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Old 06-12-2011, 02:55 PM
JimLev JimLev is offline
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Location: Sundance Mesa, NM
Join Date: Dec 2003
Posts: 4,319
Mein Auto: 540/6, '16 Highlander XLE
On standby??? I don't think so. I've had it on this engine for the last 8 years.
200HP on a Civic, bet it would have had a better chance of surviving if you had a progressive controller.

Bluebee, you wanted more info.

I've been using Nitrous since 1990 and haven't had any problems.
The key is not to abuse it with too much boost for the size engine you have.
Summit Racing sells them. I got an NOS kit for my 300ZX back in 1990 and when I sold the Z I kept the NOS for my 540.
A turbo or supercharger will cost you big bucks to buy and install, and will decrease your mileage because it is always available and you will use it more than you think.
When you sell the car your supercharged/turbo is gone, your need to start all over. NOS can be moved from car to car.
I went the N2O route because it was less than 1/10 the price of the other methods and much easier to install.
I don't use it that much in the 540 because it has adequate HP without it, but the more HP the better has always been my motto!
The only down side is you have to get the bottle refilled when it runs out. In MA it costs ~$50 to refill a 10 lb tank. There are 15 and 20lb tanks that come with some kits now. I bought a 20Lb tank.
There are wet and dry kits. Wet injects gas and nitrous into the intake. A dry kit uses just nitrous and fools the injectors into dumping more gas into the cylinders to keep the air/fuel ratio within reason.
I prefer the wet kit, as you don't need to tap into the computer or fool the fuel pressure regulator to get the injectors to spray more fuel. With the wet system itís easy to change either jet to get the ratio correct.
The extra power comes from the extra gas that get delivered into the engine, the nitrous is just there to supply O2 to burn the extra fuel and to cool down the intake charge.
You only use nitrous when the gas pedal is floored. For a 528/530, a 40HP boost is real safe. My 300ZX had a 3-liter V-6 and I was using a 60HP boost. (After 180K miles on this engine I took it apart to add ISKY cams, head and intake porting and polishing, etc. I miked all the bearings, rings, journals, etc. and all were still in spec, granted on the low side of in spec, but still OK. The engine still didnít burn oil).
The fogger nozzle has small jets that you can change to vary the HP level, a 2-minute job.
If youíre looking for bigger boosts a 2-stage method is advisable, as you will limit the sudden jolt of power to a smoother transition, which is much better for the drivetrain. I have my initial boost set at 50HP which then ramps up to 125HP in 1.5 second. Then if I have the second stage enabled another 50HP comes on, for a total of 175HP.
Another thing to know is that the bottle needs to be warm to keep the pressure up. In the winter it is just too cold for even a full bottle to deliver adequate pressure, so you may need to get a 12V bottle heater (~$120) if you want to use in the winter. I don't drive my car in the winter so that isn't an issue, but I added a heater for those cold spring and fall days. If the pressure is down you won't get all the HP you would with a warm bottle, not enough O2 to burn the extra fuel. ZEX has a kit that touts a nozzle design that says it delivers the correct fuel for any bottle pressure, and they say that they control the fuel delivery by measuring the N2O bottle pressure. All of the different manufactures use a similar nozzle design. ZEX does have a nice kit, they are just marketing it to a different crowd than NOS. ZEX is big with the import crowd and has packaged their product better than NOS. ZEX has the solenoids in a box, you donít see most of the plumbing.
One last comment, nitrous doesnít like advanced timing, as most chips and software downloads do as part of the ďprogramĒ to get more HP. As a general rule the timing should be retarded 1į for every 75HP boost. I was running the stock DME software and have no problems with a 100HP boost. When I went to the 175HP level I added water/methanol injection and used NGK iridium plugs (1 range colder) to prevent pre-detonation.
I donít know what the degrees of advance are on the various stages of software upgrades, but BMW engines do have knock sensors on them to retard the timing if pinging is detected. I always 93 octane fuel and have no issues. 92 Octane is recommended. Iím now up to 175 HP boost using an NOS Progressive controller. I also have Dinan engine software, no pinging has been detected.
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