16x (8”and 9”) or (7”and 9”)?

[Redgard]

Hi
I have an early turbo. 1976. The car has a 3.3 engine ( original 3.0 case is on a shelf)with about 400hp.
It also has coil overs, upgraded sways and a front strut tower brace.
I have 16” Fuchs for it ..in both 7” , 8” and 9” widths..
I will be buying new tires soon and would like to know what the best wheel configuration would be?
I drive this car aggressively almost daily and will probably go to the track to increase my skill set and appreciation of its driving finer points..
is there a consensus on what staggered set up is best?
Thanks!
Christian / redgard

[Bill Verburg]

Originally Posted by Redgard

Hi
I have an early turbo. 1976. The car has a 3.3 engine ( original 3.0 case is on a shelf)with about 400hp.
It also has coil overs, upgraded sways and a front strut tower brace.
I have 16” Fuchs for it ..in both 7” , 8” and 9” widths..
I will be buying new tires soon and would like to know what the best wheel configuration would be?
I drive this car aggressively almost daily and will probably go to the track to increase my skill set and appreciation of its driving finer points..
is there a consensus on what staggered set up is best?
Thanks!
Christian / redgard

It depends on the tires, 245/45 on a 9 would be a good choice in back but there aren't a lot of choices for the tire, if you want one of the few that are available that/s the way to go, Otherwise 8 w/ a 225/50

in front similarly it depends on what is used in back, 8 w/225/45 or 225/50 or 7 w/ 225/45 225/50 or 205/55 or 205/45

[Redgard]

Hi thanks for the tire size recommendation.. I guess I was wondering if less width on the front might have some advantages, like better tracking etc. with 400 hp. Seems like 9” on the rear is a no brainer.

[danco_]

Go 8s up front if you can.

Are these Porsche Fuchs wheels in 16x8 for the front? Second, are the 8s 911 wheels or 951 wheels that are going on the front?


I've never heard anyone complain of too much grip from a street tire.

[Trackrash]

I remember seeing an early turbo with much wider wheels. I am guessing they removed the spacers.

FWIW, I am running 7s and 8s with 225f and 245r on my '71. Won't a turbo fit 9s and 11s minus the spacers?

[danco_]

Originally Posted by Trackrash

I remember seeing an early turbo with much wider wheels. I am guessing they removed the spacers.

FWIW, I am running 7s and 8s with 225f and 245r on my '71. Won't a turbo fit 9s and 11s minus the spacers?

You are correct. 9s Front and 11s Rear is pretty common, especially for the 73 RSR backdate cars. Super common specs.


That being said, not sure what the OP is comfortable running regarding tire sizes.

8" wheels front and 9" wheels rear is a no brainer. Personally, I'd go wider, but the wider you go, the more rotation mass you introduce into the driveline.

Pick your battles; find the right balance FOR YOU.

[Bill Verburg]

The choke points here are
1) what tires are available and that you want to use
2) what wheels you want to use, here the choice of 16" Fuchs

so follow this decision tree.



In 16 245/45 is pretty much it, you could use something like the P7 corsa in 255/50 or 315/40 but these are pretty tall tires and are energy hogs, w/ a 3.3t that is certainly doable but the 325 needs a 10.5 to 12.5 wheel so no Fuchs , the 255/50 wants a 7 - 9 so a 9x16 Fuchs is what you want.

now in front you need to balance the 255/50 rear but there are no Corsas smaller than the 255/ so now go to another tire
say BFG Sport Comp-2, 255/50 rear is available so again the Fuchs 9

in front you need to consider a matching height and width, 225/50 is too short so the only choice is 245/50 you'd want an 8 for that tire


Now consider the effect compared to a smaller but still excellent tires choice



Big thing that pops out is the net loss of torque available for acceleration of ~78lb-ft, that will hurt