Any chance I can crowbar these on to an 87 951??

2001f4s · 01-20-2011, 06:54 AM

Sorry to be lazy here. But hoping someone can help me.

Any chance these would fit without looking to "rice racer like"

19x8.5 et54mm offset front and 2 19x11 et62mm offset rears, 5x130 bolt pattern

phoenix_iii · 01-20-2011, 07:33 AM

18''s aren't even recommended, let alone 19''... why so much wheel?

2001f4s · 01-20-2011, 07:35 AM

seemed like a good deal, but if they don't fit....

phoenix_iii · 01-20-2011, 08:50 AM

Bad deal for your suspension/bearings/everything. =) Stick with 16s, 17s, or 18s if you must (but need to make suspension changes accordingly, see the Porsche document that is in various threads)

2001f4s · 01-20-2011, 09:02 AM

Thanks Phoenix, appreciate the insight

2001f4s · 01-24-2011, 08:30 PM

Continuing to lean on you guys for input on the wheels sizes here.

Any thoughts on how well these would fit my 87 951:

7.5J x 18--ET 50
Part No: 993-362-120-03

10J x 18--ET 40
Part No: 993-362-134-06

2001f4s · 01-25-2011, 08:54 AM

TTT

Any help with the last inquiry would be great.

Thanks

Techno Duck · Techno Duck's Garage

The rears will probably not fit right. The 40 offset is really low (causing the wheel to stick out too far) and will more than likely rub on every bump you hit and on heavy acceleration with the rear end squat. Tire brand and width has a big factor in this, but the wheel to begin with is just not the ideal fitment.

The fronts will fit.

Generally speaking for a late offset car, you want in the mid 50mm offset range for the front assuming a ~8-9" front wheel and around a 60-65mm offset in the rear assuming a 9.5-10.5" wheel. This is obviously+/- a few MM both ways, but i can tell you from experience 40 in the rear is way to low.

From experience, i have run a 17x9.5 rear with a 46 or 47 offset (i forget exactly) and it rubbed very badly with a 275 width rear tire on bumps and even medium acceleration. The 18x10 you posted will be even worse.

derekc23 · derekc23's Garage

The 40 rear would work best on an early offset car like my '86. Techno Duck really did a nice job of summarizing what you'll need for your '87.

2001f4s · 01-25-2011, 07:37 PM

Techno Duck,
Thank you much. That is just the information I was after.

Much appreciated.
Scott

2001f4s · 01-31-2011, 12:38 PM

Still searching for some wheels that will fit my '87 951.

Another question on the rear wheel. Looking at a set of 18" diameter wheels where the rear states the following:
9Jx18-Et 52 "B" and 10Jx18-Et 65 "A"

So I know from what I have learned here that the 65 offset should work well in the rear, but I am not sure how one wheel can have two different offsets. Is this based on the tire width.

The fronts are: 7.5Jx18-Et50

Any help would be great.

Techno Duck · Techno Duck's Garage

So the two rear wheels are different widths?

The offset is dependent on the width of the wheel. Take a hypothetical situation involving a 9" and 10" wheel with the same offset of 55mm. Say the outside of the 9" wheel sits 1" away from the inside of the fender lip. Now the 10" wheel will sit approximate .5" farther out on both sides of the wheel, effectively cutting down the amount of clearance between the wheel and fender lip (body of car) by .5" on both sides of the wheel. There is a sweet spot of where you want the centerline of the wheel to be in order to maintain maximum clearance on both sides of the wheel well..most times you can continue to push the wheel inward as there is plenty of space in the wheel well. So by raising the offset of the 10" wheel to say 65mm you are now bringing the wheel back in by approximately .4" (or 10mm) . So effectively the wheel now sits .1" (give or take) closer to the outter fender lip, and .9" farther inwards. The limit of this on a late offset car is a 11-11.5" wheel. As you basically have no space inside the wheel well anymore. The widest i have seen on a car with stock bodywork was an 11", and yes this required pretty much a spot on offset.

I run a set of 17x10.5" wheels on my car and while i dont remember the exact offset, its 65mm or 67 if i remember right.

2001f4s · 01-31-2011, 08:48 PM

Techno Duck,

First off thank you for the patience and the explanation.
I do apprecaite it.

According to the seller each of the rear wheels have both of these two markings:
9Jx18-Et 52 "B" and 10Jx18-Et 65 "A"

That is where I am confused.
It might be that the seller is confused as well.

Quote:

Originally Posted by Techno Duck

So the two rear wheels are different widths?

The offset is dependent on the width of the wheel. Take a hypothetical situation involving a 9" and 10" wheel with the same offset of 55mm. Say the outside of the 9" wheel sits 1" away from the inside of the fender lip. Now the 10" wheel will sit approximate .5" farther out on both sides of the wheel, effectively cutting down the amount of clearance between the wheel and fender lip (body of car) by .5" on both sides of the wheel. There is a sweet spot of where you want the centerline of the wheel to be in order to maintain maximum clearance on both sides of the wheel well..most times you can continue to push the wheel inward as there is plenty of space in the wheel well. So by raising the offset of the 10" wheel to say 65mm you are now bringing the wheel back in by approximately .4" (or 10mm) . So effectively the wheel now sits .1" (give or take) closer to the outter fender lip, and .9" farther inwards. The limit of this on a late offset car is a 11-11.5" wheel. As you basically have no space inside the wheel well anymore. The widest i have seen on a car with stock bodywork was an 11", and yes this required pretty much a spot on offset.

I run a set of 17x10.5" wheels on my car and while i dont remember the exact offset, its 65mm or 67 if i remember right.