E30 top speed limiter

[Nick]

Are you talking about your E32? I have heard of them hitting over 175mph with the speed limiter removed.

{hard on}

Yeah they just keep pulling and pulling, and I delimited both of mine as soon as I had the chance.

I actually went so fast in my 88 that the windshield trim flew off and the window cracked. I bottomed out the speedo (170) and the tach was still flying higher.
The 94 is definately faster, but I haven't beat up on it too much because it's much nicer.

It's eerie how stable the car feels at such high speeds.

Oh yeah, I only paid $2500 for the '88 750... :)

[euroshark]

Well... I'm not saying I'm right, I'm just going with what I think is right. If someone can do this with math, please help because I'm not about to crack open a book to help me remember this stuff! lol

The speedo sensor is triggered by the diff I think. The E28s do it that way at least, so if your tires are larger or smaller in diameter than the factory size, you will see variations that change exponentially. Mechanical or electronic doesnt matter because they are triggered by a rotating mass that is directly connected to the wheel and tire. If the wheel rotates slower for a given speed because the tires are larger than stock, then the speedo will be affected more and more as speed increases (it will show slower than your actual speed), and with smaller tires it will show faster. At least that's my understanding... I'm no math major, but my gf is :drink:

[nando]

Not raining on your parade, but what speed is the speedo off by 3-4mph? I ask because when speedos are off, it's exponential when they are triggered the way these cars are. 3-4mph at 45mph could be 10mph, 15mph, maybe more at an indicated 150mph.

Nevertheless, thats impressive!!! I'm assuming you were near sea level? At altitude ours cars feel weak... going down 1000 or 2000 feet feels like you just got a supercharger!! If your 325i showed 150, maybe my 335i will be able to touch 160 indicated.

Not that I have the balls to try it on the highway...

I don't think E30 speedos work that way. mine is actually decently accurate at 60+, but at an indicated 25 it's almost 10mph off! I think BMW just adds 3-5mph across the whole range to keep you out of trouble. remember, these speedos are not mechanical, the mechanical ones definitely are less accurate at higher speeds.

[Jesse30]

145 mph slight downhill

'89 325i, 5 spd, 3.73 open

10/88

[euroshark]

Originally Posted by Nick View Post
A 187MPH reported top speed in a car that cost me less than $10,000...FTMFW.

Are you talking about your E32? I have heard of them hitting over 175mph with the speed limiter removed.

{hard on}

[EtaSport]

my 2.7i mess ran the speedo out with a 173 ecu. my m50 stops at 135, or 128 probably with corrected speedo.

[SpunkyE30nOk]

I've hit 135mph indictated on the speedo and it was still accelerating with about 700 rpms to go before redline..I think she'll hit 140 no probs

prod 12/87/stock minus cat delete/K & N filter
ecu 173 i believe, 5 spd manual

[92 mtechnic cabrio]

yeee 4.10 ftw.

I don't know how accurate my speedo is, but when I run out of gear, bouncing at 7k RPM, I'm doing a speedometer indicated 143mph.

[german g]

A 187MPH reported top speed in a car that cost me less than $10,000...FTMFW.

nice!!!

[pineapplegti]

throw me the keys.. 160 feels the same as 150 :)

[euroshark]

Well damn, that is pretty impressive then!!

[pineapplegti]

Not raining on your parade, but what speed is the speedo off by 3-4mph? I ask because when speedos are off, it's exponential when they are triggered the way these cars are. 3-4mph at 45mph could be 10mph, 15mph, maybe more at an indicated 150mph.

Nevertheless, thats impressive!!! I'm assuming you were near sea level? At altitude ours cars feel weak... going down 1000 or 2000 feet feels like you just got a supercharger!! If your 325i showed 150, maybe my 335i will be able to touch 160 indicated.

Not that I have the balls to try it on the highway...

my grandfather has a radar gun(used for our landspeed car) that ive played with and 3-4 mph off is what we got at 60 on up to 125 (back when it was limited.) now im not saying it cant be off in the upper ranges but i do know that the speedo was pegged and engine was maxxed :)btw my tires are a bit undersized as well

[backtrail69]

well my 325i with stock motor stock exhaust 3.73 and ebay chip did 150 no prob, per the speedo of course which is about 3-4 mph off (fast) also the car has 198k on it lmao

Just thought id point out that undersized tires effect your speedo ALOT.

[euroshark]

Not raining on your parade, but what speed is the speedo off by 3-4mph? I ask because when speedos are off, it's exponential when they are triggered the way these cars are. 3-4mph at 45mph could be 10mph, 15mph, maybe more at an indicated 150mph.

Nevertheless, thats impressive!!! I'm assuming you were near sea level? At altitude ours cars feel weak... going down 1000 or 2000 feet feels like you just got a supercharger!! If your 325i showed 150, maybe my 335i will be able to touch 160 indicated.

Not that I have the balls to try it on the highway...

[pineapplegti]

Niiice... I wonder what the 335i will pull with a 3.25LSD? Maybe 150? Im pretty sure the gearing is good to over 160, but I'll have to plug it into the gear calculator.

I hit an indicated 145mph in my Alfa, stock 2.5 with 155hp :)

Maintained it too, pinned at 6000rpm (rev limited at 6300) for around 15 - 20 miles through south western Colorado.

well my 325i with stock motor stock exhaust 3.73 and ebay chip did 150 no prob, per the speedo of course which is about 3-4 mph off (fast) also the car has 198k on it lmao