Physics/mechanical: Can a different muffler affect RPMs at speed?

[InlineFour]

Originally posted by: Iron Woode

Originally posted by: FightingChance

Originally posted by: Evadman
Unless the muffler is ground into the shape of a smaller gear (less teeth) and put in the transmission, the RPM at speed with be exactly the same.

This is probably one of the guys that thinks adding a wing on a FWD car is a good idea.

Not to nitpick, but increased traction in the rear from wing downforce could also benefit a FWD car, just not by pressing down on the drive wheels (it would help prevent oversteer though)

But I always thought wings were pretty useless for the street, you need to be going pretty well to reap the benefits.

what downforce? At 40 mph?

no spoiler is doing anything usefull at under 130 mph.

unless you're driving next to a tornado. 😀

 

[shoRunner]

the only thing it could possible change would be throttle position, even if the engine wasn't in the car and hooked directly to the gearbox without any sort of exhaust restriction the rpm @ speed would be the same as they are directly related.

 

[FightingChance]

Originally posted by: Evadman

Originally posted by: FightingChance
Not to nitpick, but increased traction in the rear from wing downforce could also benefit a FWD car, just not by pressing down on the drive wheels (it would help prevent oversteer though)

Limited benefit until ground speed is > 80 MPH IIRC. I would have to break out my calculator and know the wing characteristics like angle of attack and such (which actually make a big difference). There is some good info at Chassis Works, as they design functional downforce inducing wings for race cars. I looked into it for a project I am working on.

Pretty much every car in the US is designed to go into understeer before oversteer to keep lawers happy. Of course, RWD cars can induce oversteer with some application of the go pedal. E brake doesn't help the FWD.

Putting a wing on a Civic will only slow it down. By pushing on the rear, the nose will pivot roughly on the centerline of the front axle, thus raising the nose into the air. This allows more air under the front of the car (thus lifting it) and providing less grip on the axle that in a FWD does not only the steering work, but also provides for forward motion.

Even the largest wing that Chasis Works manufactures will only produce about 200 lbs of down force at 150, with something like 8 lbs of drag (might have been 11. It has been a while). the force goes up exponentialy with speed, so at 300, the wing would be in the 800 lbs range. I was looking to add 200 lbs of downforce at 120 with 2 canards for my project, but the canards would have been a total of 8' wide, making my vehicle about 10' wide. Obviously, this was not a solution 😛

Well said :thumbsup:

 

[Kenazo]

Originally posted by: Iron Woode

Originally posted by: Kenazo

Originally posted by: Iron Woode
no spoiler is doing anything usefull at under 130 mph.

This thing looks useful sitting still!

WTF does Laura Croft have to do with this?

Ohh, but this looks interesting:

http://www.mopo.ca/2006/04/most-expensive-wagyu-beef-sandwich-148.html

Huh? When I click on the link I get a pic of a K car with a plywood wing.

 

[Iron Woode]

Originally posted by: Kenazo

Originally posted by: Iron Woode

Originally posted by: Kenazo

Originally posted by: Iron Woode
no spoiler is doing anything usefull at under 130 mph.

This thing looks useful sitting still!

WTF does Laura Croft have to do with this?

Ohh, but this looks interesting:

http://www.mopo.ca/2006/04/most-expensive-wagyu-beef-sandwich-148.html

Huh? When I click on the link I get a pic of a K car with a plywood wing.

I just get a listing of stuff from mopo.

🙁