| Shock dyno comparo |
Subject: Shock dyno comparo by ghoffman on 2008/7/6 15:06:47 Ok, here are 5 force-velocity and Force-displacement plots we ran on our dyno. These are all Corvette C5/C6 rear shocks, 5 different brands, which do you think is the best, and which one actually works the best on the street and/or track? What curve do you think is the worst? What do you think causes the hysteresis in some of these curves? Without a dyno, you are only guessing, and real world (road race and steet) has lots of greater than 3 in/sec velocities. Body roll, squat, dive, etc is the less than 3 in/sec stuff, but bumps, curbs, ripples are much greater than that and 8-10 in/sec is very common. An interesting thing is when I was at Penske last summer, it was mentioned to me that a tolerance variation of .0005 inch (yes, 1/2 a thousand) could cause 20-30 pounds (depending on the valving) on the dyno, and that is why each shock has to be tested and if not within spec, it is made to be correct. If the super quality CNC parts in a Penske can cause that kind variation, what do you think you get in a mass produced cheap imported shock? The first plot is Force-Velocity, the second is Force-displacement. There were many details that we have not discussed, but I will later (things like not holding gas pressure, leaky seals etc) We have seen new GM T1 shocks that flat were not working (shown here): [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockT1bad.jpg[/IMG] [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockT1badFD.jpg[/IMG] The rest are shown here, brand names deleted. Brand A [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockbad.jpg[/IMG] [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockbadFD.jpg[/IMG] Brand B [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shocksoso.jpg[/IMG] [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shocksosoFD.jpg[/IMG] Brand C [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockgood.jpg[/IMG] [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockgoodFD.jpg[/IMG] Brand D [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockMfullhard.jpg[/IMG] [IMG width=640]http://i67.photobucket.com/albums/h287/gshoffman/Corvette%20shocks/shockMfullhardFD.jpg[/IMG] |
