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Nitrous Oxide- safe for RX-7?

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Old 03-18-02 | 05:04 PM
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Nitrous Oxide- safe for RX-7?

I keep getting conflicting answers. Some say a Nitrous kit is disastrous to the rotary 13b, and some say it's fine. What's the deal? If I stick a 50hp shot in an NA, how much stress would I be putting in the car?

Another question:

If you use Nitrous, do you need to shift gears according to speed?

eg. I hit the button at 4th gear, this should take the car's speed to 5 gears or beyond, so, do I need to shift as I release the nitro?
Old 03-18-02 | 05:15 PM
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It's been said about a million times, nitrous works exactly the same on a rotary as it does on a piston engine. All the same rules apply. If you put a 50hp shot in the car, you'll be putting 50hp worth of stress on the car.
Do a search, there are probably hundreds of nitrous threads.
Old 03-18-02 | 06:16 PM
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The same rules apply:make sure you have the appropriate amount of fuel, your engine is in good shape, and you do not do it at every stop light, and you SHOULD be fine. www.fc3s.org reccomends that you use a "Wet" nitrous setup. Go to their website, click on "How To", then go to "Engine", then "Wet NOS". Enjoy, and don't blow yourself up!!
Old 03-18-02 | 08:31 PM
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Hey, i have done alot of research. A 50 shot will not harm the engine because it is not for long periods of time. But do make sure it is installed properly. Make sure it is a "wet" system. Make sure you have upgraded exhaust intake and ignition to play it safe. But whatever anyone else says, its not that bad on your car!

Evan
Old 03-18-02 | 09:21 PM
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I would go with the wet system and use one larger nozzle size than they recommend (run it a little rich).
-Eric
Old 03-19-02 | 12:03 AM
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I've spoken to Rob Golden of Pineapple Racing about NOS for N/A 13B's. What he told me is truly amazing. 13B should be able to handle 100 shot of N2O with no problem. But he did recommend that I get a fuel pump before trying it.

Jay Kim
Old 03-19-02 | 01:46 AM
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Originally posted by kim307
I've spoken to Rob Golden of Pineapple Racing about NOS for N/A 13B's. What he told me is truly amazing. 13B should be able to handle 100 shot of N2O with no problem. But he did recommend that I get a fuel pump before trying it
I'll guarantee you he was talking about a freshly rebuilt motor. Put a 100 shot in a 15yo 13B (or any motor that age) and I bet there'll be tears...
Old 03-19-02 | 01:49 AM
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I agree w/ NZ, as usual. Apex seals get brittle w/ age. I would not go over a 70 shot on an old engine.
Old 03-19-02 | 02:19 AM
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damnit, posted earlier but of course the server is a 386 SX with 256K of ram and my message didnt go through, anyways.

As long as you do not go past a 125hp shot you will be good. I ran this for a while on my 86 FC. If you want to go to a higher shot you will need some extensive internal engine work(better apex seals and blueprint and balance).
I ran 90-100 shot on a regular basis and never had a problem, even on that shot it was running rich. As for shifting, for a NOS newbie I would hit it at 4K in 3rd, after you get the feel of it you can get on the squeeze in second and bang through the gears on the spray.

DO NOT USE A LARGER FUEL JET THAN THE MANUFACTURER RECOMMENDED!!!
with the 100 shot it runs rich already, more fuel will lead to geting some excess nitrous and fuel/air mixture being expelled in the exhaust(BAD!).

Get an Air/Fuel ratio gauge before you do anything. I realize that you most likely dont plan on going above 75 HP shot, but this info is always good to know
Old 03-25-02 | 04:27 AM
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Maybe...since I told him that my motor only has 6k miles on it. Another thing, why is it so hard to put a turbo on N/A? Damn...it's easier to put turbo on a honda than the N/A rx-7 which has a turbo twin brother. Something wrong with this picture...

Jay Kim
Old 03-25-02 | 04:51 AM
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I hate it when this topic comes up because it always makes me want to go out a buy a 50 shot setup. I have a pretty fresh motor, but I think my fuel injection system is a little too shaky to risk it. Maybe I will get one in a few months, if anything to know that I got it when I need it. I gotta replace that "ghetto *** exhaust" first though.
Old 03-25-02 | 05:09 AM
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Originally posted by kim307
Another thing, why is it so hard to put a turbo on N/A? Damn...it's easier to put turbo on a honda than the N/A rx-7 which has a turbo twin brother. Something wrong with this picture...
Nothing wrong with this picture. It's no harder to put a turbo on a NA RX-7 than it is a Honda. It just makes no damn sense! Honda owners have no choice; they can't go out and buy a factory turbocharged Honda, so they have to build one and it ain't cheap to do it right. But you can go out and buy a factory turbocharged RX-7 (complete with a long list of factory upgrades), and it makes no economic sense not to if you really want a turbo.
Old 03-25-02 | 01:56 PM
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Originally posted by NZConvertible
Honda owners have no choice; they can't go out and buy a factory turbocharged Honda, so they have to build one and it ain't cheap to do it right. But you can go out and buy a factory turbocharged RX-7 (complete with a long list of factory upgrades), and it makes no economic sense not to if you really want a turbo.
And you figure that someone in last 13 or 14 years would develope a turbo kit for N/A. Come on now. From what I understand all it needs is an adapter that'll space out the turbo and some custom piping. Is that so hard to do???

Personally I'm planning on a p-port with 5th and 6th auxillary ports still attached. I was trying to figure out a way to open and close the p-ports only in certain rpms, but that's nearly impossible due to the location of the ports.

Jay Kim

P.S. Who's turbocharged their 6-port N/A(not n/a to t2 conversion) in this forum? Could someone actually measure the pipings and let others use it as a template?
Old 03-25-02 | 04:01 PM
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Where is a good place to price NOS systems??
Old 03-25-02 | 04:52 PM
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Originally posted by kim307
And you figure that someone in last 13 or 14 years would develope a turbo kit for N/A
Like I just said, there's already a turbo version available, so no one's going to waste time and money developing a kit that won't sell enough to be economic.
Old 03-25-02 | 05:39 PM
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How about nitrous on a turbo car? I've heard it was alright on an N/A, but havent really heard of anyone doing ti with their turbo II's.
Old 03-25-02 | 05:51 PM
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Originally posted by kim307


And you figure that someone in last 13 or 14 years would develope a turbo kit for N/A. Come on now. From what I understand all it needs is an adapter that'll space out the turbo and some custom piping. Is that so hard to do???

Personally I'm planning on a p-port with 5th and 6th auxillary ports still attached. I was trying to figure out a way to open and close the p-ports only in certain rpms, but that's nearly impossible due to the location of the ports.

Jay Kim

P.S. Who's turbocharged their 6-port N/A(not n/a to t2 conversion) in this forum? Could someone actually measure the pipings and let others use it as a template?
hahahahahahahahahha that isnt even close to the amount of sh*t you gotta do to put a turbo on there and actually get good power.

try this, low comp rotors, new flywheel and front counterwieght, ecu to control new engine dynamics, upgraded fuel system, entirely different pre-cat exhaust, oil feed and attachments for turbo.

this is just the stuff off the top of my head. sure you could get away with less, until you hit WOT and blow all 6 of your apex seals through the housings. it is complicated and even if you do it right, the engine life is far less than even a real TII

Justin
Old 03-25-02 | 06:38 PM
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Originally posted by kim307


P.S. Who's turbocharged their 6-port N/A(not n/a to t2 conversion) in this forum? Could someone actually measure the pipings and let others use it as a template?
Aaron Cake has a thread with pics about turbo"ing" his N/A.
Old 03-25-02 | 06:49 PM
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Originally posted by RX-7Impreza


hahahahahahahahahha that isnt even close to the amount of sh*t you gotta do to put a turbo on there and actually get good power.

try this, low comp rotors, new flywheel and front counterwieght, ecu to control new engine dynamics, upgraded fuel system, entirely different pre-cat exhaust, oil feed and attachments for turbo.

this is just the stuff off the top of my head. sure you could get away with less, until you hit WOT and blow all 6 of your apex seals through the housings. it is complicated and even if you do it right, the engine life is far less than even a real TII

Justin
I agree it makes very little sense to do it, you can't run as much boost b/c of the higher compression, but you're wrong on the front and rear counterweight and flywheel thing. Bolting on a turbo does not change the internal balance of the motor. This would be necessary only if a TII drivetrain was installed, but not if you "just bolted a turbo onto an NA car".
Sean
Old 03-25-02 | 06:51 PM
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Originally posted by chatch
How about nitrous on a turbo car? I've heard it was alright on an N/A, but havent really heard of anyone doing ti with their turbo II's.
Yep. NOS brand makes a kit for TII's.
A couple of the big boys use it above 3000 rpms while they wait for the turbo to build boost.
But you can go ahead and add it to a stock TII as well.
I think it'll be one of my next mods.
Sean Cathcart
Old 03-25-02 | 06:53 PM
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Originally posted by J-Rat
Where is a good place to price NOS systems??
www.summitracing.com
go with a NOS brand, they work great.
I can get you a part number if you want, but look to pay $500 for a kit.
(Or build a direct port nitrous system yourself- he he.)
Most of the other kits are dry, like ZEX, and NOS has great history, lots of experience, and good selection of parts and great customer service.
Sean
Old 03-25-02 | 06:58 PM
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Originally posted by kim307


And you figure that someone in last 13 or 14 years would develope a turbo kit for N/A. Come on now. From what I understand all it needs is an adapter that'll space out the turbo and some custom piping. Is that so hard to do???

Personally I'm planning on a p-port with 5th and 6th auxillary ports still attached. I was trying to figure out a way to open and close the p-ports only in certain rpms, but that's nearly impossible due to the location of the ports.

Jay Kim

P.S. Who's turbocharged their 6-port N/A(not n/a to t2 conversion) in this forum? Could someone actually measure the pipings and let others use it as a template?
For you PP engine, you could try that trick thats been mentioned a few times, but no one here has tried: Install a set of butterfly valves that open your PP's at a set rpm, say 5000.
As for the Turbo conversion, it just doesn't make sense. You can pick up a TII for $2500, and you would start off with a much stronger drivetrain (NA drivetrain will not hold up to Turbo power, you need everything from flywheel back, that includes tranny, starter, driveshaft, and rear end).
You'd need to figure out an intercooler, as the stock TMIC will not fit, so expect $1000 for a FMIC.
Stock fuel system for an NA will not handle boost, and you're motor will pop. Stock ECU will not handle boost.
TII is just better to start with.
It's like adding a motor to your bicycle... Why not just buy a Motorcycle?
Sean
Old 03-25-02 | 07:05 PM
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Originally posted by MasteRX
I hate it when this topic comes up because it always makes me want to go out a buy a 50 shot setup. I have a pretty fresh motor, but I think my fuel injection system is a little too shaky to risk it. Maybe I will get one in a few months, if anything to know that I got it when I need it. I gotta replace that "ghetto *** exhaust" first though.
Here's the deal. Your "shaky ***" fuel injection system has nothing to do with wet nitrous. Only your fuel pump.
To be safe, take precautions:
-never hit nitrous below 3000 rpm
-never hit it nitrous to fuel cut
-install a Fuel pressure gauge, and get off the button if your fuel pressure drops AT ALL
-follow proper jettings, via the calculator at: http://cosmik.org/calculators.htm
-never go over an 80 shot on a stock-ported motor
-install wiring so it can only be activated at WOT
-mount the bottle properly, wire a bottle heater properly, and use a purge valve.
-make sure you have an ample fuel pump, and a clean fuel filter.

Its just common sense, if you know what you're doing. Make sure the nitrous shot also has enough fuel, and you'll be fine.

Sean
Old 03-25-02 | 07:13 PM
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Originally posted by scathcart


For you PP engine, you could try that trick thats been mentioned a few times, but no one here has tried: Install a set of butterfly valves that open your PP's at a set rpm, say 5000.
As for the Turbo conversion, it just doesn't make sense. You can pick up a TII for $2500, and you would start off with a much stronger drivetrain (NA drivetrain will not hold up to Turbo power, you need everything from flywheel back, that includes tranny, starter, driveshaft, and rear end).
You'd need to figure out an intercooler, as the stock TMIC will not fit, so expect $1000 for a FMIC.
Stock fuel system for an NA will not handle boost, and you're motor will pop. Stock ECU will not handle boost.
TII is just better to start with.
It's like adding a motor to your bicycle... Why not just buy a Motorcycle?
Sean

I agree with some of this EXCEPT the part where you say you can pick up a T2 for $2500 bucks. In my area you are damn LUCKY if you can find an N/A for 2500 bucks. I have searched this entire state for a T2 under $4000 and come up with nothing, the only time that I have found a T2 for sale in this state was a few months ago and the guy was selling it for $8000(new engine, 90 model, still way too expensive) . For me it is more economical to get a cheap N/A and do the T2 Conversion. Around here my only other choice to get an already turbo rx7 is an FD. I have been searching for a T2 in the state of texas for over a year now and I am still empty handed.
Old 03-25-02 | 07:18 PM
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Maybe its just where you look? I can usually find NA"s up here for $2500-$3000 Canadian.
And I would never pay more than $4000 cdn for an 87 TII. Thats what they're worth around here.
Sean



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