nofxpunk_541

i am in the process of rebuilding my 12a, i was just wondering, what would i have to do to make it be able to withstand a little bit of N20...i am already putting on 3mm carbon apex seals, but i dont know if there is anything else i should do, i just figured i would do it now, while the engine is mostly taken apart...

12abridgeport

Actually if you are planning on running NOS you should use factory seals. You can still run like a 50-100 shot on carbons but very easy to break them and make sure you have MSD boxes. Personally i wouldn't run more than a 50 shot with carbons.

REVHED

Carbon seals and N20 are not a good combination.

79+80+84_rx-7

thats what i was thinking........


NOT GOOD!

Grammaticus

If you look at the materials and the things that you want to accomplish you are faced with a few undeniable facts:

The factory apex seals (Steel) are fairly good for a low revving motor (the thing about carbon fibre apex seals is that they are designed for higher revs and won't seal well at idle or under 8,000 RPM.

Maybe i'm getting ahead of myself, If you are going to run the carbon seals, the car would have to be designed for a higher revving environment. At 8,000 RPM you are most likely looking at either a very large streetport or a bridge port (probably the latter as they are desinged to flow upto and over 13,000 RPM ((after that it's a peripheral port)).

To achieve a High redline in a rotary engine, you'd want to make the rotating mass (rotors, flywheel, clutch, eccentirc shaft and counterweights) as light as possible.

Now, combine a very light rotating mass, with fairly flimsy apex seals (those would be the carbon ones that tend to "chatter" (meaning they bounce off the rotor housing and back into the rotor, stressing the springs and corner plugs) and add in N2O.

Looking at the effects of N2O (Nitrous Oxide) we gather that it increases horsepower by modifying the air temperature (N2O is kept under pressure and there for is cold, colder air = denser air, denser air = more oxygen, more oxygen = bigger bang, bigger bang = more horsepower) N2O also contains an extra Oxygen Molecule (1 Part Nitrogen + 2 Parts Oxygen = N2O) this new compound injected into the ari/fuel mixture creates even more oxygen for the gas to burn off of.

The result of N2O, is a brighter HOTTER flame in the explosion. Steel adjust well to heat change, it is designed to. Carbon Fibre on the other hand tends to get brittle. Granted we aren't dealing with the OMG A-PILLAR MOD RICER FAN BOY carbon fibre, but the fundamentals of the two materials are fairly similar. Heat = Bad.

So, after learning all that, we can come to the following conclusions:

. Carbon fibre Breaks down in heat
. N2O Makes the explosion hotter
. Carbon fibre seals poorly at low RPM
. N2O should be staged at the beggining of the power band (IE. Low RPM).
. Carbon fibre seals are used in low rotational mass engines
. N2O pushes the engine harder at higher RPM, so you get a light mass being stressed to hit high RPM for the seals to begin working effectivly, then hitting it with a N2O burst which would increase RPM alot more than a normal application (because the force required to move a lighter mass is obviously less).

all in all, as was stated above, Nitrous in this case would be a bad, bad bad idea.

Rethink the end result, before blowing money on things that will just force you to re-build faster.

But then again, I am kind of new to this so I might be completely wrong...

cheers'

79+80+84_rx-7

LMAO!

fatboy7

Carbon seals aren't carbon fiber.... they're some sort of carbonized metal.

snake eyes<l><l>

personally i would rather have a port, it'll be about the same over time cause u lose mpg but you're paying for more N2O, so it would even out

jmho

Snake Eyes<l><l>

vipernicus42

iTrader: (4)

Am I the only one who noticed that he said N20 was made of :
1 part nitrogen and 2 parts oxygen?!?

Geez.. I mean I'm not done college yet, but Mr. Blaine's 11th grade chemistry class said that in a chemical formula, the subscript number directly AFTER the element's symbol denotes it's molar ratio

In English

N2O = N2 + O
or 2 parts nitrogen and 1 part oxygen

alright, I'm done my nerdy nitpicking, it seems Grammaticus should have spent less time studying English, and more time in Chemistry

good write up on the carbon apex seals though :P

Jon

nofxpunk_541

alright, so if I stick with the stock seals, what am i going to need to do?

Stepdaddy

nos on any engine is a hard change

12abridgeport

It's all depends on what kind of fuel supply you already have and how much nitrous you want to push. The safest and best way of course would be to use the wet kit that has a fuel solenoid. Basically for a certain ammount of nitrous you want to add a certain amound more fuel.

REVHED

Eh? Carbon seals are used for the very fact that they don't chatter at high rpm like the steal seals do.

12abridgeport

I used factory seals in my bridgeport and of course i reved the living hell out of it, the motor started loosing compression big time. I'm rebuilding it right now and will be using carbons this time. I was planning on pushing nitrous that's why i went with factory ones in the first place.

nofxpunk_541

what is streetport and bridgepost? i hear everyone talking about it, i just dont know what it is, sorry...i am kinda new to the rotary world...but learning fast

Grammaticus

A street port is an extended intake port, a bridge port is the addition of a second hole on the intake side of the intermediate housing. Google search it, you will win.

The statement made about N2O + Carbon seals at a high RPM was made not that the seals would chatter at a high speed but would need to be at a high rpm 8k plus to seal well enough to stand a N2O shot.

cheers'

jimmyrose99

nope i noticed too lol

REVHED

Carbon seals incompatibility with nitrous has nothing to do with sealing. It's because they don't tend to handle detonation and the extra stress nitrous (or forced induction) can place on them.

Who said carbon seals don't seal well below 8000rpm anyway? Just because they seal better above 8000rpm than steal seals doesn't mean they seal poorly below. It's mainly during starting and idle speeds that they might cause any problems.