I understand internal combustion engine dynamics. I focused only on your statement that an engine is limited by a pretermined boost number - which is not true.
As I said, there are several areas of concern, boost pressure is one of them. If you are trying to promote a position where boost pressure is irrelevant, on a 17-year old engine with high compression pistons, you are either misinformed or irresponsible.
I'm sorry, this is definitely not true. The internal engine damage you cite, including the damage being attributed to BBSC superchargers is from rapid cylinder pressure spikes at incorrect moments in the combustion cycle.
The primary 'publicized' issue with the BBSC split second boxes is detonation, which led to engine damage, but this is not the only issue experienced by those who were running 12, 14, or higher psi of boost pressure. Some AEM-tuned high boost BBSC superchargers, where the split second boxes would not be a factor, experienced engine damage due to the high boost pressure on factory pistons.
While hotter intake charge temperatures will narrow the ignition timing envelope, the point is that the problems of other systems you cite were from faulty electronics causing pre-ignition - not 1.5 PSI higher intake charge pressure.
I will state it again, as you do not seem to be able to read my statements clearly:
9.5 psi of boost pressure is pushing the limits of an engine designed in the late 1980's, that probably hasn't been opened up in 17 years. 10.2:1 compression, 9.5psi of boost, no intercooling, no methanol injection, and no EMS capability to adjust to changing weather conditions. Given the lack of response to my earlier statement, it seems this engine is not even being monitered with a wideband oxygen sensor, or other safety devices.
Does this sound like an engine well suited for long term reliability to you? It doesn't sound like one to me.
I don't think we disagree that a cooler charge produces more power more efficiently. However, I can assure you that proper tuning including combustion timing has a greater affect than 50-100 degrees F of intake temperature.
You can run the engine with a higher air density, or you can throw a lot of hot air into the engine and retard timing - with these two options, you will make power. Which option sounds conducive to prolonged engine life, and performance?
I am not new here (you can see my join date of 2003 is prior to yours). I own both supercharged and turbocharged vehicles.
As I said, new to the
forced induction forum here on nsxprime; you were mis-stating my expressed concern for this motor, and insisted I had a perceived bias towards "the system I own", a turbocharger. I corrected you, to say
I have both supercharged and turbocharged the same NSX, and I am well aware of the benefits, and disadvantages of both systems. If you had been correct in your assertion, I would still have a supercharger installed, and I would be spouting about the dangers of turbochargers; instead a better system was released for the nsx, I recognized this, and purchased it for my car.
Rather than own different platforms with different forced induction solutions, I have run the different options on the same platform, back to back, at great expense and hassle, because the turbocharger is a better solution.
I personally feel that for the power range that most NSX owners are going for - which seems to be in the 100-150 hp increase over stock power - positive displacement superchargers like the ones used in the Comptech and ScienceofSpeed systems make the most sense.
I disagree; the nsx requires 400whp to truly reach it's performance abilities, this 400whp increase cannot be had with a high degree of reliability running higher boost pressures on a non-intercooled forced induction solution. Ideally, the engine will be refreshed, and a great deal of care will be taken to ensure a quality tune, a cold intake air charge temperature, and all supporting modifications to the fueling system, as well as required maintenance is performed; only in this way can forced induction, on a car which was not designed for it, be reliable.
8psi of boost pressure is a well-established figure in the nsx community; there are cars with considerable mileage, on stock engines, running this boost pressure. If you run a safe boost pressure, with a cool intake charge, a tunable EMS and a competent tuner, and are able to reach the 400whp figure, you will have a fantastic car. You are posting here because you "feel" a hot air supercharger makes more sense with this goal in mind?
My concern, and only interest in contributing to this thread, is the to see that proper information gets disseminated on these forums as it seems that there is much information on here accepted with out analysis.
I agree, information should be met with analysis; in your last post, you admitted you have not owned supercharged, and turbocharged, nsx's, and you have admitted your posting on this thread is based on your personal feelings, and not on facts. If you're concerned with unreliable information, you seem to be promoting the practice right now.
