Alignment question/computer?
07-30-2002, 01:58 AM
#1
Race Car
Thread Starter
Alignment question/computer?
Sorry if this has been posted before, but I did a search and didn't come up with a lot. I was at a tire shop today and I was looking at getting a different size tire for my '84 944. I was thinking about stepping up from 215/60/15 to 225/50/15, still debating about that, but the mechanic told me that I would have issues with not only trying to find the proper numbers for alignment with my new wheel dimensions, but it also might screw up the computer as it would read incorrect revolutions and effect my engine performance. I had never heard of such a thing and this blew my mind. Can anyone shed some light on this subject for me? Thanks again.
07-30-2002, 02:16 AM
#2
I don't agree with either of the comments. Expecially the comment about the computer being messed up, making the car run poorly. Your '84 has a cable run speedometer so the computer would never know the revolutions that the tires are making. The cable goes from the front left tire to the speedometer and thats it.
Go find a better tire shop.
HTH!
Go find a better tire shop.
HTH!
07-30-2002, 02:26 AM
#3
Race Car
Thread Starter
I agree with you, when the mechanic started talking about my computer when I was talking about tires, I gave him a look like he had two heads or something. Definitely seemed fishy. He also kept trying to push H-rated tires on me even though I made it quite clear that I needed at least a V-rating if I am going to the Glen with this thing.
07-30-2002, 08:38 AM
#4
That mec just wanted to show you he knows something about Porsche's.. 
There's nothing wrong with that setup you were planned.I used to have same setup in my previous '87 944.Since you have cable operated speedo, your computer does not know anything about the speed you are driving.
Most of us who are driving newer models with electric speedo use different tire setup than original.Atleast my computer is still running fine !
Olli
'88 951
There's nothing wrong with that setup you were planned.I used to have same setup in my previous '87 944.Since you have cable operated speedo, your computer does not know anything about the speed you are driving.
Most of us who are driving newer models with electric speedo use different tire setup than original.Atleast my computer is still running fine !
Olli
'88 951
07-30-2002, 03:34 PM
#5
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Originalsterm,
First post here! That guy has no idea what he's talking about. Why not go with 225/60/15, I run them on my 83 with cookie cutters, no problems. Does any one have specs for alignment on the size tires? I'm planning on doing it on Wednesday. <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />
First post here! That guy has no idea what he's talking about. Why not go with 225/60/15, I run them on my 83 with cookie cutters, no problems. Does any one have specs for alignment on the size tires? I'm planning on doing it on Wednesday. <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />
07-30-2002, 07:09 PM
#6
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Hey 83, what kind of tires (brand, speed rating, etc) are you running? The 60 series isn't that much bigger than a 215/60/15, but I just curious why you didn't go 225/50/15 like a lot of other guys on here? Welcome aboard, I'm pretty new here myself.
07-30-2002, 10:44 PM
#7
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More tread on the pavement, but I loose on the lower profile. ie. 215mm wide vs 225cm wide on the tread, and 50mm from side wall to tread vs. 60mm from side wall to tread. I do have to keep in mind the speedo calibration is off but not much. I decided on Dunlop SP sport 5000- 225/60/15 on cookies. Was it a good choice? Anybody else run that size? <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />