I am totally ignorant on NOS (lol some would say on everything). Here is my question. Lets say you gain an average of 4 hp by jumping up to 13:1 from 9:1. Lets say we throw an 8:1 Turbo piston in the bike and run a 50 shot. We give up some of our all motor performance, not just hp and trq but also rev quickness that comes with high compression. We then trade it and a 25 shot for a 50 shot. We net gained about 20 hp if she holds together.

I want to know why that wouldn't work on a strictly power adder race bike?

Keith, I missed your question...........I don't really know what the max is on our motors at our compression. I just know that most are running a 15 or 20 shot and only the ambitious ones are venturing to 25 and 30 shots.

 

Very good questions indeed. Heres my OPINION.

First, most everyone here runs there bike mostly off the button. So we want a good amount of compression for most of our riding. We then add a nice little hit for the times we race. Its the safe way to do it.

You can run high comp and high shots, to a point.
To do this you will have to solve the issues that will arise. Detonation will be the major problem, and heat the other.
To solve the deto, you can do many things, and you probably know these but I will list them anyhow.
First, Octane. It will slow the burn rate down.
Plugs. They help dissapate the heat in the plug. The down side to these, is some times it will give you a false sence of confidance. But they will hold the tips longer, and remove more heat from the chamber.
Timing, and when you get into the larger hits, this will come into play even more. Advanced timing likes to ignite the charge before its ready. Now add alot more heat, and you get deto.

Ok, so heres my jist of it all.
If you want a full race motor on nitrous, you first need to decide how much nitrous you want to run. You have to remove the heat from the motor to get into high levels. Heres where drag pipes will do the best. Nobody that I know of has tested the levels this motor is capable of taking. So we dont know how much nitrous, is to much with said level of compression, too many variables. We know many run 14-1 with 20 shots. High level of octane, advanced timing, and cold plugs. Now I believe someone is about to try the higher doses on a 14-1. We'll see how it goes.

If you really want to run high amounts, on long sustained pulls, I would run lower comp. It will not be such a bang on the motor. The short runs, you dont build near the heat, so you will get away with alot more.

Dont over look cooling in this. If you can help keep the cylinder cool, you will be alot better off.

Its all heat, and you just need to remove it.

 

woods cdi and nitrous 2 years no kaboom, one tach [img]i/expressions/face-icon-small-smile.gif[/img] lucky? i guess but what does nitrous do? it makes your engine excellerate really fast, when it hits you just shift faster, if you don't kaboom. the limiter is good insurance, but would the woods cdi be my first choice no. as far as nuts question on lower compression, that is the better way to run nitrous, the problem being once you feel the rush you never want to go back to normal, the most disapointing thing about nitrous is the bottle going dry. and with the lower compression the difference is large. there are support lines at the nitrous places they will talk you thru your concerns. i highly recommend you check into it, before you install and run a system.

 

Amen on the going dry thing. They never seem to last long enough. I need to join the NA....(Nitrousaholics Anonymous)hehe.

Bill, what comp are you running?

 

seems it was in the 10 range, maybe less. how many times have you over reved on the juice? maybe my luck was from a lot of space between the valves and piston. or maybe gary just got it right on mine, everyone thought it was funny his engines were popping on nitrous, but the r-n-d worked for me, and i run the dangerous wet system[img]i/expressions/face-icon-small-smile.gif[/img]

 

Sandman is correct. There are very few people that have a "strictly power adder race bike". Thats why I have recommended what I have. Part of the fun if N20 is using it when you need it. Talk to your builder or N20 guy and they will ask you questions to determine what you are using it for, and how you are using it. Then your components will follow.

 

involve the nitrous guys is great advice, gary put the system together and i must have made 25 calls on mine 2 nx and followed all the instructions very precise. I've had great luck with my system, inpart gary did all the research on mine so that made it easy for me. the biggest problem i've seen is people jetting for more power than recommended, and cooking engines from being to lean. other than that nitrous has been my best mod and i've done plenty to compare too.

 

Bill, I cant count the times I have missed a gear, or thought I had the right gear, and sent her singing. But my rev limit is 8900.
I have got mine to lean also. Left me with no plugs, and now I am replacing my piston. All systems cause problems if your not careful.

 

well my system seems to go rich over lean since it is the bottle pressure that fades. i start in second which reduces the chance of a missed gear.

 

Ah, you brought up a good point. Length. I know you have ran the bigger hills, but they take more shifting. If I start in second, that still gives me two shifts. I was starting in third on the button, but my clutches didnt like that. I was doing it to miss one shift. Now if you had a cutout on your clutch, that shuts down your sytem momentarily while you shift, you could solve that issue. I shift at full throttle, spraying. Thats probably why I am so for a rev limiter. Your low compression makes me think thats why you havent had many issues with the advance. I put on a Ron woods box to test, but never got it under the button. My bike would not run worth a crap with my carb settings, it would just spit and sputter. So I took it back off. I have seen your bike run, and run it does, so I wont questions ya.