get a dyno tune, and get some tires.

 

I understand what all of you are saying about the tires and traction, etc.. however here is the weird thing about the nitrous - The hoses and fittings don't get very frosty, even when opening the bottle itself, the charge coming out is not ice cold, its cool - but definitely not freeze your fingers cold. I have had the bottle filled at 2 different places and it seems like it is half air and half nitrous or something. I have noticed this when I emptied it to install the blowoff valve, and just testing to see WTF was going on. No white cloud at all. The pressure is usually too high - like 1200psi - because it gets so hot in the trunk. I generally have to ice the botle to get it down to 900 psi, which is where it was for these runs. I know it is spraying because I can hear it, and I do feel a bump when it does hit, just not like I would expect it to. And tires won't keep it from bogging down at half track.

I know the smart thing to do at this point is to get a dyno tune (and ultimately tires/suspension) I just hoped there was a common issue I am overlooking or somebody had seen this before.. (for example - bad bottle filling technique - is it possible I am getting bottles with air/nitrous mixture instead of all nitrous --- or could periods of overheating/overpressure cause the nitrous to be bad)

 

There is a guy in town with the same issue. best run is a low 14 off the nitrous and then on the bottle wasnt as good.

problem was before he bought the car the guy had a blower on it, and we dont think the previous owner removed that tune. After he made the pass his car was loading up. and when he left the track he had a time getting it started because it was flooded. He has a NX wet kit, no clue on what size shot, but im going to assume 75 or 100.

Probly be next month when he makes another pass but will be getting a dyno tune before then



Also here's another thought, elimate the possiblity of weather change. I can not imagine it being a big issuee unless you was using a different track along with a worse weather.
What was you weather like(temp, humitity, barometric pressure), and what altitude is the track at, for both the na run and nitrous. . http://www.wunderground.com, enter the zip, scroll down and look for the History & Almanac, and enter the date of both track days, should give you what your looking for,look at the Hourly Observations. Then theres some calculators for determining et and trap at sea level. Calc I use thats at Modular DepotCalc I use thats at Modular Depot

 

Weather was essentially the same. Probably hotter and dryer on the best eta - like high 90's. Bad runs were low 90's and more humid. I don't think weather was the issue. I am going to try a different track this weekend and let more air out of the tires. I should still get a dyno tune first...

 

First of all, GET A TUNE!!!! IF you are mix matching gas and tunes, you are asking for trouble and/or not getting full performance out of you car. I got a 93 octane tune, you should tune for the highest gas that you can get in your area.
Besides that, I would say that you are losing traction. When are you spraying??? Is it off of the line or in what gear???

 

Im not mixing or matching randomly. I am using the 87 tune because there is no timing advance like there is with the 91 tune. For a 75 shot you don't have to retard timing according to Zex. I am using the 91 gas because It is minimum required octane for nitrous. So that is not the problem.

I think it may have been a lose fitting now that I have dug further. The hose to the nozzle on the intake was loose. I also found heavy deposits of black/brown on my plugs. I am guessing that i have been shooting mostly just fuel in and running rich - causing the bogging out and the deposits on the plugs. Unfortunately when i went to fill my bottle on Friday, checker had no nitrous left. I will try on Tuesday when they get refilled and we will see if it is hitting better. Then to the track this weekend and trying to get a good launch.

 

this is why i still think DRY is a lot better....less to go wrong, unless your running 150-200 shot....but then i would call that a track only car..