if you use the new NX dry MAF kit and a Timing twister you would be set. You could spray your 150-175 shot and adjust AF with the control ****...and then retard a little timing with the timing twister. Just be sure to check your AF on the dyno or with a wideband o2. You would not need a laptop for that.

 

does it change because of the torquer v2 cam that i got????
Im running cam only right now

 

How do you have this discussion without stating the obvious.

Less RPM ='s Greater cylinder pressure.

Nitrous has an effect of 150 hp at 5200 rpm with a 150 shot... yet at 3k rpm the cylinder pressure is like a 300 shot. This is the benefit of a dual stage kit or a progressive. Something that my Engine builder explained to me after I told him I wanted to be able to spray a 300 shot.

Funny thing about my situation is I was spraying with 300 "pills" but due to stupidity I only gained about 200rwhp...... rats nest of an install and almost little to no proper tuning. Live and ya learn.

 

Very true, and thus my choice to go triple stage. Yes, big torque down low can be a hand full for the motor concerning cylinder pressures. Higher rpms will have the tq staying around per stroke for shorter periods of time and thus less chance of damage.
Robert

 

true for a dual stage but not a progressive.
A progressive just pulses the 300 shot, your not getting 150 shot than 150 shot. The motor is seeing a 300 shot your just turning it on and off FAST.

 

ATV thats not exactly true....or maybe I mistook what you are saying. A progressive can be much easier on cylinder pressure as well depending on how its setup.

If you have a progressive with a 300 shot and its set to ramp by time...or rpm...you would really have to look at a dyno graph to get an idea of what cylinder pressure the motor sees at certain intervals. You have to look at the Tq line. The higher the Tq line the greater the cylinder pressure. Tq is a direct measure of avg cylinder pressure. So lower TQ = lower cylinder pressure. And a pogressive can really do a good job at controlling tq.

As a matter of fact...and I have been preaching this for a long time....tuning is only half the equation for me. The other half is actually planning your TQ output at various places and rpms. When I put together a bottom end...I then plan for the TQ I want that bottom end to see. Stock bottom end I dont like to see much more than 600 ft/lbs.

Budget Built bottom maybe 850. The target Tq in that case also correlates to a rough guestimate of cylinder presssure the engine will see. That helps you choose your octane and timing requirements as well. Because applying octane and timing requirements is much easier when Tq/cylinder pressure is more managable and does not have wild swings one way or another. A nitrous car that has 800 ft/lbs at 3000 rpm and then drops off to 500 ft/lbs by 6000 rpm with a single stage hit is a nightmare to tune well compared to a setup that maintains 650 ft/lbs from 3000-7000.

When I setup a nitrous kit...its with the motor in mind and a target Tq. I try to stay withing 75 ft/lbs thruogh out the usable rpm. That makes the tune you choose much more reliable and easy IMO.

 

I understand that the dyno will show that its smooth but if you have a Direct port with a 32 N20 jet in each hole every time the progressor turns the noid on the cyl. is seeing 300hp worth of N20.
I know it will be different if you just have a single nossle in front because the single nossle is feeding 8 cyls. and the intake is helping to distribute the fuel and N20.
I still like 2 stages over hammering the noids but its all personal prefernce.

 

I have known alot of people that this has happened to. Lifts the rings just as fast or faster then lean



Don't see that low RPM. My converter goes to 5K on the brake. I missed all that low RPM grunt that hurts motors. There are so many classes out there where you can only use 1 kit. These have to use controllers for the big shot. 2 stages is more for traction then engine wear IMO. Properly tuned nitrous doesn't matter if it is 1,2, or 3 stages. You can't leave off 500. The most we can leave off of is 300 on slicks. As far as the controller thing goes. I have had damn near every controling system out there. I like the NOS digital controller. Here is where it is tricky. On the dyno if you start with 50% and ramp it to 100% in .5 seconds and then you lay it over the graph where the controller was set for 100% all the time, you get very little difference. Only the torque number really changes. The RWHP graph is very similar because the solinoid is opening to what ever the pill size is. Which means it is still making that pill size hp, even if it is turned right off. Like what was said above though the torque number is changed when the controller is on. Believe me we have tested so many different kits in so many different ways. We have a dynojet to use at RPM. We use the widebands in the car along with EGTs and we check our plugs alot. If people only knew how much different each cylinder is with temperature on a stock intake (WET NOZZLE) they wouldn't use them anymore. There is not any nitrous system out there on the shelf to buy that is efficent. THE BUYERS HAVE TO MAKE THEM EFFICIENT. That is why there are places out there that will flow your intake for you. Making sure each cylinder has the same amount of air,fuel, and nitrous. Steve Johnson, or Wilson Manifold, or Chuck Roberts. All these places specialize in just this. I understand, not everyone has a **** pile of money. I don't either. That is why I bought an EGT system so that I could to it myself with independent cylinder adjustability from my BS3.

 

I see what you are saying...but that scenario is still very unlikely. To get an idea of cylinder pressure you really have to take each combustion cycle and look at it seperately. Dont forget the progresive doesnt change rate of cycles...only pulse width. So it actually doesnt get the full 300 on every cycle..it gets a portion of that since the noids stay open for less time...at a specific freguency.

If what you say is true then you would have to have erratic cylinder filling from one cycle to the next. Meaning ...as the noids pulse....each pulse is probably less frequent than each cylinder combustion event.

I dont have time right now but if you wanted to figure this out...figure out the cycles per second you have your noids set up to cycle...then figure out how many combustion cycles there are at max rpm on your setup. If the noid cycles exceeds the cyclinder cycles by a good margin...each cylinder fill should be somewhat even. If its less than or equal to....its likley to be very erratic.

Meaning that on one cylinder you might get 40hp on one cycle and 60 on the next....and then of course each cylinder would vary as well. If my progressive was that bad I would not run one.

Ill be honest here though...as much as I love the concept of progressive setups...I have seen erratic behavior at times with DP wet progressives with a single pulse. Your suggestion may be why ( I need to do the math later to see if its close enough to be an issue)

If I ever run another progressive DP I will use something like the FJO mini dual stage and use both stages in progressive mode with two sets of independant noids feeding the same lines/nozzles and basically double the frequency they are pulsed.

But for now I have had soo much luck with stages...Im sticking to that.

 

Thats what happened to mine at the end of last year.



I went ahead and bought the FAST XFI and will be getting help from Jeff Prock. Hopefully I can go a little faster and not hurt to much stuff.

 

I have never done any testing to know for sure.
Just like you we have had to much success with stages to change anything.

I dont worry to much about the big tq number because just like Guess Who my car flashes to 5,000 or more on the spray.

 

My car flashes to 6000 on the bottle hit. I run it to 8500 and the shift extention brings it back to 7500. I have a good *** converter for this to happen. It is still not there yet though. I plan on spraying another 200 which should make the converter optimal. I would like it to flash to 6500 and shift extend to 7800 and then pull back to 8800.

 

what about combustion chamber area-does this help to reduce cyclinder pressure?
Nick--

 

Ok, when guys are saying, well you still get the 300 shot it's just on and off. It seems to me that in words this is true, however, in reality the on/off, on/off limits volume. So, I contend, that a 300 shot wouldn't really be a 300 shot, at least in average through out the run. I know GuessWho stated that the HP does stay the same and only tq changes. I have had this discussion before, and I guess I just don't really comprehend that a progressed 300 shot remains a 300 shot thought the run, at least in the HP sense? Can someone explain this so as a dummy can get it, lol?
Robert

 

If you are really limiting the nitrous with the controler alot then I would say it would make some more of a difference. Anyone that uses a controller only limits the hit and usually not that much. That is why I said 50% to 100%.....If you go 20% to 100% in 2 full second then it would probably make more difference. This would mean that the solenoids were off more then on. LOL

The jets in the kit is what makes the power. Even if it is a split second that was a burst of a 300 shot.

 

BINGO and the reason i wount progress anything always stages.

 

Ok, I think I got it, and understand what you mean. Lets say a guy runs a 300 hit starting at 30% over a period of say 8 seconds till full on 100%. That would mean in reality that in the beginning of the run he would be only actually be putting about a 100hp hit down and progressively upping it till the full 300 came on? even though it's a pulsed on/off 300 hit, because of volume and the RPMs it just works out to a smaller hit. I could see running a DP and having more of a variance per cylinder, than if the plenum volume of a front nozzle location was used.

Then we have a guy with a 300 shot that starts at 50% and has it all in in the first 60feet, too quickly to really limit the hp, but can help control the TQ.

God, I am glad I am a full on staged freak. Seems the vast majority of the fast guys run stages, and there is reasons, as has been pointed. Sorry about the babbling, but have taken two of my back pain pills, lol.

Robert