DarrenD

So I have abandoned trying to use 16 x 11 wheels in favour of using newer 996 Turbo wheels 18 x 11 due to the lack of tire options in 16". I already own a set of wheel spacers that are 25mm and in doing all the measurements yesterday I know I can make them fit. Plus my brother has a 996 C4S so I can use his wheels to test fit.

What I don't know is how long I need for the studs. The spacers are 25mm(1") but how much longer do I need so that they'll safely protrude through the 996 Turbo wheels, anybody have any idea?

They come in various lengths up to 100mm but those seem way too long. I found a set locally that are 56mm long but that seems short to me.

951Saga

I'm using an early 21mm OE spacer with 66mm studs which are 21mm longer than the original 45mm studs. So measure the original stud from the seat to the tip and add your 25mm spacer length to keep the original ratio. Paragon sells the studs I have...

Just Measured about 9mm from wheel hub surface through stud hole to lug nut seat on 993T, 996T and Club Sport wheels.

DarrenD

Thanks, that's pretty much exactly what I needed.

It should be the orig. + the spacer right?

So 45mm + 25mm = 70mm

Thanks for the Paragon link.

FrenchToast

I wouldn't run late offset wheels on an early offset car. Which that would be, according to your other thread.

IMO, too much stress on the hub.

Find some proper offset wheels. That's me.

Take care!

DarrenD

Please explain?

I always thought stress on the hubs was created by doing what the lowriders do, hanging the wheels off the hub by running positive offset wheels. By running late offset wheels with a 25mm spacer, the load on the hub is almost directly in the centre of the wheel. I would think a 40 offset is better(achieved with a 25mm spacer on a 65 offset wheel) than the stock 23.

How would that create an issue?

On a side note: Didn't Porsche run 3" wide spacers on the old 930's? See that for me would create some stress on the hub, especially with 300-400hp.

veleno

Why not just get 25mm adapters that have the studs built in? That way you don't have to change out the oem studs.

Van

What year is your car? The early cars already have 66mm in the rear and 45mm in the front. The later cars have 45mm all around.

DarrenD

My car has an 86 turbo alum. rear suspension.

I had orig. used wheel adapters so I had to trim my existing studs.

Eric_Oz_S2

I didn't think 11" rears fitted on a 944 without body modifications?

DarrenD

I'm going to test fit this week.

odurandina

safety last.

FrenchToast

The load bearing point of wheel hub is further out, thus creating a longer lever arm. Any spacer obviously does this.

Adapters (spacers with extra lug studs/nuts) are too big for me. I would not run adapters on any car, but that's me. Another set of lugnuts to check and potentially have problems with.

Most club racing organizations have banned the use of adapters in races and even just regular events.

Many Porsches have come with spacers, (928, 911, 944.....) but never with adapters.

And also with extended studs you need to make sure the with the closed lugnuts that it seats fully against the wheel.

The lowrider effect would actually be negative offset.

Maybe I shouldn't be saying anything, I'm not an engineer by any means, but do have general knowledge.

If you want answers regarding the safety of your car I would advise anyone to not ask a forum. A car forum user is not synonomous with 'expert', including myself.

Take care,

DarrenD

So after all the frustration with this I have decided to....


Run my cookie cutters with the R888's. :-(

I am going to save my pennies for a set of CCW's, Fikse's or Kodiak's and do it up right. Lightweight 18" wheels with the proper offset and tire sizes. When I order them I will take into consideration future Porsche purchases such as an 87-89 911.

Thanks for everybody's input, it is greatly appreciated.

Van

Good plan. You'll be faster with the smaller diameter and less rotating mass.

azbanks

You've got to roll the fender lips and possibly create a little clearance on the inside fender well.