Sound

[PRB]

Watching the NASCAR practice at Sonoma. They have a camera inside Harvick's car. As he's going "roundy roundy", and shifting gears, you can hear the obvious sound of the engine. But there is another sound, rising and falling with the engine RPM. Sounds like mechanical noise, very high frequency whiny sound. I'm guessing transmission, because it sounds similar to the "jerky whiny" sound you hear on pit road from the "in-car" as they accelerate out the pit box. Amazing those things don't shed parts half way through the race. Well, some do I suppose. In the words of Ken Schrader when asked "what happened" -- "one of those important pieces that go around real fast broke"...

[Daveroo]

gotta love Schrader,like his comment after hitting the wall at daytona...he was on that show that had beswick,schrader,waltrip and benson...kenny says...ya know,soon as the car turned...i said to myself.."this is gonna hurt".....

[Daveroo]

oh fer cryin out loud,id forgotten what i was going to say...dont they use a gear drive for the timing,rather than the chain?..if thats it,then yes those gear drive units whine some thing fierce...i can also ask allen..he builds engines for JGR,he was building the engines for busch in the xfinity series.

[PRB]

Somebody on TV once said the reason the transmission sound is "jerky" while coming up through the gears is that NASCAR transmissions use straight gears, as opposed to our cars that don't. Don't know enough about that to comment on it, but it's interesting if true. There must be some advantage to using "straight gears", since that jerky sound seems to imply greater stress on the transmission. Sounds pretty cool anyway... Love Schrader. Too bad he's not racing anymore in NASCAR. His track (Pevely, MO?) is not far from where I live.

[stansdds]

It's for transmission durability with the very high horsepower engines used in race cars.

http://automotivethinker.com/transmi...rs-vs-helical/

[PRB]

Very interesting. It makes sense that the helical gear system would impart loads in two directions upon acceleration, as opposed to the staright system. All this reminds me of the unique sound of a P-47 while taxiing, where you can clearly hear a large "mechanical component" to the sound. Good stuff. Thanks stansdds.

[Daveroo]

Somebody on TV once said the reason the transmission sound is "jerky" while coming up through the gears is that NASCAR transmissions use straight gears, as opposed to our cars that don't. Don't know enough about that to comment on it, but it's interesting if true. There must be some advantage to using "straight gears", since that jerky sound seems to imply greater stress on the transmission. Sounds pretty cool anyway... Love Schrader. Too bad he's not racing anymore in NASCAR. His track (Pevely, MO?) is not far from where I live.

well....you got an extra bedroom for me?...and can you push a ...well big guy around?.....we go to Pevely...your treat ofcouose.....

oh and btw...got airfaire too?...

[PRB]

Ha, I got three bedrooms, but only one is a bedroom! Here's a pic of Pevely Race Track, just off I-55. When I first moved to this State I lived very close to this place, in the mid-1990s, but wasn't interested in racing then. Looks like a dirt track. Don't know what he races there. I've only been to one actual race, and that was years ago. A sprint car race in Hanford, CA. I remember being very surprised that I could feel the ground shake from the stands when one of those things crashed and rolled a couple times.