mtnman82

Been needing new tires for a while now and the 16" options just aren't there anymore so going to move up to some 17" wheels.

I thought I read somewhere on here that when going to 17" or 18" wheels, there were some mods which were recommended to the front suspension or hubs or ??? Can anyone steer me towards a thread or some info on this? Or am I good to just slap the 17" wheels/tires and go? I am planning on going with either Cup 1 or Cup 2 wheels with the Dirrezza Star Spec's if it matters...

Arominus

The factory wants you to use 968 caster blocks for 17s

mtnman82

Thanks!

mikey_audiogeek

You should look up the TSB, it's been posted here before. The key safety upgrade is the caster pins, not the caster blocks.

Dougs951S

What upgrade pin are you referring to? Does the 968 not use the same 19mm/18m caster pin as the 944?

mikey_audiogeek

The 968 pin is machined from billet versus the 944 pin which is machined from cast.
The 968 pin also has an improved clamping arrangement to prevent unintended movement.
When you put them side by side, I'm sure you'll agree that the 968 pin is an upgrade.
The last two digits of the part number indicate the version number.

https://rennlist.com/forums/924-931-...ml#post8455123

mikey_audiogeek

...however the TSB states that the main reason for using the newer caster pin is the revised caster setting for 17" wheels.

Dougs951S

Thanks, didn't know the 68' part was billet. Definitely an improvement, though of little consequence to me since I'm running steel arms.

MAGK944

Basically as stated there is an improved (billet) pin and improved (less rubber) castor block to handle the extra weight and forces when you add 17in wheels. Also because when you go 17in you normally also go wider on the tires, so to negate any "tramming" that might cause there is a new factory castor setting.

mtnman82

Thanks for the additional info guys! I'll try to find the TSB and link it in this thread. While I'd love to go wider I'm stuck with the 7" and 9" stagger on the cups, so was only going to go up to 235/45-17 f & 255/40-17 r. Guess I'm looking at the pins and blocks... Any suggestions for the best source/price?

MAGK944

Here are sections of the bulletins:

mikey_audiogeek

Great info! Just need to note that the caster pin has been revised since then so the part number now ends in 03 not 02 - keep this in mind when searching.
Cheers,
Mike