I am in the market for a used NSX -- my preferred year is '94. NSXs are pretty rare in Denver, probably fewer than 20 in all of Colorado. I have driven two so far, in my quest. One of them was so ratty it deserves no further comment. The other looked gorgeous, however the engine sounded very rough to me -- nearly, but not quite, as rough as the first ratty one. Here is where familiarity, or lack thereof, is important.
I'm a mechanical engineer by training. I am aware that a 90 degree V6 is not innately balanced on all four of its primary and secondary forces and couples. I also know that above idle, the roughness disappears (actually it is absorbed by the motor mounts) and is of no consequence. I also know, intellectually, that the lost motion devices in the VTEC mechanism can be noisy, and can sound like loose valves. But intellectual knowledge and seat-of-the-pants experience are two very different things. My former Integra GSR did NOT have a noisy valve train, but its VTEC design is several years newer and had eight fewer valves.
What bothered me most about both examples was the gear box. My old Integra had the sweetest, smoothest shifting 5-speed I have ever experienced -- even smoother than the 61 Porsche 356B I had as a kid. The Integra also had to handle 100 lbs-ft of torque less than the NSX. Both NSX gear boxes were notchy and both had very weak to non-existent third gear syncros. I got chewed out by the forum Nazi for starting a new thread on that topic a few months ago. What I got out of that exchange, however, was that the gearbox's should have strong syncros, and should be 'smooth,' but I still have no idea of how smooth.
I would be deeply indebted if some NSX owner in Colorado, or passing through Colorado would have some time to stop and talk with me for a while and help me sort through some of these things, and just generally shoot the breeze about NSXs in general I'll buy lunch. I can meet you just about anywhere at your convenience. TIA
Mark
I'm a mechanical engineer by training. I am aware that a 90 degree V6 is not innately balanced on all four of its primary and secondary forces and couples. I also know that above idle, the roughness disappears (actually it is absorbed by the motor mounts) and is of no consequence. I also know, intellectually, that the lost motion devices in the VTEC mechanism can be noisy, and can sound like loose valves. But intellectual knowledge and seat-of-the-pants experience are two very different things. My former Integra GSR did NOT have a noisy valve train, but its VTEC design is several years newer and had eight fewer valves.
What bothered me most about both examples was the gear box. My old Integra had the sweetest, smoothest shifting 5-speed I have ever experienced -- even smoother than the 61 Porsche 356B I had as a kid. The Integra also had to handle 100 lbs-ft of torque less than the NSX. Both NSX gear boxes were notchy and both had very weak to non-existent third gear syncros. I got chewed out by the forum Nazi for starting a new thread on that topic a few months ago. What I got out of that exchange, however, was that the gearbox's should have strong syncros, and should be 'smooth,' but I still have no idea of how smooth.
I would be deeply indebted if some NSX owner in Colorado, or passing through Colorado would have some time to stop and talk with me for a while and help me sort through some of these things, and just generally shoot the breeze about NSXs in general I'll buy lunch. I can meet you just about anywhere at your convenience. TIA
Mark
deep in the Chicago winter. 
