Was at the dyno today and made 3 runs on the bottle. I'm pretty sure my bottle was starting to run low although I still had over 900psi readings. It was pretty light when I pulled it out though. Anyway, each time i'd nail it, for the first 500 to 1000 rpm or so into, my A/F would spike up to about 10 to 17:1 then quickly come back down to around 13 and keep going down through the run. My last run did the same thing, but looking at my scan, it pulled no timing when it spiked to 17, so it must not have been detonating even though it was lean. It didn't do this on my N/A runs either. My question is this: Is this a result of my bottle starting to go empty or you think it's something else? It didnt' do this last week on the dyno and everything was the same then except I had a fuller bottle. I'm running a dry kit, so it does use the nitrous to kick up fuel pressure. Still a nubie on the bottle, so still learning. Any input would be appreciated. Thanks in advance.

Ken R. 95Z

 

IT could be a few things. But if it was working fine last week and just started doing this I would check the line from the N2O regulator to the fuel pressure regulator. Also check the fuel filter. Where do you have the nozzle mounted? I've seen guys mount it real close or even behind the TB which can lead to a lean spike at first.

 

Could be that your regulator can't react fast enough to raise the fuel pressure or worst case is the increased pressure is causing your fuel pressure to dip initially and your pump has to catch up. Get an intank 255 fuel pump and see if that helps.

Matt

 

Ken,
Make sure your bottle is full and mounted at a 15 degree angle. Also make sure the bottle pressure is 950 min. I have a lot of info on the 5176 system. Send me a e-mail. compta57@cinci.rr.com
Mike

 

Thanks for the input guys. I'm gonna see how it runs when I fill my bottle this week. Mike, you'll have e-mail shortly.. Thanks.

Ken R. 95Z