minytrker

iTrader: (13)

LOL, here 99% of the tracks don't have tech, they are far from IHRA or NHRA tracks. These are mostly for grudge racing. You have to wear a helmet and have your seat belt on. Some make you wear a jacket if your in the 6's in 1/8 mile. Some you can run without a helmet if you run slower than 7.50's.

GueSS Who

There are so many different vairables. I know lots of outlaw cars that don't run more then 900psi. Keeps the tune right on, for the entire track. I also now some big nitrous motorcycle guys that won't run over 800 psi.

I personally don't have that kind of power but I run my bottles at 800psi and sometimes 850. During the summer I have to put them in Ice chest to keep them where i want them. But I don't ever have any bottle drop either. As far as 2 bottles it mainly depends on how much they are spraying. 1 single -6 line is only good to 600 if there is no 90s in the system, so if you are spraying more then that, which most outlaw cars are, then you would need 2 -6 lines with a pressure equilizer in between and then you can spray alot more without having pressure drop.

68maro

then you've never been to a big heads up race, 75% of outlaw guys use a torch. and what kind of class doesn't allow a bottle heater?

GrahamHill

iTrader: (6)

Did anyone investigate a bottle explotion when a hand held torch was used? Sounds more like a faulty pop-off valve was the fault rather than the cheap lil torches actually getting through a bottle. Those things take forever to even get a red spot in sheet metal, much less hurt a nitrous bottle. It just seems like the nitrous would oxidize the torch flame so much it would just put it out. Plus nitrous isn't flammable.

DMH Fabrication

iTrader: (126)

It wouldn't necessarily have anything to do with putting a torch flame out. When you heat any metal, you change the grain boundarys and strength of the material. At the same time you are doing this you are creating a higher pressure in the bottle and it can cause it to explode from the walls not being strong enough for the internal stress. Having a metal tank explode is obviously not good.

With that said, I see almost everyone at our local tracks heating the bottles with a torch. I would never do it though.

Ben R

I raced in IHRA Pro-Modified for a season so I'm probably pretty qualified to answer the questions.

Most N20 Outlaw 10.5 cars are using 4 systems instead of 3 like the Pro-Modifieds because they can't bring the power in as quickly as the Pro-Modifieds do. In Pro-Modified we used a Hot Box to bring the 2 10 lb. bottles up to 1,300 PSI before we put them in the car. This is done to keep the pressure up nice and high because a lot of times we end up sitting in the staging lanes for a while and we don't want to have to re-heat them. A lot of teams also use bottle pressure to operate their air-shifters on their Lenco's.

As far as how much N20 is being sprayed, every team does things a little differently, but our tune-ups had 4 jet spreads and each system was run on a bit different fuel pressure. We also had a 4th system we used as a high-speed lean-out, but that was guaranteed engine meltdown, so it didn't get turned on very often. One very popular baseline tune-up that comes from Fulton is 36-32, 28-24, 22-18, 18-12 for the little tire cars.

As far as the torches go, everybody knows you're not supposed to use them, but guess what, everybody uses them. As long as you keep the flame from being in one spot all the time, the bottle won't blow up. And besides, if your bottle really is full (Most racers only put about 9.5 lbs in a 10 lb. bottle) it will re-pressurize very quickly. And most N20 tune-ups are designed to be run between 950 and 1000 PSI at launch. And no, more bottle pressure doesn't equal a harder hit.

Ben R

Teams run two bottles for a few reasons. First is that there is a limit to how much N20 can flow out of the bottle all at once, and with the systems as big as they are you get close to that limit.

The other popular reason is to help keep bottle pressure more stable throughout the run.

A lot of teams also weigh their bottles before and after each run to help them keep track of the tune-up and to identify problems when they start melting pistons.

car_fixer

when i see the torches come out i move as far away as i can get. I have a heating blanket on the bottle, but when its cold and first getting to the track, we put the bottles under the hood of the truck and lower the hood, works pretty good, we have gauges and caps on the bottles to watch the pressure.
A guy i work with won the first fastest street car thing,(crew guy, and helped build the car) and they had 1 fogger , 1 plate and 2 spray bars installed in the intake, i dont know how many they used at once, or what hp, but im guessing more than 200 lol

Ben R

The only engines I know of using 5 stages are the 5.300" BS 870+ CID engines that Fulton and RM are building. And there are only a handfull of them being used right now.

Ben R

There is no pressure equilizer on any of the N20 plumbing I have seen in Pro-Modified. They want to keep the bottles seperate for tuning purposes.

JUICED96Z

iTrader: (2)

Some of the tech guys up here are not informed that well. I know last year they kept saying bottle heaters were not allowed for Div 3 I think it was. It was resolved later.

Im not really into the classes or anything like that. I just mess with heads up run what ya brung stuff.

I have never seen any pro-mod guys use a heater but that does not mean they don't .

Ben R

Not many Pro-Modified cars have bottle heaters wired into them, but most will use towels to help control the pressure.

JUICED96Z

iTrader: (2)

Ahhhh.

GueSS Who

Well he was asking about outlaw 10.5 cars and I personally know plenty of them that use a crossover hose to equilize the pressure. If you use different fuel pressure for each kit like you said above why would you want to use different bottle pressures also. Seems like more of a cluster **** to me and even more tuning. The more stuff you can keep common the better off you are with your tune. I could definitely understand the different fuel pressures though. more pressure on the furthest timer. What do I know though.

Ben R

LOL, the bottle pressures are going to be very close. If you've filled the bottles properly and are using bottles with a good valve in them (Speedtech or the upgraded NOS valve) you're not going to see a big drop in bottle pressure from start to finish. We used to leave the line at 1,000 PSI and when we crossed the finish line one bottle would have about 880 PSI in it and the other about 920 PSI in it. Pressure equalizers aren't used and aren't needed in either Pro-Modified or Outlaw 10.5.

I guess not much, cause you've got that backwards.