I had one fail on me today, It cant handle high psi, It is an edlebrock...

What kind to you all recomend, I cannot afford for the gas cyl to fail.


What will cause the valves to float? Weak or worn springs?

 

I had one fail on me to. It was also the N2O. When the bottle was cold, iot would work, but when it heated up it would not work. Lost a race to it once. I think the one that failed was a I.C.E. brand. I don't think there is a better brand, it just happens.

Yes, or crazy RPM.

 

Thanks Doctor, thats what I figured, I purged the line from bottle to selinoid to decrease psi and then tried it at the dunes today, and the selinoid let the weak pressure through. Just like you said. I did get up to 1500 psi and that might have pushed her overboard. I thought it was the hobbs that failed, but I jumped it and new that was not the prob.
The selinoid was clicking and getting hot on the bottom of it.

On the valves- It may have been floating @ 10k, but I have had symptoms of floating @ 8k, so maybe I should freshen up the springs. They are a season old, kibblewhite. I first thought I was rich on top, or snorkle collapsing, But it was not floating @ 8k today on a steep hill..


Question- If I let the motor rev high for 8-10 seconds up a very steep hill, they seem to not float when under a good load, could be that after a while of revving, the springs heated up and could not catch back up and starting to float.?

Thanks again for the onfo. Im just a beginner.[img]i/expressions/face-icon-small-confused.gif[/img]

 

i don't think you're floating valves or they'd hit the piston and you'd be out a lot of money! but i would freshen up valve springs periodically and be sure i know what the RPM limit of my valve train is.

sounds like a fuel or ignition issue.

spark plug gap too big? i run 0.018".

 

Scooby, im running gao @-0.020".

I did run straight vp-110 octane today @2600 ft elevation, and this happened.. Now, I have not had this prob when running 114 octane designed for 4 strokes. Maybe its not burning right. The 110 did make me run alot hotter than the 114 does.
What do ya think?, Thanks in advance.

This has also happened @ 5500ft I try to get away w/ running a little bit lower octane, and when I added a decent amount of prop oxide the prob seemed to clear up and did not seem to stop pulling, After I added the igniter.


The 114 I use is a high dollar fuel that is specifically made for 4 strokes, It seemed to pull Very hard all the way through 8500k+... Also with the vp 110 I can see a bunch of un-burnt fuel blowing out of the pipe. with the 114 it has no visible fumes.

 

Not sure were you at on plugs, but a tad colder plug could help. What compression are you at?


jbt

 

Man, from the sound of it, it sounds like you are lean? But if it cleared up with more prop ox, then you would be going the wrong way if you listened to me????? Every time I'm lean it chops on the top? Thats strange. And 110 should cover you unless your running some kind of psycho squeeze with a high capture cam???? Sorry I can't help you more.

And now I have a question for you. I race in a class where they don't allow additives. I know I could get away with N2O if I kept the shot low, but I just don't want to look stupid if I ever got caught!!!! Also I would have to hide the bottle REAL good, and it's just not worth it to me. I have never ran prop ox. Do you like it? How much power, or better yet, torque do you pick up?? Cost of the stuff? Can you add more for more power? Does it change the smell or racing fuel? Sorry for the stupid questions, I'm trying to learn about this stuff and win some races. Thanks

 

I am running about a 20 shot (depends on whos chart you look at)----Prop oxide has helped me at higher elevation more than it does at sea level( I would say by a few hp). . And when I ran coxoc (Klotz) I had to jet way up. I do not run power adders w/ nos. The klotz power adders helped it rev way out on top.

Slowride, Im running 9's for plugs. And tooo high of comp, probably 14:-15:1.



BTW- I run my bike very rich, it runs better that way on the dyno. It is wierd, Maybe its the burn rate, but my bike loves the 114. Even slightly diluted w/ 100 octane unleaded it ran real good.. I have tested alot of the vp fuels.
Luckily today I did not need the nos with the competition I had, I would have been kinda pi$$ed.

If I get it figured out(which I will) Ill let you know what the prob is.. I need to hook into an air fuel sensor on the dyno.

 

GREAT site ANNIHILATER!!!! Where I race, they can't check the fuel. They can and do check engine parts but not fuel, so I might give some of this a try. Thanks for the help!!!

 

It magically vanished, I dont want your competiton to see [img]i/expressions/face-icon-small-smile.gif[/img]
Theres some other good info out there, but takes a zillion searches to find it.

Doctorturbo, what psi do you recomend for fuel pump? I am @ 5-6 psi.

Also, does a higher psi fuel pump push through more fuel calling for a leaner gas jet?