225 top speed is limited by what? Drag or rev limiter? And what is it? (more)
02-09-2002, 10:59 AM
#1
New Member
Thread Starter
Join Date: Jun 2000
Posts: 122
Likes: 0
Received 0 Likes
on
0 Posts
225 top speed is limited by what? Drag or rev limiter? And what is it? (more)
Driving down a long slow hill with a steady 30 mph Santa Ana wind behind me I just found myself doing 145 - with the top down. Yes, very stupid, but there you go. From a power point of view the car felt like it had plenty left, and I only slowed down because I reached my exit.
I had always believed that the 225 topped out in the low 140's, and assumed it was rev limited, but this now doesn't seem to be the case.
To save me from mortal wounds by trying to find out for myself, can someone tell me what the actual top speed is?
I had always believed that the 225 topped out in the low 140's, and assumed it was rev limited, but this now doesn't seem to be the case.
To save me from mortal wounds by trying to find out for myself, can someone tell me what the actual top speed is?
02-09-2002, 01:42 PM
#5
Member
Join Date: Mar 2000
Posts: 3,123
Likes: 0
Received 0 Likes
on
0 Posts
Power drops after 5900 rpm, thats why it felt good at 140.
If you remove the speed limiter you'll get about 152, but the power output is dropping and power requirements increasing. In the coupe you can smell the effects of all the heat the turbo is putting out. Next time you get the car to speed, test your brakes. I think you'll be shocked at what you lose compared to 100 mph.
02-10-2002, 06:09 AM
#7
Member
Join Date: Apr 2000
Posts: 4,008
Likes: 0
Received 0 Likes
on
0 Posts
Good point on the brakes. It's that pesky mv^2 thing.
Twice as much energy @ 141 than at 100 mph.
Even a moderate braking from a buck forty will max out most brakes. The C5 Vette, with much larger brakes than a TT, and better weight distribution during braking, noticeably runs out of brakes with a fairly hard stop(-.5 g or so) from 140. Been there.
A TT @ -.5 g has about 70-71% on the fronts while the C5 has about 61-62% then. It's probably a close assumption that the braking is about the same F/R ratio.
Trying to max brake @140 would probably result in almost no brakes by the time you got to double digits. Have lots of clear road ahead if you are going to go that fast.
Even a moderate braking from a buck forty will max out most brakes. The C5 Vette, with much larger brakes than a TT, and better weight distribution during braking, noticeably runs out of brakes with a fairly hard stop(-.5 g or so) from 140. Been there.
A TT @ -.5 g has about 70-71% on the fronts while the C5 has about 61-62% then. It's probably a close assumption that the braking is about the same F/R ratio.
Trying to max brake @140 would probably result in almost no brakes by the time you got to double digits. Have lots of clear road ahead if you are going to go that fast.
Thread
Thread Starter
Forum
Replies
Last Post
Mirror|rorriM
A4 (B5 Platform) Discussion
7
06-12-2002 04:51 AM
4.2MingBlue
A6 / S6 (C5 Platform) Discussion
14
12-05-2001 06:06 AM
MAC225
TT (Mk1) Discussion
15
12-07-2000 12:13 PM