Install Guide for Supplemental Braking System for Fiat 500
Updated 10/15/2025 | Published 10/12/2025
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Question:
Im looking to install this system on a 2018 fiat 500 pop. Not much room to install parts and pieces under the hood. Drilling a hole in the firewall and accessing it with the cable from the engine side concerns me. What is the minimum bend radius? Does install require tapping the brake boost vacuum line? Accessing the vacuum line seems almost impossible yet alone finding it. Removing the battery may solve most of the access problems. I really like the cable system setup and how it works. Also the wireless remote monitor. Any ideas or information would be helpful. Thanks for your time John
asked by: John H
Expert Reply:
Hey John, we had a chance to install the Demco Stay In Play Duo part # SM99251 on a very similar Fiat 500 to yours that I attached an install video for down below that would walk you through the entire process. The DUO is by far our favorite braking system because of how well it works, how easy it is to install, and how reliable it is.
This would be actually what I would recommend for your Fiat and it has the best install resources we can provide since we've installed it before. Otherwise I would recommend using this as overall guide for the # RVI94FR as well since most of the components are the same, a hole in the firewall needs to be used, and there are components under the hood that need to be installed as well.
Product Page this Question was Asked From
Curt RVibrake Shadow 2 Flat Tow Brake System - Wireless Monitor - Proportional - Fixed
- Flat Tow Brake System
- Brake Systems
- Proportional System
- One-Time Setup
- Vehicle Battery
- Fixed System
- Air Brakes
- Air Over Hydraulic Brakes
- Hydraulic Brakes
- Wireless Display
- CURT
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John H.
10/15/2025
Jameson, I think the Kurt would make for a cleaner install if space can be found under the fiat 500 hood. I would also consider The Curt RVi Series 4 Portable Flat Tow Brake System. It appears straight forward and a simple setup. Any feedback from your end on reliability and function. My only concern is movement from not being fixed. I would assume the bullseye monitor would indicate any problems due to the unit shifting around during travel. Thanks for your time. John