NITROUS OXIDE ( nos / n2o ) advice forum

LOL!!! No, it's nothing that's within my control at the moment. Long story short, the fuel pump can't keep up with a 50 fuel jet. The pressure becomes erratic at the point where I'd get my "misfire", therefore the engine was lean at high RPM.

It also explains why the car felt weak on the nitrous. Also, the problem gets much worse with the cut out open. I'll need either a larger pump, or better yet a dedicated fuel system for the nitrous. I have a FPR with a boost reference so I can just get an EFI pump and a tank. So I've hit the wall again with the Sonic so I'll stay at 25 hp since that worked great.

OK well that is a good opportunity to promote the fuel flow test that I detail in my book;

1) Turn off the nitrous bottle

2) Disconnect the fuel pipe from the Crossfire and run it into a catch tank

3) Connect a pressure gauge to the fuel supply system

4) Carry out a test run while monitoring the fuel pressure gauge

5) If the pressure drops by only a few psi continue the run for exactly 10 secs if possible and 5 secs if not.

6) If the pressure drops by more than a few psi and continues to fall, terminate the test run.

7) In the event of a minimal pressure drop, measure the quantity of fuel in the catch tank/bottle, then repeat the test but this time in neutral and at idle.

8) If the quantities from both tests are close to being the same, you can continue to go forward and use the system.

These instructions 'should' be followed before using a nitrous system but as 99% of vehicles have fuel systems that can flow approx. 30% more than they need NA, we don't normally bother or advise it unless;

1) We have reason to suspect the fuel system won't be up to it
OR
2) We are using jets that are capable of increasing the power by more than 25% of the NA power

I performed that same test before, but I would get different results in fuel quantities because the fuel pressure increases with boost by the ECM. And with the fuel outlet pipe exposed to normal atmospheric pressures, the differential pressure and thus fuel flow is greatly exaggerated compared to the same test at idle.

P.S.

My car is already tuned for 40% excess power from stock without nitrous. Add an additional amount of power with the nitrous and the fuel system will be taxed even further.

well done for working out what the problem is

now surely the aim is to work on curing the problem... and eventually feeling the hit of the whole fruit

to explain the hit of the whole fruit https://www.youtube.com/watch?v=bR1SEGyVVe0

Then the best course would still be an auxiliary fuel system so that the factory components remain as stock as possible. This way, I can simply transfer all of the nitrous parts, along with the fuel kit, to another vehicle.

EEEEEEEEEAR TO EEEEEEEEEEEAR my friends! The WoN grin is EEEEEEEEEEEAR to EEEEEEEEEEEEEEAR right now!


SONIC POWER IS REEEEEEEEEEEAL NOW!!!!

I need more details

LOL not yet, it's not ready YET! This car is the biggest PIA on nitrous but it did show a glimmer of hope so I'm not giving up.

Just to update:

Apparently, AEM UEGO AFR gauges just dont jive with the max extreme's voltage scale. The AEM voltage scale is very narrow (still 0-5v) with 0 being 10:1 and 5 being 20:1, whereas the maxy is 4:1 @ 0v to 24:1 @ 5v. No matter what I did with the adjustment pot, I couldn't get them to work together.

Now I need a compatible wideband unit, but I need to know which one will work.

My Maxy may be defective: I tried EVERY possible way of getting an RPM signal for the window feature and NOTHING worked. Even hooking up to the ignition coil of a spare 2 stroke engine produced no results. I'll have to return the unit for inspection/repair.

Hi Alex, it's HIGHLY UNLIKELY that the Max is at fault, especially with respect to the RPM feature, so before you do anything further in that regard, might I suggest you give Lewis or Dave a call, to ensure you everything correctly set up and connected.

Similarly the AFR should NOT be a problem, as long as the correct settings are selected, so again I'd suggest a quick chat with lewis or Dave on that one as well.

The reasons I very much doubt that the Max will be at fault in these regards are;
1) We've NEVER had a Max fail in ANY specific way as you're anticipating
2) As far as I'm aware the Max has the ability to work with every type of AFR unit
3) we often encounter situations like this and yet we've always found the problem to be something other than 'A FAULT' with the Max

Sorry I can't give you absolute answers to the issues but I delegated the donkey work of creating the Max to one of my EX employees and unfortunately he was the only employee who had FULL knowledge of all aspects of the Max features. Since he left the 3 of us Dave, Lewis and myself have been trying to learn the knowledge we are missing (while also learning about the new features I've added in the years since he left), to ensure we can provide the guidance customers require.
In most cases Lewis has the greater level of knowledge but thankfully the knowledge they both have isn't the same, so between them they can usually provide the assistance required.
Unfortunately, Dave doesn't work Tuesdays so if Lewis can't assist you, you'll have to wait until Wednesday, which hopefully won't be too much of an inconvenience.

I've sent emails about my issues about the AFR with no response as of yet. I'll call tomorrow and find out the info about the Max set up issues. It's merely my frustration and having to burrow myself under the car after dicking around under the bonnet for hours had me infuriated.

I also HIGHLY doubt that there is something wrong with the unit itself, I just need to find the means to TEST the rpm feature.

Also, no matter what I did with the pot on the Max for the input signal. I still think that it's the AEM sensor output scaling. It's too bad that there isn't anyone on here that has a resolution for this because I've searched the forum high and low.

BTW, the issue with the misfire was actually the OPPOSITE of my earlier findings, in that the car DUMPS endless fuel at the top end. I mean it's a LOT of fuel, so I need the AFR loop to take away the excess fuel. Furthermore, the excess fuel in the tune is to take away heat due to the 23 psi of boost spike that the car makes and 29 psi boost spike on 25 shot of the gas!

What's funny is when I did the shutdowns during the misfire to see what the plugs showed, revealed a rich mix but not a SUPER rich mix like the AFR meter is reading.

Ok, I've made SOME progress with the Maxy in that the AFR choices 1 & 2 are SELECTABLE SCALES for use with different AFR meters. This is NOT clear in the instruction manual and needs clarification in the future. What I thought was that the AFR 1 & 2 was some sort of operating window where the Maxy is to keep the AFR within during nitrous use.

Still, I can ONLY calibrate it up to a point where the AFR meter and the Maxy are 1 full point off from each other. At the very least, I can work with that error margin.


Furthermore, I further tested the Maxy RPM input and I DID find a discrepancy with the unit. Now bear in mind that I did purchase the unit USED from WoN so the fault must've been from the previous owner that was overlooked during testing because I've never attempted to connect it prior to the last few days. There is a PCB fuse that I traced for the white/blk striped wire and there is an OPEN across that fuse. Here is the Photo:

Still working on the Sonic's troubles breaking up at high rpm on nitrous. I've done ENORMOUS amounts of work trying to figure it all out until recently when I found my best reasonable guess: EMI (Electromagnetic Interference).

I've conducted numerous tests, and I've hypothesized that the voltage leakage through the rubber ignition boots are causing the break-ups. My supporting conclusions further verify my hypothesis, but only flawless nitrous runs will prove this once and for all.

I will be calling Magnecor to see if they can create something for me.

I WILL HAVE A MENTAL NITROUS SONIC!!!!

Very glad you figured that out Alex and I'll pass on the info to the team to ensure they are also familiar with it in future.

Hey, Trev!!! Glad to see ya popped over on the forum!

Yes, I JUST got off the phone with Magnecore and they are going to assist me with my problem and I am going with FAR MORE POWER COILS and the race wires to go with them.


I tested these coils in a coil-on-plug setup, but the increased voltage made things worse and misfired earlier than the stock coils. This is what lead me down the rabbit hole of the root of the problem.

For anyone reading this thread, the more dense the cylinder charge, the more resistance to cross the spark plug gap. And since the path of least resistance is through the boot, then that's where the spark goes. The more powerful the ignition, the worse the problem!


BTW, I don't think anyone has attempted this on this engine. So I claim the first to do so!


My new mounting is around here:

Reading and digesting