Talking about replacing the P453 brake shoes on my TEKTRO R340 (actually R540) with Shimano R55C4.
I replaced the brake shoes of the TEKTRO R340 (actually R540 when I took them off and looked at the back side) caliper brakes on my Giant Defy 2012 with Shimano R55C4 to increase the braking power.
Apparently, the R55C4 is also the standard specification for DURA-ACE, ULTEGRA, and 105 as well as the R55 if you check the Brake (Caliper Brake) (pages 143~145) in the PDF file of the 2019-2020 Product Specifications (as of 11/13/2019) on the Shimano archive page below It looks like the C4.
The original brake shoes that came with the car were Tektro P453. It is not a cartridge type. It is not sold in Amazon now.
After installing the Shimano R55C4, the brake shoe clearance was also adjusted with the centering adjustment screw and cable adjustment bolt.
I worked with this BR-R451 instruction manual and TEKTRO TECHNICAL SERVICE INSTRUCTION Dual Pivot Caliper Brak as a reference.
When you actually ride the bike, you can feel that the brake lever is stiffer when you hold it, and that the brakes work clearly with a “sizzle! You can feel that the brakes are clearly more effective. The brakes work even at high speeds, which gives you a greater sense of security.