I'm upgrading my tb from stock to a 74mm tb. A trusted friend in our xf clan gave me part #a1121410125. So I ordered one off eBay and came in today and I search thru the xf forums to find the part #a1131410125 being recommended for the upgrade. Is there a difference between these two parts? And since we are on the subject I'm assuming I need to get an oring for the 74mm tb and maf housing? I don't usually work on upgrades to engines much other than k&n filters so Im just needing to know what I need to do in order to do this correctly and professionally. Thank you in advance for your input

 

You want the 113, not the 112 :
And yes, you need a Viton O ring.

Genuine Mercedes Benz Throttle Body O Ring Gasket 305 997 03 45 | eBay

 

It is my understanding that the SRT comes with TB #113 141 01 25 (74mm).
The NA comes with TB #112 141 01 25 (68mm) . . . I think your trusted friend gave you the part number for the same 68mm throttle body that you already have!

This is the 68mm that is OEM on the NA Crossfire


This is the one you want (74mm OEM on the SRT6)



You will find this to be helpful

https://www.crossfireforum.org/forum...tml#post575210

Here is the least expensive source I found for the throttle body O-ring delivered right to your door . . .

http://www.ebay.com/itm/MERCEDES-BENZ-3059970345-GENUINE-OEM-ACTUATOR-SEAL-/321627850768?pt=Motors_Car_Truck_Parts_Accessories&hash=item4ae2838810&vxp=mtr
Good Luck . . .

 

You are up pretty early and moving fast this morning George! While I was preparing my post and pulling photos, you already posted the answers!