I am going to put my little maverick on the bottle. I have done alot of research on this so I am not going into it blind. But I still have questions that I think are best answered by people that have/are using the stuff. 1) Where do you run your timing? 2) Is your timing locked out? 3) How much fuel pressure are you running/with what shot? 4) What type spark plugs are you using? My set-up is going to be simple: single shot(no more than 250) I will have it "button activated". This is going to be a use if needed or whenever I get the urge type deal. I am going to run in a heads-up class next year and I will only push the button when I need it to get around someone. Consistancy is not what I am needing. Thats why I will not have in activated at full throttle or by RPM range. I am sure there will be more questions later. Thanks in advance, John.
I use most of the advise just mentioned as far as plugs and timing go. Even if you use a button to turn it on and off you should still run that through a full throttle to make sure the nitrous never comes on umless you are at full throttle.I have been running a 100 shot with a holley red pump with the lines going right to the nitrous plate and carb. this worked but wasn't consistent. Now I am upgrading to a holley black pump and using an aeromotive regulator to send 9 psi to carb and nitrous because I am going with a 150 shot soon. 9 psi is enough to run a 150 shot. I am also installing a fuel pressure gauge to make sure I never hit the nitrous when fuel pressure is to low and to make sure it dosn't drop while on the nos.
I will not have in activated at full throttle or by RPM range. It's recomended that you only hit the button when you're at wide open throttle and turning at least 2500 rpm, unless you're running a progressive controller. I've been running nitrous in my car for about 12 or 13 years. NOS Super Power Shot and a Jacobs Nitrous Mastermind. The Jacobs unit retards timing when N2O flows, controls start and peak rpm flow progressively, has a rev limiter, and monitors fuel pressure. I have a switch on the shifter because I generally only want it to come on in 3rd and 4th gear. The engine revs so quick it's almost useless in 1st and 2nd gears. I'm running a 125 hp shot and I have it set to retard the timing about 6 degrees. I just installed an Edelbrock Performer fuel pump, high volume, 6 psi (wish I had done that before we raced at Roundup ).
Well, since you are gonna be racing it's not quite as simple as setting up a street car for nitrous. You've already got some pretty high compression so you will want to use some really good gas. I suggest VP C-16 and nothing else. You will want to run a seperate fuel system completely independent from the motor, don't skimp on the fuel system!!!!! Nitrous requires the motor to be retarted so you will either have to manually turn your timing back (which will cause the motor not to run it's best off the spray) or get a retard box that can pull timing out when you are on the spray and leave it advanced when the nitrous is off. Since you are probably running a mechanical secondary carb you should just lock out the distributor, which may require a start retard to help with starting. As far as the push button, i've always been told that it's probably not a good idea, too inconsistent and as hard as your car leaves you might have trouble keeping your finger on the button!! So far i've been running my timing at 36 and on the 225 shot and i'm pulling out 8 degrees but I only have 10.5:1 so yours will be different. Fuel pressure is one of the ways to "tune" your nitrous system, each different manufacturer will suggest different pressure settings for each of there horsepower settings and you can fine tune from there. Autolite Racing plugs are by far the best to use with nitrous, they have a shortened ground strap so it doesn't get so hot. I have covered very little on the subject but i'm sure this thread will bring out alot of good points.
Thanks guys. I already have my timing locked out. 25* start retard already installed. High rpm retard already installed. All MSD stuff. I run the 112 racing fuel now, uping it 116 is not a problem. As far as the button activation goes. My car leaves hard enough now, thats why I do not want it activated by throttle or RPM's. The class I will be running requires 26.5x8 inch tires. I figure I will have a hard enough time getting it to hook on motor. With the set-up I have now, my car would have qualified #2 last month. I figure once I add the weight and the mufflers. I should still probably be in the middle of the pack, on motor. The NOS is just for a little extra. Thats where the button comes in. If I need it at the top end(3rd gear) I will use it. If I do not need it, I would rather not. I will do some research on the button. I seen that is how Jim Allen has his set-up and I did not understand why he would not have it on the throttle. But I think it would give you more control over your car and traction if you could hit it once the car was well on its way down the track. Again thanks for all the comments, and I welcome more. Its going to be a new game for me. Never heads-up raced and never messed with NOS. Please keep them coming.
Been runnning NOS (yes, the brand) for many years. I run the basic timing that most above mentioned. I run the fuel at 8psi to the plate (125shot, NOS Powershot) and 9psi to the carb(predator). I have always used the button mounted in my shift handle. I too smoke first gear and end up on the gas at the second gear shift. Putting on 275-60-15 drag radials this weekend, should be able to hook better. Have fun, Scott (I like the mastermind, but am too cheap to buy it!)
my set up is on the throttle, i like that just cause of there being one less thing my brain has gotta be on to get this heap down the track,, we run 7 psi of flowing pressure on the NOS side, the timing we pull out 7 degrees on the spray which is on a 2step retard where it pulls 3 degrees with the flip of the switch and the rest at WOT, and as far as plugs go we run NGK's, what ever you do dont use Champion plugs! they just dont hold up for $h!t!! but everybody else have covered it pretty good, and yes once you try it you'll never go back!! lol
Just thought of something else. What about purging the system after a run on nitrous. I read where they say to turn the car off and then shut the bottle off and then use the purge to get the nitrous out of the lines to relieve the line pressure that is on your nitrous silynoid? Any comments or suggestions?
Yeah, that's just to relieve your pressure on the selonoind so it doesn 't get damaged.........long periods of time with that much pressure on the nos selonoid can cause damage.
John, a couple of things to keep in mind......it is important that you spend some time tuning your car on the nitrous before you go to a race and let it rip. One thing i've noticed on these small block fords is that the #4 and #8 cylinders like to lean out before the others......there are several reasons for this but mainly because of distribution problems in most single plane manifolds. Spark plug reading will become important. Also, like jim said, you need to set the fuel pressure with it flowing through the fuel jet that you will be using.....i'll get you a picture of mine. If you are interested, i've got a cheater kit (minus the bottle) that I could let you borrow. In my experience, the best kits on the market right now are the Wilson Manifold Kits (Nitrous Pro Flow) but they are very expensive!! Another good idea is to run a spacer plate that has the blow out panels, so if you get a nitrous backfire it will just blow the plates out and not hurt the carb or intake. There are lots of good nitrous sites out there that have lots of good info.... fastlanenitrous.com here's a message board that has given me alot of good info... http://www.gofastzone.com/forum/forum.asp?FORUM_ID=14 I'll try to find some more......
No problem John, let me know if you want to "test the water" with that cheater kit i've got. It's just taking up space in the tool box. I'm attaching a picture of the flow gauge that I use to flow the fuel side of my nitrous system, I got it from grainger and it measures in 1/8th lb. increments.
Thanks Stephen, I will let you know. The car is in pieces right now and will probably stay that way until sometime next year. Its ready for paint, but for some reason Unlimited is taking their sweet time shipping my hood! When I talked to them last month they said it would take 2-3 weeks, now I talked to them yesterday and they said 8-10!!!!! I know they are changing shops, but what the hell?? I guess I should have went with USBody. Live and learn.
something else.... Where can I get that spacer with the blow-out panels? I looked through my Summit and JEG's catalog today and I did not find them in there.
