1981 911SC Speedometer question

germaniac · 02-19-2008, 06:03 PM

Hey guys,

I recently became aware of the fact that (supposedly) my SC wasn't made with the VDO 160 MPH gauge that it has in it...is this so? I do not have any indication in the paperwork I got from the previous owner of this being the case. Also, for the last 5 years or so, there is no paperwork with mileage on it...is there anyway for me to verify that my odometer is correct?

If this isn't the original speedo, how do I determine if it needs calibration?

Thanks for all the help and tolerance of my questions...

Rob

aigel · aigel's Garage

All cars sold in the US in 81 had 85 mph speedometers. This includes Porsches.

George

tcar · 02-19-2008, 07:05 PM

Federal law.

It's not original... unless, perhaps it's a gray market import that didn't get it changed.

Never seen one w/ paperwork. Never seen one (recently) w/ an 85 mph speedo.

germaniac · 02-19-2008, 07:08 PM

No, I meant any paperwork that may have detailed the work done switching out a speedo.

tcar · 02-19-2008, 07:34 PM

Quote:

Originally Posted by germaniac

No, I meant any paperwork that may have detailed the work done switching out a speedo.

Yeah, sorry, that's what I meant. Speedo paperwork... never seen any...

mike635 · mike635's Garage

My '81SC has the higher limit speedo too. The car has 140K miles and I purchased it from my brother who put about 50K of those miles on the car so I wonder if it's the original speedometer? (he didn't replace it) I would think that if it were replaced by some previous owner the car might have a lower mileage reading although I would imagine you can take a new one and spin it up so it wasn't starting from zero. Of course it's possible that the chassis really has 240K miles on it...

mike

javadog · 02-20-2008, 04:33 AM

Rob,

A shop that replaces a speedometer is supposed to do one of two things. Either change the new one to read the same number of miles as the old one (ususally, to do this, the speedo gets sent out to a speedometer shop like Palo Alto, or North Hollywood) or they place a sticker in the car showing the mileage at the time the switch was made. Not all shops are ethical and it's safe to say that many owners are even worse, so this often gets overlooked.

I'd look the car over carefully, to see if you have a sticker. Look inside the door jambs, in the car's service book, on the back of the speedometer, etc. If you don't find one, run a carfax and see if anything shows up with respect to mileage. Some states require annual inspections that will leave a paper trail of mileage history. You can also look through what paperwork you have for the shops that worked on the car in the past and call them to see if they have any records that you didn't get. If you are really diligent, you could search state DMV records and try to trace the ownership history of the car, then try to locate and contact the previous owners. It's a lot of work but it can be done.

Good luck,
JR

tcar · 02-20-2008, 06:03 AM

A lot of them were replaced by private owners or small indy garages... no paperwork...

petrolblue83911 · 02-20-2008, 07:27 AM

it takes about 3 minutes to change out a speedo, and you can still buy oem new vdo gauges, so if the po wanted a 160mph unit, he, like many have done, could have just boght the part and slaped it in. There is no difficulty in doing this-but as stated already, to get the new guage to read proper miles on the car it would need to be re-set

Ray B · 02-20-2008, 07:50 AM

There is a place on page 1 of the red Warranty booklet to be filled out if the speedo was replaced. Most good shops would document the switch- which is required by law. Private owners on the other hand.............

mike635 · mike635's Garage

Interesting comments, thanks. In reality, I don't care that much but always wondered if the speedo was original, sounds like it's probably not.

Ray - quite a nice collection of bikes/cars you've got! I've got an '88 BMW R100RS that I love (kind of like 1/3 of a 911?) but ever since I bought the 911, it spends a lot of time sitting in the garage in the trickle charger. Don't know if I could bring myself to sell it but if the transmission ever goes out on the 911 and I need the cash....

mike

Ray B · 02-20-2008, 12:25 PM

Thanks Mike. You're right-on cars as old as ours, the ODO has generally stopped working at some point or another anyhow. Take the car for what it is and enjoy. It will probably outlast us all. I really like the RS bikes. There are quite a few of us Porsche guys in town who ride the flat deuces! Cheers. Ray

911Freak · 02-20-2008, 12:41 PM

My Euro '81SC came with a 180mph/KM speedo, when it was brought into the US in Mid 85' the Euro 180mph/Km was removed and a 160mph/mi speedo replaced..

The shop in TX that did the work placed a label in the housing, date they did the work and calibration date... Then they recalibrated the Euro 180mph/Km speedo for what ever reason... just a little piece of mind in a gray mrkt car...

Oh, all the mileage in the orig odo, matched the 1st US registration... this would be another way you could track the vehicle mileage of your car..
I used Carfax, then contacted each states DMV for records..worked well but was time consuming..

schoward · 02-21-2008, 01:34 PM

Quote:

Originally Posted by Ray B

There is a place on page 1 of the red Warranty booklet to be filled out if the speedo was replaced. Most good shops would document the switch- which is required by law. Private owners on the other hand.............

The above is true, and as a data point, the page Ray refers to in my '81 booklet is stamped by the dealer that originally sold the car and indicates a speedo change at 398 miles (mine has a 150 mph speedo). Looks like dealers may have accomodated customer requests to ditch the 85mph speedo post-sale.

rs6er · rs6er's Garage

I swapped out the 85 MPH speedo for a 150 MPH one when I had about 19,500 miles on the original (in the early 1980s). When I tell the insurance companies that (2500 limited use mile policy), they don't care. They only want to know what the one in the car shows.