vsclider

Howdy,

I'm about to pick up a 1986 951 and have been researching wheel and tire size. I want to go with a 17"x7.5" wheel running a 245/40R17 Michelin Pilot Sport 4s tires. What offset would work? The car currently has early 2000's boxter wheels. and stock the offset is aprox 23.3mm I think. I don't really want to roll the fenders but I will if I have to. Thanks for the help.

MAGK944

Your car takes wheels in the early (~23.3) offset, anything higher, like the Boxster wheels that are on it, require spacers. So if you don’t want to fit spacers stick to early offset wheels.

Fwiw factory recommends the following 17in tires sizes for our cars: f 225/45/17; r 255/40/17. They also recommend fitting 968 castor blocks when going to 17in wheels, it’s a good upgrade anyway.

joseph mitro

if the suspension is still stock, then stock wheel size/ offset is 16x7F/8R and 23mm F/R.
Most all Porsches from the late 80s onward had higher offsets so those wheels won't work without big spacers as MAGK944 pointed out.

vsclider

Thanks for the help guys. I'm probably going to go with some coil overs, and measure for some custom wheels. I'll post details as well as my measurements when this all comes together.

GPA951s

FWIW (I have late offset) but im running 255/17's up front and 275 17's on the rear, and the car is lowered and never had to roll fenders..

vsclider

That looks sweet GPA951s Thanks for the information.

MC Luc

I can't believe the completely limited wheel options we have, really frustrating. Have never encountered this with other enthusiast cars. Surprised a wheel manufacturer hasn't stepped into the breach. Must be an issue of volume.

joseph mitro

Why do you think wheel options are limited? There is a huge Porsche aftermarket. I think most manufacturers are geared to larger wheel diameters - 18-21” but there’s still options for smaller. At Least if you’re open to used wheels.
OTOH Porsche’s 5x130 bolt pattern is unique so you’d need a large market to make lots of options in smaller diameter wheels

jimbo1111

Check the Porsche section at wheelenhancements.com

MC Luc

Joseph: I have been looking for 17" wheels and can really find a very limited selection, and can find some 18" wheels but they are all later model Porsches!! Vey few of which I am crazy about. Having a 1986 23et offset doesn't help, either

Jimbo1111: thanks for the tip I will check out wheelenhancements.com. Thanks!

superloaf

No one else uses 5x130 bolt center diameter so we are very limited on wheel selection. I mean, sure there are a lot if you don't mind spending $800 per wheel but I like to keep my wheel cost lower than rest of my car cost. And 17's are great for 951's! I've used 245/40's for years as Michelin stopped making our rear size back with the PS2 (yuck!) Even Singer was still suppling PS2's on their cars last time I checked which admittedly was back when all the Singer press was bubbling. And when Super Sports and now 4S's are leagues ahead of PS2's, there is no morally righteous reason for running the older tire. Plus, they aren't very good especially on wear.
Anyway, the 245/40 fitment is a little smaller and can be noticeable if you know what you're looking for. The traction deficit is not noticeable when running 225/45 fronts mostly because the Super Sports or 4S's are leagues ahead of their previous tires! But still, that extra 10mm would be nice and it does look much better, both in width and aspect ratio, on the car. Also, the speedo readings will be off with the smaller diameter 245/40. But on the plus side, the gearing will be better for acceleration although you may just end up spinning them easier now.....Life is all trade offs, isn't it?

If you end up with 245/40's all around, post some pics. I've thought about trying that although recently I've also thought about trying 245/45-17's.

odurandina

i'm amazed i used to run these 15" wheels (you can still buy today)
https://www.europeanoempartsdirect.c...4aAqUzEALw_wcB
w/ 225 60 15s 30 years ago on my 944S thinking they were (badass).
*Please suffer my embarrassment. :

Couldn't even dream about running wheel tire combo's like you all/we have now
959 17" Cup Wheels were wheels reserved for millionaires, like my GF's dad,
renown Boston developer, Bill McCabe (RIP).

MichelleJD

Took me over two years to find original Speedline for Porsche in 23et offset. Yeah, it's a pain.

superloaf

Hey, don't knock the phone dials, they're still great on VW A1 & A2's! I still wish Porsche had made a 17" phone dial wheel.

Now enjoy my gratuitous pics of my 16v Scirocco with Porsche 16" phone dials:

odurandina

the 2nd pic from the bottom looks quite Audi/VW/944/Porschey.....
like an early 80's TVR mated with a 70's Jensen Interceptor