Here's a post from themyst saying:
Quote:
Such precise methanol injection is so irrelevant given the wide adjustment range of fuel trims. When you can swing 34% in either direction, that leaves a HUGE margin for error. Which is why folks like me can run basic kits on this platform injecting 800cc of methanol at a low psi with no ill effects.
There is the issue of precise methanol distribution across cylinders, but once it mixes with the charge your bottleneck is the intake mani, and not the meth kit.
Aquamist is quality hardware and you are getting what you paid for. However, the inferior kits many of us have run for years also get the job done admirably.
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1) Precise metering of methanol is NEVER irrelevant regardless of the factory closed loop fuel control's authority range. For a number of reason. First, there is a finite amount of time required for the DME to respond to a sensor and then make the an adjustment to injector on-time. During this period of time, the engine can easily see a couple dozen engine events. During short period of time, the engine is either running rich or lean. The amplitude of this rich/lean spike will be proportional to the methanol delivery error. I know themyst has stated several times that he doesn't care about partial throttle performance and that may account for his feelings regarding poor methanol control. But most people don't treat the throttle like an on/off switch and can easily feel the benefits of careful methanol metering. Not only from the seat of their pants but also in how long a tank of methanol will last before needing to be refilled. Also, all these benefits of proper metering become even more important as power levels increase. If you are taking about supporting a 600+whp N54 with a conventional on/off methanol system, you really need a reality check. Because I can assure you, you will not be driving a car that powerful with just two throttle positions.
2) By intake manifold bottleneck, I'm assuming he is referring to uneven airflow distribution at high airflow rates. This is reality on just about every stock intake manifold used in high boost/big turbo applications. This is one reason a proficient tuner will target a richer-than-normal AFR in these high hp applications. This is to account for some cylinders running slightly leaner than others. So when you read the average AFR of two banks of 3 cylinders, the richer AFR target means that even the leanest cylinder isn't running lean. The only important aspect of the methanol system is to ensure complete atomization before the meth/air charge gets to the intake manifold. When the methanol is in the gaseous state, it can mix homogeneously with the air. Keeping the air/meth ratio (and octane) consistent. This is why we use 4 smaller nozzles, injecting just 1200cc, mounted well upstream in the intercooler end tanks. 2 of the nozzles are even mounted on the hot size of the FMIC which means the meth injected gets vaporized instantly. The meth injected from the 2 nozzles mounted on the cold side of the FMIC still have several feel to travel before getting to the manifold. This approach, which we were the first to apply on this platform, is clearly superior to injecting a single M12 (or two M7) in the charge pipe just before the TMAP sensor.
3) I agree that Aquamist hardware is better than the rest. Not surprising considering their motorsport history. That is why our PWM meth system uses their flow meter, filter, FAV, nozzles, line, etc,. They work better than the conventional kits when mapped properly. The only way I can see that using the cheap stuff as "admirable" if you take the money you save and giving it to charity. Because arguing that something worse is "good enough" really just says that either you or your application is discerning enough to appreciate the difference. Sorry but it's true. This isn't a matter of having "allegiance" to a certain approach/product. It's about knowing how things work and being open-minded enough to learn as new data is presented to you. I'll be the first person to admit that I didn't understand what the big deal was a few years back until I implemented our first PWM meth kit and saw how much better it met performance goals.