NITROUS OXIDE ( nos / n2o ) advice forum

So I entered my car at the streetlegal drags in Drachten Holland Friday the 24 th.
Had high hopes on improving my times. Last year my best run was a paltry 14.45 E.T. although I was half asleep back then from the painkillers I had taken because of my backinjury and my nitrous sytem wasn`t dialed in yet.

Unfortunately the weather was far from perfect. Now and then some rainclouds came over, halting the event momentarily and limiting the amount of runs I could make.
On top of that there had been a professonal dragrace from the Dutch Explosion drag organisation one weekend prior to our event, so the track was covered with a layer of oil, sand and dirt mixed with water to annihilate traction severly.

I made about 8 runs, some in the wet, others on a partly moist track.

My first run:
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14.10 seconds E.T at 167 km/h
semi slick 2.2 bar tyre pressure
launch control 3900 rpm
30% ramp up 6.5 second on minimax
200N/70F at 950 psi
window switch at 3000-7900 rpm

Lousy reaction time (0.881 sec) and I shifted a bit too early causing wheelspin in 2nd gear which cost me time.

This was my second run and my best:
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13.90 seconds E.t. at 164 km/h tyres set at 2.0 bar
launch control set at 3900 rpm
30% ramp up at 8.5 seconds on minimax
200N/70F jetting at 950 psi
window switch set at 3000-7900 rpm

Massive wheelspin in 1st and 2nd gear, only in 3rd gear can I put the power down, but then the car goes like the clappers. I even have to shift into 5th gear right before the finish or the car will bounce upon the rev limiter at 8400 rpm. I might raise the limiter to 8700 rpm to stay into 4th gear.

My fifth run:
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14.34 seconds E.T. at 160 km/h partly damp track
tyres set at 1.9 bar
launch control 3900 rpm
30% at 9.9 second on minimax
150N/60F jetting at 950 psi
window switch at 3000-7900 rpm

To do something about the wheelspin in 1st and 2nd gear I decided to lower the nitrous charge to a 75 bhp shot but since I optimised the pulsoids for the 100 bhp shot I think I messed up the PWM signals because the engine felt a bit lazy and I didn`t get rid of the wheelspin. Too much torque down low. I also set the minimax at a 9.9 second ramp up time but that also didn`t help.

My 8th and last run:
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19.66 second E.T. at 120 km/h
tyres 1.9 bar
launch control 3900 rpm
30% at 9.9 second on minimax
200N/70F jetting at 900 psi
window switch 3000-7900 rpm

Did a few runs on a wet track but was all over the place on a nitrous charge so waited for the track to dry up. Went back to the original jetting.
By now I was so frustrated that I did all burnouts way past the staging sensor beams in an effort to make the tyres bite sufficiently for a better launch.
This was enough to piss off Kenneth the starting official eventually as I unsettled the electronic christmas tree logic sequence each time.
He came at me, opened my door; "one more time fella and you get a red code"! Whatever that may be lol.
I couldn`t be bothered as I noticed my car started to stutter down the straight. My bottle was empty, so was finished for the day.

So all in all had a good day considering the circumstances. Bettered my personal time to 13.9 sec E.T. but I feel there is still much more left in it.
The problem is now that I now have too much torque down low causing me massive wheelspin in 1st and 2nd.
I also need to do something about the wheelhop on launch. Perhaps some traction bars will alleviate this problem.
I`m open to all ears if anyone has a few good tips and tricks on how to improve my times further.

Cheers,

Paul.

dont no if it helps but i always lock the rear suspension and run about 20psi at most so could try droping the preasures even more

Yes I tried that. Unfortunately my launch control bogs the engine down when I try to do a burnout with the handbrake on. It`s set at 3900 rpm at the moment and I can`t change it at the track. I need to do that when I get back home.
But when I raise the launch control to say 5000 rpm it`s no longer of use on the track with nitrous, uncontrollable wheelspin.

If you can manage the following you'll run much quicker;

1) Launch in 2nd gear

2) Don't ride the clutch too much but try to avoid bogging the engine badly

3) Use the nitrous to achieve optimum launch acceleration

It's a balancing act and there's a risk of bogging heavily on nitrous (which COULD cause engine damage) but if you get it right it can be worth at least half a second.

My thought on reading the first post was reduce your start percentage but keep the same build up times.

As a side thought, when I was trying my new pulsoids yesterday I heard them pulsing when I first activated the nitrous but when I changed gear they didn't pulse as I had expected for each gear. Is there a setting on my Maximiser that I haven't understood that is meaning I'm getting the full hit on the subsequent gears? I'm hazarding a guess that I may have the reset function switched off and this is the cause.

If this is the case then maybe it's the same for the original poster.

EDIT: Just read my manual and yes, seems I need to set my reset to on so that it goes back to my starting % for each time I go off/on the gas. Problem is that I enjoy the ooomph it gives so need to see what difference it makes coming in at a smaller hit each gear now...lol.

That's why the REVO would be so much better, because you can start from ONE PERCENT (rather than 30% with the Minimax/Pulsoids) and instead of the car reacting to an INSTANT but 30% duration of 100% it ACTUALLY GETS ONE PERCENT and reacts accordingly!!!!

If you can't manage to take the REVO route yet, a step in the right direction would be the NEW Max Extreme, as not only does it allow a start power of just 20% (as all existing Max units have done) but it also has a NEW feature, that will enable the Pulsoids to work at start power levels of 10% or less. Whilst this is not as good as a REVO it's is the next best thing.

As per my post above, maybe you should switch the reset ON, as after the first gear change (on/off activation of the nitrous) the controller see's it then reactivates at whatever % the system was at when you came off the throttle to change gear. Therefore if you got to 100% in 1st gear, as soon as you change to 2nd it will be coming in at 100%. If you put reset to ON then it would (in your case) go back to 30% again. This can also be altered as you can add to or subtract the next gear start % after the first activation which in essence means you can 'dial out' the wheelspin in the lower gears by starting low then add more initial gas for each subsequent gear.

I'm unsure if this is the case/possible for the minimax as I'm basing the above on my Maximiser reset options so a Max Extreme is (as Trevor says) your next step to give you a lot more controllability.

Yes, I tried that once but the wheels still spun in 1st gear, changing into 2nd gear the car felt lazy and since this is an extremely shot gear I immediately have to shift into 3 rd and then it seems the car has to start all over again. I recorded lousy times with the reset on so I won`t do that again.

i have the opposite, using 100hp of nitrous, basically no jet in the X10 (i have a diesel by the way) using a minimax 50% power start, traction control turned off.. i get no wheelspin wotsoever

That`s the big advantage of rearwheel drive Ted. My front tyres are fighting for grip and if I overcook it at the launch I get lots of wheelhop.

ahh yes paul i forgot you have front wheel drive,funny enough im due for two new tyres on the rear, there just on the legal limit so im doing well for grip...

The technical scrutineers were really sharp on Tyres last Friday now you mention it. I heard some people didn`t make it to the race because of their worn tyres. There should be a minimum of 1.6 mm tread depth on the tyres this year in our streetlegal series cars, otherwise you will fall through.

There was a rather serious accident last year during a streetlegal dragevent due to a blown tyre so I think the officials were forced to raise safety levels.
Gone are the days were I saw bulges in the sidewalls of the tyres on some cars.

Using the 'reset' ON option on a Minimax certainly won't improve things but it would improve things if you had a Max Extreme.

You're right that the REVO would give you ALL the control you want/need but as a step in that direction, you could trade your Minimax in for a REVO/Max (which is capable of driving both Pulsoids & REVO's), which would provide you with MUCH MORE control over the Pulsoids and should you take the REVO route at a later date, all you'd need to do is buy the REVO's themselves, and switch the Max over to REVO use.

I was at the 4th and last round of the streetlegal drags in Drachten on sept 16th to try and better my times.
The 2nd and 3rd round were cancelled due to bad weather so this was my last chance this year to better my 13.9 sec. personal best.
The weather was good initially, cool and sunny and there was even a backwind.
The track however was a complete disaster. Tons of sand and dirt made it resemble a motocrosscircuit.
Not one of the competitors was able to improve on his times.

I made a total of 7 runs before I decided to make a hasty retreat to stay clear of fast approaching rainclouds.

Run 3

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100 bhp shot 200N/70F jets
minimax at 30%/9.9 sec ramp up
bottle pressure 950 psi
window switch activate nitrous in 2nd gear
2.2 bar tyre pressure
102 octane Aral ultimate fuel with very agressive cam angles and ignition curves on flashpro management
Rev limiter set to 8600 rpm
Launch control at 3600 rpm


Unfortunately my bottle heater striked when I started my runs. Try as I might, I couldn`t get it going again. Luckily on the drive to the track I already had the bottleheater activated to heat the bottle to 950 psi. During my runs the bottle pressure gradually lowered untill I was at 860 psi and then the car started to sound rough at high revs. There was even some bucking and sputtering at the topend as the mixture started to get excessively rich.

I was up against a guy with a chipped R32 Golf in this run. He jumped off the line with his fourwheeldrive but I quickly reeled him in at the end.
Did a 14.043 sec. E.T. at 171 km/hr with the car on the rev limiter in 4 th gear.

run 5

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Bottle pressure 910 psi
minimax at 5.5 seconds/30%

Was up against a German in a late model Beemer. Could barely hold him off.
Massive wheelspin in 2nd gear, obviously the 5.5 second ramp up time was too much for the tyres. Because of this had to shift into 5 th gear right before the finish line which annoyed me because that means a loss of time.
14.3 sec. E.T at 169 km/hr.

run 6

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Bottle pressure 830 psi
minimax back at 9.9 sec/30%

Had no chance against a fella with a 550 bhp Evo 3. By now I had to leave the starting line very carefully to bring the car up to speed but the fat nitrous mixture overpowered the tyres badly in 2nd gear. Car started to hesitate and sputtered at high revs.
I toyed with the idea of putting in a 60F jet but that would mean a 3.33:1 nitrous/fuel ratio. Not sure if that`s safe on a 100 bhp shot. So in the end I left everything as is.
15.05 sec. E.T. at 157 km/hr.

run 7

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Bottle pressure 770 psi

Decided to switch lanes as I was under the impression it was a bit quicker. Big mistake.
Had to leave the starting line like an 80 year old granny to get the car moving at all.
Massive wheelspin in 1st and 2nd gear. Could feel power drop off in 3rd gear on the rich mixture. Engine now started to run real bad at the topend.
Was up against the same Beemer guy that I was able to beat in a previous run. Not this time. Later I found out it was a diesel, oh the embarrassment.
Don`t bother with the time, I`m really ashamed.

So, that`s it for the 2011 season streetlegal drags. Was able to take 0.1 second of my previous best this year.
If it hadn`t been for the appaling traction on my home track I`m convinced I can take this car to a 13.5 sec E.T. I`ve seen others do it.

Oh well, more luck next year.