06-10-2007, 03:18 PM
|
 |
Registered User
|
|
Join Date: Apr 2007
Location: Ste Julie Quebec Canada
Posts: 105
|
|
|
Speed versus RPM
At 100 Ks (64MPH) per hour I am at 3500 RPM in my 92 Spider in 5th gear
Does that sound right
I was passing a lot of cars at that speed and had the feeling I was going a bit faster than 64 MPH
14" wheels
Daydreaming or what
__________________
1992 Alfa Spider Green with Tan interior 
1989 Porsche 930S RUF 2008 Honda CRV EXL Green Tea with Grey Leather
|
06-10-2007, 03:25 PM
|
 |
Slacker
|
|
Join Date: Mar 2006
Location: Northern NY, USA
Posts: 6,475
|
|
|
1st gear @ 1000 rpm: 8.5 km/h
2nd gear @ 1000 rpm: 14.8 km/h
3rd gear @ 1000 rpm: 20.9 km/h
4th gear @ 1000 rpm: 28.8 km/h
5th gear @ 1000 rpm: 35.6 km/h
Take into consideration that your tach could be well off, so the above isn't gospel, just reference.
3500 @ 64mph sounds about right, and something right around 41-4200 at 74mph.
|
06-10-2007, 03:34 PM
|
|
Registered User
|
|
Join Date: Aug 2005
Location: Camlachie Ontario Canada
Posts: 1,120
|
|
|
I refer to Alfa product bullettin PA381500000000 Jan 86 for Spider 115. USA Version Graduate, Veloce, Quadrifoglio. This is on page 36 (RPM vs Road Speed Graps for gears 1 thru 5)
Fifth gear, 100km/h, 2800rpm
Fourth gear, 100km/h, 3500rpm
My 87 Quad confirms these points.
I would take it that your 92 would follow the same curves, as such you are going faster than your spedo indicates.
From the same curve I reference 3500rpm in 5th gear is 130km/h
Best regards, Elio
Last edited by Elio Comello; 06-10-2007 at 03:38 PM.
Reason: mistake
|
06-10-2007, 03:34 PM
|
 |
Registered User
|
|
Join Date: Nov 2002
Location: Northampton, MA
Posts: 1,163
|
|
|
5th gear = 22mph/1000rpm
3500 rpm = 77 mph
__________________
92 Spider Veloce
71 TwinSpark Spider - Soon to be 4 Sale
|
06-10-2007, 04:15 PM
|
 |
But Mad North-Northwest
|
|
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 2,062
|
|
The smart money is on both the speedo and the tach being off. Fortunately they're fairly easy to adjust. Details here:
How to fix your slow reading speedometer or tachometer on 91-94 Spiders
Best to calibrate them independently rather than to use one to calibrate the other. Use a GPS for the speedometer and a digital voltmeter or engine analyzer with a tachometer function for the tach.
__________________
Tom
1991 Spider
1987 Milano Gold
|
06-10-2007, 05:02 PM
|
 |
Senior Member
|
|
Join Date: May 2003
Location: Oakville ON
Posts: 1,753
|
|
 Quote:
Originally Posted by Paradiso
5th gear = 22mph/1000rpm
3500 rpm = 77 mph
|
__________________
Ken Lee
Oakville, ON
1974 GTV 2000 - Ruby (I'm never selling this one, honest!)
1973 GTV 2000 - Rowdy (or this one I hope)
|
06-10-2007, 05:34 PM
|
 |
Alfa Poor in KY
|
|
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 3,807
|
|
|
Paradiso is right on the money. 22.14mph per 1000rpm in 5th. 82-94 Spiders....manual only
The 4.56 is 20mph per 1000rpm in 5th. 81 and earlier spiders.
Best Regards,
John M
__________________
1978 AR Spider Veloce 2000.....the first and still here
1984 AR Spider Veloce............the second & gone to the parts bin
1992 AR Spider Veloce............the third and still here
1991 AR 164L........................traded on the SS
1965 AR Sprint Speciale..........in boxes.
|
06-10-2007, 06:12 PM
|
|
Senior Member
|
|
Join Date: May 2003
Location: Oakville ON
Posts: 1,753
|
|
Thanks for straightening me out 
__________________
Ken Lee
Oakville, ON
1974 GTV 2000 - Ruby (I'm never selling this one, honest!)
1973 GTV 2000 - Rowdy (or this one I hope)
|
06-10-2007, 06:53 PM
|
|
Alfa Poor in KY
|
|
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 3,807
|
|
Now the million dollar question is what about an automatic spider? This I do no know.
Best Regards,
John M
__________________
1978 AR Spider Veloce 2000.....the first and still here
1984 AR Spider Veloce............the second & gone to the parts bin
1992 AR Spider Veloce............the third and still here
1991 AR 164L........................traded on the SS
1965 AR Sprint Speciale..........in boxes.
|
06-10-2007, 07:12 PM
|
 |
Registered User
|
|
Join Date: Jun 2003
Location: Wisconsin
Posts: 372
|
|
|
speed vs rpm
Let's not forget tire size in these computations.
__________________
Paul
76 Spider
71 Spider & many parts
67 BSA
|
06-10-2007, 08:35 PM
|
|
Registered User
|
|
Join Date: Aug 2005
Location: Camlachie Ontario Canada
Posts: 1,120
|
|
|
The Alfa Romeo publication (1986) linear charting graph for all 5 gears, for the USA version of the Gad, Veloce and Quad are for stock tires.
Of course if you are non stock you need to factor in the differences in tire diameter.
Hey John M on an automatic, the tach calibration would be optional, don't you think? If not you would need to calibrate it every time you changed AT fluid....
TTFN Elio
|
06-13-2007, 12:09 PM
|
|
Registered User
|
|
Join Date: Dec 2006
Posts: 2
|
|
|
Just putting your guys words into a graphical form (as my girlfriend calls me an "enginerd").
|
06-13-2007, 12:23 PM
|
|
Registered User
|
|
Join Date: Aug 2005
Location: Camlachie Ontario Canada
Posts: 1,120
|
|
|
This graphic plot is in the Alfa Spider Spec's for the model 115 (USA version) as mentioned in my reference in earlier post.
Nice Y=mX + b fellow enginerd.
TTFN Elio
Last edited by Elio Comello; 06-13-2007 at 12:24 PM.
Reason: spelling
|
06-14-2007, 11:28 AM
|
 |
Registered User
|
|
Join Date: Jan 2005
Location: Rhode Island
Posts: 369
|
|
|
The Spider automatic is a ZF 3-speed with no overdrive, so at freeway speeds it winds out noticeably higher.
__________________
[B]'91 Spider Veloce[/B]
[SIGPIC][/SIGPIC]
[I]"Twenty years from now you will be more disappointed by the things you didn't do than by the things you did do." [/I] - Mark Twain
|
| Thread Tools |
|
|
| Display Modes |
 Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
|
'84 manufacture ~ '85 MY Spider Graduate 
