Author Topic: Nitrous  (Read 1996 times)

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Offline afkrejci90

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Nitrous
« on: November 21, 2013, 03:13:29 PM »
So I'm wondering what is needed besides what I already have to use a NO2 setup for trips to the track.  Forged pistons and Carrillo rods I already have, along with an APE lightened crank, is there anything more that I would need to strengthen the bottom end?  Will the CB750 even hold up with NO2?
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Offline Sam Green Racing

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Re: Nitrous
« Reply #1 on: November 21, 2013, 04:09:36 PM »
I don't see why not when you consider what has been pumped into them in the past.
It's not going to last as long as a motor on just gas but who knows how long?
It's normally the top end that takes the bunt of it from what I've heard.
Start with low % ages.

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Offline afkrejci90

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Re: Nitrous
« Reply #2 on: November 21, 2013, 04:23:32 PM »
It's mainly going to be street with the occasional trip to the track each year, so the amount of abuse will be kept a minimum.
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'80 CB750C - Sold
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Nitrous
« Reply #3 on: November 21, 2013, 04:54:57 PM »
What size pistons?

How about top and bottom end studs.
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Offline BLUE71TURBO

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Re: Nitrous
« Reply #4 on: November 21, 2013, 08:10:29 PM »
 Don't forget real good valve springs and heavy duty case and cylinder studs. Also you will need to run a copper cylinder head gasket along with having your cylinders " O " ringed with copper wire. Nitrous Oxide can be real fun but any disruption in the delivery of the fuel " gas " side of the system will create a melt down bomb between yer legs.   :o  Special filters are needed for both sides of the system so that the solenoids super small orifice's don't get plugged.   ;)
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Offline afkrejci90

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Re: Nitrous
« Reply #5 on: November 21, 2013, 10:54:49 PM »
72mm pistons with the APE studs.  The head will have the works, springs, valves, etc.  Do you have anymore info about the copper wire "o-ring" I've never heard of this before.
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Offline dragracer

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Re: Nitrous
« Reply #6 on: November 22, 2013, 12:16:33 AM »
72mm pistons with the APE studs.  The head will have the works, springs, valves, etc.  Do you have anymore info about the copper wire "o-ring" I've never heard of this before.

Basically a shallow grove is cut around the circumferance of the top of the liner in the cylinder. A thin wire, steel or copper is inserted in this grove. When the head gasket(copper) is torqued down, it bites into the o-ring to form a tight seal around each cylinder to keep compression from leaking past under extreme cylinder loading from boost or nitrous. I think many have success with the MLS gaskets these days versus o-ringing or copper head gaskets. Personally. i'll stick with the tried and true o-ring methods. When i see  the car guys all go to MLS, i might change my mind.

Offline afkrejci90

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Re: Nitrous
« Reply #7 on: November 22, 2013, 03:31:58 PM »
I wonder if anyone around chicago can do that, seeing there's basically no one around here that has no machinery to work on these small engines, but maybe APE?
'78 CB750K http://forums.sohc4.net/index.php?topic=105327.0
'80 CB750C - Sold
'06 CBR600RR

Offline joe p

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Re: Nitrous
« Reply #8 on: November 22, 2013, 03:35:05 PM »
Fast by Gust did all my work.

Offline MRieck

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Re: Nitrous
« Reply #9 on: November 22, 2013, 03:43:47 PM »
72mm pistons....how large a shot are you going to use? 20 jets on the nitrous side? It will be tough on the primary chains. Are you going to use a progressive feed box?
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Offline afkrejci90

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Re: Nitrous
« Reply #10 on: November 22, 2013, 06:45:57 PM »
I'm going to keep it down to a small shot to begin with.  There's already going to be a big performance increase just from the big bore and other mods.  This is just to push that envelope a little further  ;D  I guess it wouldn't hurt to run a feed box.
« Last Edit: November 22, 2013, 06:48:37 PM by afkrejci90 »
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'06 CBR600RR

Offline dragracer

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Re: Nitrous
« Reply #11 on: November 22, 2013, 06:48:26 PM »
72mm pistons....how large a shot are you going to use? 20 jets on the nitrous side? It will be tough on the primary chains. Are you going to use a progressive feed box?

Ouch, using 20 on the nitrous side with the traditional 4 spread makes it 24 on the fuel side. Damn, thats over a 50 horse shot.

Offline MRieck

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Re: Nitrous
« Reply #12 on: November 23, 2013, 07:25:09 AM »
72mm pistons....how large a shot are you going to use? 20 jets on the nitrous side? It will be tough on the primary chains. Are you going to use a progressive feed box?

Ouch, using 20 on the nitrous side with the traditional 4 spread makes it 24 on the fuel side. Damn, thats over a 50 horse shot.
That's what I used on my FJ Frank....no progressive box. I broke some clutch parts.
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