, and I'll further it -- at Maxton, with the run time being so short -- is there time for the fuel switchover to happen completely? Say you make the switch at half-track. You'll be in the lights within 20 seconds or so (considering your probably speed) -- so will the fuel line from the switchover point to the carbs/injector rail exhaust the first type of fuel and get completely over to the second type -- in time?
However - - the answer to the question is that I was in error -- total fuel capacity on board is what will be considered for this item.
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Eric, I would reconsider using two fuels. One fuel and N2O should achieve your desired result,,, mixing the deal may give you an undesirable ... boom...
Be careful my Friend,
Charles
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Eric, I would reconsider using two fuels. One fuel and N2O should achieve your desired result,,, mixing the deal may give you an undesirable ... boom...
Be careful my Friend,
Charles
I am trying to be a careful as I can be.But I am in uncharted territory. Not much hard data on modifying the 250 ninja for real. Jon and Mike have done some with the turbo but I am using a different engine and a different approach.And doing it myself . So any help or advice will be greatly appreciated.I am learning as I go
From the beginning. The 249 cc four stroke engine makes 26 hp stock .It is different from the previous engine because it uses shim under bucket valve train . The old engine used rocker arms.
For the last three years I have tweaked the engine to 33.7 hp (last good dyno run.) Most of the power comes from feeding it lots of fuel and advancing the timing . I got 1 hp just from not tapering the timing off at High RPM . I also have forged pistons and other good stuff.
I have a programmable ignition system with two ignition maps that can be switched with a simple open or closed circuit.My plan is to run 45 deg on map 1 then when I push the nitrous button a relay will switch to map 2 and that map will have 42 deg or so.
I found from dyno testing that 45 deg of advance works best and I use Rocket 100 all the time.
I have not tried running 118 but I GUESS it would loose power If I ran that fuel .I may be wrong there.
I have a thick copper head gasket to lower the compression" some "for the nitrous . But that would make running 118 all the time worse.
I was told to use high octane fuel with nitrous to cool the charge . That way I can get away with more timing advance than otherwise.
Maybe I should can use rocket 100 with the nitrous and It will be OK . That I don't know . My thinking is "somemore " Octane when spraying nitrous would help guard against Knock
As far as switching things during a run .I don't need to switch anything on the run.Fuel runs from the tank to the carbs like normal.Then when I energize the nitrous system .Fuel will be delivered to the solenoids from the electric fuel pump.The solenoids will open with a thumb button and a WOT switch
I run a 1/4 mile in 14 sec .4th gear at 90 mph .I only go 110 in the mile. So I am in 6th gear at the 1/2 mile. I will just spray from the 3/4 mile marker on . That is a 7 second shot. I could spray from the 1/2 mile but that would be for later .(Like Sunday afternoon in October) haha
I will have to start another thread about jetting and pump and bottle pressure for 10 hp on a 15 cubic engine.
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Bottle pressure is usually around 900-1100 psi no matter how much you're dosing the engine. The jets are set for that pressure, so to speak. If you've got a tiny bottle you might run into problems with the pressure sagging as the contents are used, but spraying 10 isn't much -- so it'd have to be a tiny bottle for you to suffer much sag. We use a 10# bottle on my 1340 cc bike -- but for two reasons. First of all -- it's got to spray for about 45-50 seconds on the long course at Bonneville, and second because we use the nitrous to actuate the air shifter, too. That last item doesn't use much, but we don't want to have any issue - nor a need for a bottle warmer under normal conditions.
Back to dual tanks -- both are plumbed to the engine, right, and you theoretically could change tanks on the fly, right? Is the system gravity feed or is the fuel driven by a pump.
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I have not built anything yet . But no only one side of the tank would be plumbed to the carbs. Then the other side would go to a fuel pump.Before I got the idea to use two fuels .I was going to remove the gas gauge sender and put a 1/4 inch fuel nipple in a plate and cover the hole where the level sender was. But my tank is to wide .So I need to build a new tank anyway.
As for my GUESS. I was going to use 7.5 psi of fuel pressure through a 18 fuel jet.And with 1000psi of nitrous in a 2.5 lb bottle I would regulate it to 900 psi and spray that through a.15 nitrous jet. I would make the fuel line shorter than the nitrous to make the system go rich at first . Dose that work at reducing shock to the bottom end?
I think I will have enough pressure to last 7 to 10 seconds
Also about fuel lines. Some Kits have braided steel fuel line.I like that but again packaging is everything.Can I use that clear red and blue line that comes with some cheaper kits.It will fit better .But I like the steel lines better.
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Racerx, I like what you are “thinking/doing”. Remember that when you spray you are only going to add enough fuel to offset the ~18 HP gain. You will be mixing the 2 fuels at a about a 2:1 ratio, so your octane will be lower than the 118. BTW, the effects of “cooling” are more felt with Nitrous than the fuel.
A 2 ½# bottle will be just fine with that small of spray especially if you regulate it to 900 psi. When I was running a Nitrous bike, I used two 28 jets with a 2 ½ bottle (dry shot). I had it regulated to 850 psi, but I heated the bottle to 1250 psi. Spraying only 6th gear, the bottle psi would drop to right above 850 psi. 5th and 6th, the pressure would drop to the high upper-700s.
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Thanks Encouragement is a big help.
I don't think I can get 18 hp from nitrous But that is what I need. It will be fun trying.
So maybe I should just go with a single tank and have two outlets one fill cap and run 110 octane fuel for both the carbs and the pump?
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I'm not a serious bike guy, only having owned a couple of Honda 350 Four's.
but for the switch between octanes, why not have 2 different tanks, same shape, or not; with the 2 different octanes. Just switching tanks? use one for each class, would be included in the class change inspection?
Out of the box?
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The reason for using two fuels is to get a little more octane when spraying nitrous. I don't want to run hi octane with low compression because it may cost me power .I only have 30 hp to work with.If I lose 3 hp that is 10 %
.My concern is this
If the total of both tanks is 5 liter . 2.5 per side .But when I run in the gas class I only have half in use .The other side is empty and sealed .Is that tank still legal for modified class?
It could be thought of at that point as a 2.5 liter tank with a 2.5 liter cavity welded to it. My concern arises from people putting things inside there tank to lower capacity allowing them to run in altered. I don't want to be an altered.
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RX, The bottle pressure will decrease as you spray, no matter what you do unless you back pressure it with nitrogen. That happens because the bottle gets cold when the pressure is released, and colder is less pressure. If you start you bottle cold, the pressure will not change much until the N20 starts to run out. You should be able to get at least 3 lbs in your bottle if you keep it cool. How many 15 jets are you planning to run? Run a lb of N20 through your system and time it. Using the correct mixture 2 lbs per minute should be about 20 hp. Run it a tad rich.
You can search the site for N20 and look at suggestions. I recommend before you spray anything in your engine you figure out what you are putting in there. Without flowing your jets you will not know what you are putting in your engine.
We ran ERC 110k as motor and enrichment fuel with no problem.
Good luck with your project
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One jet for each cylinder .I arrived at that 15 number by looking at the available jets that is the smallest that comes with a 10-100 hp kit ( I have not bought anything yet)But 10-15 hp is all I can expect from a small engine . I "think " A 2.5 lb bottle will hold for an under 10sec. spray. As it looses pressure it will sent the mixture rich.That is OK
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.... But 10-15 hp is all I can expect from a small engine . I "think " A 2.5 lb bottle will hold for an under 10sec. spray. As it looses pressure it will sent the mixture rich.That is OK
If you have 33, and then dropped compression, you can probably get to 50+ with the N20, is the bottom end up to 20 more HP.
Run the system outside the motor... then you will know what you are adding. Old rule of thumb... 1 lb per minute is 10 HP... if you use 2 lb in 20 seconds you are probably adding 60 HP... a little much for your motor to start....
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I don"t think the bottom end will hold up long at 50 hp but I will find out.
Part of why I only want to spray the top gear is to reduce load to the bottom end.
I do appreciate the advice on testing out side the engine.
I am going to start another thread about nitrous on a 15 ci engine.This thread is about the legality of the tank. :cheers: