Page 1 of 1

#1 S2 upright on a S1

Posted: Sun Dec 07, 2025 6:06 pm
by 40GT
Are there any differences that would make fitting S2 uprights to a S1 car difficult, ie does any geometry change, steering track contact, ball joints etc.

The reason I ask is I have quite a few Girling 18/4, 16/4 calipers along with various AR/BR and CR too, the problem is all these calipers have a 3.5 inch mounts, non have 3 inch as the S1.

Just putting the question out there so I can decide whether to just buy new S1 Zues and be done.

Cheers, Sean.

#2 Re: S2 upright on a S1

Posted: Sun Dec 07, 2025 7:30 pm
by angelw
Hello Sean,
No problem whatsoever.
Regards,
Bill

#3 Re: S2 upright on a S1

Posted: Sun Dec 07, 2025 8:17 pm
by mgcjag
If uprating the front then you need to think about the rear.
Steve

#4 Re: S2 upright on a S1

Posted: Sun Dec 07, 2025 10:21 pm
by 40GT
Thanks Bill, yes Steve the previous owner had put S2 calipers on the rear, whether these will pair with 18/4's I need to look into.

#5 Re: S2 upright on a S1

Posted: Mon Dec 08, 2025 2:27 am
by angelw
Hello Sean,
One thing I forgot to mention, is that you will probably have to change the position of the mount brackets that are spot welded to the Rotor backing panels, but that isn't a big job.

Regards.

Bill

#6 Re: S2 upright on a S1

Posted: Mon Dec 08, 2025 6:48 pm
by Series1 Stu
Would Sean need to fit flat hub wheels if he changes the uprights, discs and calipers for Series 2 parts?

Regards

#7 Re: S2 upright on a S1

Posted: Tue Dec 09, 2025 7:49 am
by chrisfell
“Would Sean need to fit flat hub wheels if he changes the uprights, discs and calipers for Series 2 parts?”

No.

My S1 has S2 uprights. No idea when they were acquired. Before my stewardship of the car.