130 mph - 150 mph

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Humboldtson

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I am new to all this. Just joined the other day. So I hope I am doing this right. In looking to purchase my first coupe. I noticed that some of the speedos go to 130 mph and others 150 mph. ( I am not sure if this the case in the 3.0csi ) Why? Thanks. Brett
 
If a speedometer is used for km and miles and the
top speed must be the same and also a multiple of 10
then given that a mile is 8/5 of a kilometer, the top speed
mark in miles must be a multiple of 50.

150 mph works fine, 130 does not.
 
csi speedo

Stevehose said:
I went 110 once (allegedly) and had more pedal available.
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I hit 157mph, without knowing I was going that fast! My csi has 5 speed, changed the dif. From 355 to 325, 17 inch rims all ads up to an incorrect Speedo. Had car in to check HP on dyno I was asked if I would like a Speedo checked. So to check Speedo the mechanic pushes a button at 40mph 50mph 60mph all the way to 100mph it records the correct actual speed. That’s when I found out the day I decided to open it up, and it started to float at 130mph I had some concerns that shocks need to be upgraded, after calculation found out I was going 157 mph. My csi is not stock.
 
Once the coupe reaches 110 or so, the front end lifts and flutters disconcertingly, as if the front end will take flight. This is where a front air dam comes into play and just not eye candy.
 
I hit 135 once, and the front end was starting to float because of no front air dam. Based on engine rpm the car will go 165; it still had oomph at 135. Never been that fast since.
 
Humboldtson said:
110-130-150. All fast to me. My question remains. Why do some of the speedos in 3.0cs go to 130 mph and others go to 150 mph. Was this an option a trade or what?
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These lower numbered speedos may have been fitted to the 2800CS or the 2.5CS. Both of these coupes had top speed in the 120's.
 
I tested my csi up to nearly 200Km/h, but not to recommend. All I was thinking about was "Do not crash with this car!" You are so dead if anything goes wrong.
 
Reading comprehension seems to be lacking today :lol:

To the OP, probably just something as mundane as what the order placement was at the time from BMW to VDO. Got a breakdown by year?
 
...all with a grain of salt

...optimistic speedos and the aerodynamic/dual carb'd wall....thought I'd chime in on this fun thread. I have tried to find MY 'max' ...;-)

Agreed, coupes get 'lighter' in the front above 105mph, air dams exist for a reason.
Take speedo reading with a grain of salt, having a GPS will tell you the 'truth'.

I have taken mine out for a 'tests' before: broke and sustained just over 220kph (I have a Euro speedo = 136 mph). The car was confident and stable with all its go fast mods, my air dam was not on at the time. However, it had max'd out under redline (5500rpm). I think i had hit my car's power/aerodynamic wall. I assume this is where having the big triples would start demonstrating their difference over the dual 38s; up in the very high rpm range. Seemed my carbs just couldn't keep up (motor is "built") and ran out of top end pull at 5500rpm/220kph. I have a CR box with a 3.45 LSD on 14" 205s.....

So, take a GPS with you for a true reading, my speedo read 220kpm or 135+mph...my co-pilot called out the mph GPS readings as we consumed the hwy.....

GPS reading = 115mph

I think the coupe speedos can be a bit optiomistic....

Another CS max speed tale:
My brother in his old CS racer wrapped the speedo all the way around to the 5 mph mark on the Fontana/CalSpeedway oval once. We guessed 150mph+, then he ran out of straight away... car had a built M30 race motor, dyno'd 275hp at the wheels with triple 45s, 5spd OD box, either a 3.91 or 4.2? diff that day, and either a pair of large cajones or a few loose screws) Its funny footage watching the needle do all the way around... and he still gets passed by some others.....

Above all, be cool and stay safe coupers...

"..this message will self distruct in ....10...9 ...8..." ;-)
 
Sure with a 3.91 diff the speedo would show approx. 17% too much due to the mech speedo drive in the gear box... So anything about 150 would then be 125 mph...

A well set up but still bone stock Si and more so the CSi will reach a healthy 137-140 mph GPS with a 5sp OD at 5,500 rpm in 5th which is near optimum since the peak power is rated at 5,500 rpm for the D-jet engine (Euro spec.)

To my knowledge all E9 had 150/240 speedos, but the 121 coupe had the 130/220 speedos. Can someone confirm?
 
So this was my first "thread". Love the dialog. Been a member almost a week and have learned a lot. I am just starting my hunt for a coupe so I am sure I will have more questions.
 
DerSchwede said:
I think driving an E3 at +120 mph is quite comfortable given a well setup chassis of course ;-)
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My car rides very nice at high speed as well. But, I don't think even the "best of the best" set up chassis would spare your life in a high impact crash sitting in E3/E9! That's simple facts. Drive safe folks! :-)
 
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