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Old 10-25-2001, 12:32 PM   #1
adeck
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Location: Branchville, NJ USA
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2001 2.5RS
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Default Nitrous wet kit compression?

With any nitrous wet kit, say running a 55 shot how much would it affect your cylinder compression ratio?
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Old 10-25-2001, 01:02 PM   #2
Chuck_Beef
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The compression ratio stays the same...maybe your wondering how much more oxygen it's getting?
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Old 10-25-2001, 01:20 PM   #3
adeck
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I just thought that since your adding so much more air into your motor that it might raise compression, kinda like a turbo forces air in thefore creates a higher compression. The nitrous kits add more air therefor wouldn't they raise compression a tad?
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Old 10-25-2001, 01:51 PM   #4
HndaTch627
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nitrous will affect you overall combustion pressure...as far as affect compression ratio it does not(until you detonate). You still run 10.0:1 compression w/ nitrous it's just now there's more air and fuel being punished by the piston.

Jeremy
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Old 10-25-2001, 02:22 PM   #5
Eric SS
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swap and N20. gone. : (

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Compression ratio is something that is mechanically built into the engine. it cannot be changed by adding nitrous or boost.

Eric
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Old 10-25-2001, 02:23 PM   #6
HndaTch627
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imprezinator it can with a little detonation...if ya get my drift
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Old 10-25-2001, 02:36 PM   #7
Eric SS
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swap and N20. gone. : (

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lol.. I found that out the hard way! I now have much less compression in one of my cylinders than the others. I call this my specially designed dished piston.



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Old 10-25-2001, 02:41 PM   #8
HndaTch627
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LOL!!!
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Old 10-25-2001, 03:59 PM   #9
adeck
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What I meant to say is how will nitrous affect the cylinder pressure?
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Old 10-25-2001, 09:44 PM   #10
Eric SS
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It causes a lot more cylinder pressure because of the much bigger explosion. Not sure what ratio there is for finding out how much more cylinder pressure though

Eric
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Old 10-26-2001, 03:56 AM   #11
XT6Wagon
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Is your car Fuel injected? Well if it is, either use a **DRY** kit, or multi port kit, with a minimum of one per runner, each placed close to or after the injector. This is because the intake manifold WILL NOT flow fuel properly. So N20+ no fuel = boom.
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Old 10-26-2001, 07:55 AM   #12
adeck
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XT6Wagon, that is what I was thinking. I am looking at the ZEX kit, and I was wondering what the stock cylinder pressure is and how much a 55shot of N2O would raise it?
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Old 10-26-2001, 12:06 PM   #13
Chuck_Beef
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This is probably pretty inaccurate, but since it is a 55hp shot, take

(165+55)/165 = 1.33

so your engine is probably getting about 33% more oxygen with a 55 shot, which would cause a 33% bigger explosion
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Old 10-26-2001, 04:34 PM   #14
Iowannaski
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Um, if you are wondering how much higher the pressure will be at the top of the compression stroke with nitrous, it seems the answer would be lower. The pre-ignition pressure should be lower, assuming the amount of fuel and the oxygen/fuel ratio are kept constant. Because N20 is more oxygen rich than air, less gas will be present in the combustion chamber if the oxygen/fuel ratio is held constant.
Of course, this won't really answer your question because if you are planning on making significantly more power than stock you will also need more fuel in the combustion chamber. Gasoline, of course, does not compress at all, being a liquid as it is. This, in turn, decreases the amount of space available for gas under full compression, and would increase the preignition pressure.
Now, given all that, you should be more worried about melting your engine than increasing pre-ignition combustion chamber pressure.
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Old 10-26-2001, 09:54 PM   #15
Eric SS
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Location: 2013 335i, 2011 G37 coupe
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2000 2.5RS w/ EJ22T
swap and N20. gone. : (

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Wet systems are fine also... Been using em' for years without a problem, even on my scooby. I wasnt; running nitrous when the engine blew

Eric
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Old 10-27-2001, 02:33 AM   #16
HndaTch627
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i don't think i'd runa wet kit with the way our intake is designed, too much of a chance of puddling for my liking.

Jeremy
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Old 10-27-2001, 03:09 AM   #17
Eric SS
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Location: 2013 335i, 2011 G37 coupe
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2000 2.5RS w/ EJ22T
swap and N20. gone. : (

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I could go on and on about why I prefer a wet system over any dry system But I won't.. It sounds stupid but I am very tired of posting the same thing over and over after someone has a question like this Not trying to be an ass. To me, trying to convert someone that is a wet or dry user is like trying to convert an athiest or religous person.. It's not gonna happen. That being said, I actually took the time to search for previous threads of mine and came up with this one. it explains a little on the difference

http://i-club.com/forums/showthread....stem+injectors

Eric
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Old 10-27-2001, 03:12 AM   #18
HndaTch627
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oh no....i'm not arguing that, i think a wet system is the way to go, but i am a fogger guy....Hehe...when i build em wet i go big HP. MUHAHA!!! had a 250 bigshot on a truck i had....that was fuggin wicked. Well till i blew it up.

Jeremy
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Old 10-27-2001, 03:20 AM   #19
Eric SS
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Location: 2013 335i, 2011 G37 coupe
Vehicle:
2000 2.5RS w/ EJ22T
swap and N20. gone. : (

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lol.. Of course, If I could, I would fog the scooby! It actually has a good runner setup for a fogger!

Eric
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Old 10-27-2001, 03:40 AM   #20
HndaTch627
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yeah...it'd be awesome to put a fogger kit on a scooby.

Maybe i should build a nitrous powered scooby for someone.

Jeremy
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Old 10-27-2001, 03:58 AM   #21
Eric SS
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Member#: 1914
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Chapter/Region: SWIC
Location: 2013 335i, 2011 G37 coupe
Vehicle:
2000 2.5RS w/ EJ22T
swap and N20. gone. : (

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Try it. I bet with the right internals (i.e. forged everything, B&B) you could safely do a 200hp fogger kit

Eric
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Old 10-27-2001, 04:08 AM   #22
HndaTch627
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i am considering it now....dammit why did this have to go thru my head.


BAH!!!!!!!!!!!!!!!!!!

Jeremy
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Old 10-27-2001, 04:21 AM   #23
Eric SS
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Location: 2013 335i, 2011 G37 coupe
Vehicle:
2000 2.5RS w/ EJ22T
swap and N20. gone. : (

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I will be a notrous junkie till the day I die!



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