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StopTech ST-40 Front 2-piece rotors part number

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42
26
Exp. Type
HPDE
Exp. Level
5-10 Years
Los Angeles
Hello TMO

Does anyone have part numbers for the 2-piece front rotors and hats (L&R) that came with ST-40 14” front big brake kit? I need new replacement rotors but couldn’t find the part numbers in their website. Any help would be appreciated.

Thanks 🙏
 
501
550
Exp. Type
W2W Racing
Exp. Level
20+ Years
Snowy North
Should ask Eric at Stop Tech...or Ken @ KNS.

First, tho, search up what ST identifies as min allowable and mic out your as-found thickness...toss them if you're close.
 

Mad Hatter

Gotta go Faster
5,243
4,231
Santiago, Chile
For me, the discs never get to minimum thickness... Just watch out for the heat cracks and change them when your finger nail catches on them. Or when the cracks get close to the outer edge. Looks like you have a little life left on those discs still. But good time to have those new rings handy.
 
1,249
1,243
In the V6L
Hello TMO

Does anyone have part numbers for the 2-piece front rotors and hats (L&R) that came with ST-40 14” front big brake kit? I need new replacement rotors but couldn’t find the part numbers in their website. Any help would be appreciated.

Thanks 🙏
In my experience, when it comes to Stoptech brakes, this guy, Dave Zeckhausen, at https://www.zeckhausen.com/catalog/index.php?cPath=24is is the pre-eminent "we got this" guy to talk to, and maybe buy from.

I put together two of Stoptech front setups for one of my Mustangs, a 355 set for 18" rims and a 380 set for 19's. Everything was plug and play and Dave got me the various spare parts so I could parts-bin the two sets without ending up with a bunch of extra parts. I had the calipers on Staubli's and I could swap one set to the other in about 20 minutes.
 
Last edited:

Bill Pemberton

0ld Ford Automotive Racing Terror
8,496
8,493
Exp. Type
Time Attack
Exp. Level
20+ Years
Blair, Nebraska
You can usually call the guys at Girodisc direct and often catch one of the owners. Smaller Company , similar to how Stoptech operated 15 years ago, and all done in the US.
 
42
26
Exp. Type
HPDE
Exp. Level
5-10 Years
Los Angeles
These are Baer 2-piece rotors. They are beefy/heavy and mininum thinkness is 27.76mm. I am currently at 31.2x mm so plenty left. I got girodisc 2-piece on the rear. I will hit them up and see what they have for the ST40 front calipers. I believe the rotors are same spec as fr500s. I will measure and email them. Thanks everyone.
 

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