Modern Rodding TECH

InTheGarageMedia.com

1. Jason Scudellari welds reinforcements to the cowl of his Model A Ford roadster to mount a Kugel Komponents 90-degree brake and clutch pedal assembly.
Takin' a Brake
A Look at Underdash Master Cylinders and Electric Boosters
By RON CERIDONO Photography by Brian Brennan & Jason Scudellari
O

ne of the best-known names in the world of hot rodding is Kugel Komponents. Its founder, Jerry Kugel, became well known for installing independent front and rear suspensions under hot rods—that is, when he wasn’t chasing records on the Bonneville Salt Flats.

Early on Jerry worked with the legendary Ak Miller before opening his own shop, Jerry’s Garage, in 1969. Eventually, no doubt due to the combination of Jerry’s mechanical capabilities, business acumen, numerous magazine articles showcasing his abilities, and his understanding wife Judy, Kugel Komponents opened in 1977. Today Kugel Komponents is a family run business: daughter Jerilyn is the office manager, son Jeff is product manager, and son Joe is the lead fabricator.

Along with independent front and rear suspensions and other “komponents” Kugel offers some rather ingenious brake pedal systems. There are standard, through-the-firewall configurations as well a reverse-mount 90- and 180-degree configurations. The reverse mount assemblies tuck the brake master cylinder (and clutch master cylinder if used) behind the dashboard. This eliminates exhaust interference caused by under floor pedals and keeps the firewall clean as well. Reverse-mount 90-degree brake pedal assemblies are available with or without boosters and clutch master cylinders, while 180 assemblies are available with clutch master cylinders but use only manual brake master cylinders.

All Kugel Komponents pedal assemblies are made from laser-cut 10-gauge steel with 3/8-inch steel pedal arms. Pedal pivot points have Oilite bushings, bellcrank bushings use UHMW polyurethane bushings, and there are brackets for a mechanical brake light switch. It should be noted that these pedal assemblies will require some braces and/or reinforcements to be fabricated as part of the installation.

Another well-known name in the world of hot rodding is Troy Trepanier. Along with his late father, Jack, Troy opened the doors to Rad Rides By Troy in 1995. It didn’t take long for the shop to gain a reputation for being one of the best in the business. Building a string of high-profile cars, including the Goodguys Street Rod Of The Year, Ridler, and America’s Most Beautiful Roadster award winners.

Proving hot rodding runs through the veins of the Trepanier family, Troy’s son, Jack, heads up the Rad Rides Performance Parts division of the company. One of their products that caught our attention is the Tesla electric power brake system. These electric boosters have a sensor that recognizes the force applied to the brake pedal. That sensor sends a signal to the ECU (electronic control unit) that activates an electric motor driven screw assembly that helps apply pressure to the master cylinder.

Electric power brake boosters are found on a variety of electric cars, such as the Tesla as well as some conventional internal combustion–powered vehicles. The Rad Rides crew were quick to recognize all the advantages of these units, specifically no external proportioning valve needed as the master cylinder includes an internal bypass that controls front-to-rear brake pressure. Additionally, no vacuum source is required. Rad Rids Performance Parts modify these units so only three wires are required (three power and one ground) and a machined 6061 billet reservoir that is hard-coat black anodized is added. As these electric brake boosters are extremely effective, only a 4 or 4.5:1 brake pedal ratio is required. So how good are these electric boosters? Jack tells people to wear a mouthguard if they want to try a normal pedal ratio.

Recently we were able to catch the installation of a Kugel 90-degree brake pedal assembly with a Rad Rides’ electric power brake being installed in a ’32 Ford roadster. The result was a clean, simple, and extremely effective brake system, but it’s no surprise that when Kugel Komponents and Rad Rides Performance Parts gets together something special is going to happen.

Our Kugel Komponents pedal assembly came with Wilwood master cylinders for the clutch and brakes, fluid reservoirs, and optional mounting brackets.
2. Our Kugel Komponents pedal assembly came with Wilwood master cylinders for the clutch and brakes, fluid reservoirs, and optional mounting brackets.
Scudellari fashioned a firewall reinforcement from 1/8-inch steel. The Kugel pedal assembly will attach to this plate via a fabricated mounting bracket.
3. Scudellari fashioned a firewall reinforcement from 1/8-inch steel. The Kugel pedal assembly will attach to this plate via a fabricated mounting bracket.
To secure the pedal assembly to the reinforcement plate Scudellari made threaded standoffs from tubing that will be welded to a second plate.
4. To secure the pedal assembly to the reinforcement plate Scudellari made threaded standoffs from tubing that will be welded to a second plate.
The standoffs will attach to the Kugel mounting brackets with Grade 8 bolts.
5. The standoffs will attach to the Kugel mounting brackets with Grade 8 bolts.
Here a test-fit of the standoffs shows the space between the Kugel pedals and the firewall mounting bracket.
6. Here a test-fit of the standoffs shows the space between the Kugel pedals and the firewall mounting bracket.
With the threaded standoffs welded in place the second plate, which the pedal assembly will attach to, will be welded to the reinforcement on the firewall.
7. With the threaded standoffs welded in place the second plate, which the pedal assembly will attach to, will be welded to the reinforcement on the firewall.
Kugel’s master cylinder mount/pedal assembly attaches to the optional angle brackets, which in turn bolts to the mounting plate. The critical concern here is to mount the pedal assembly in proper relationship to the steering column.
8. Kugel’s master cylinder mount/pedal assembly attaches to the optional angle brackets, which in turn bolts to the mounting plate. The critical concern here is to mount the pedal assembly in proper relationship to the steering column.
The multiple vertical holes in Kugel mounting brackets provides options for positioning the master cylinders as well as the location of the pedals in relationship to the floor.
9. The multiple vertical holes in Kugel mounting brackets provides options for positioning the master cylinders as well as the location of the pedals in relationship to the floor.
Here the pedal assembly is bolted in place; the brake master cylinder will bolt to the plate with the large hole.
10. Here the pedal assembly is bolted in place; the brake master cylinder will bolt to the plate with the large hole.
The pedal assembly mounts the clutch master cylinder 180 degrees or facing to the rear from the pedals. The linkage and 90-degree bellcrank for the brake master cylinder can be seen.
11. The pedal assembly mounts the clutch master cylinder 180 degrees or facing to the rear from the pedals. The linkage and 90-degree bellcrank for the brake master cylinder can be seen.
In this application a Wilwood 1-inch bore master cylinder was used; power brake boosters are also available.
12. In this application a Wilwood 1-inch bore master cylinder was used; power brake boosters are also available.
For manual transmission applications with a hydraulically activated clutch, a 3/4-inch master cylinder is supplied.
13. For manual transmission applications with a hydraulically activated clutch, a 3/4-inch master cylinder is supplied.
Here the brake and clutch master cylinders are in place. The brake master cylinder allows the lines to be connected to either side by swapping the fittings.
14. Here the brake and clutch master cylinders are in place. The brake master cylinder allows the lines to be connected to either side by swapping the fittings.
Kugel offers two types of pedals, slots or solid; we opted for the slotted versions.
15. Kugel offers two types of pedals, slots or solid; we opted for the slotted versions.
When properly located there will be 7 to 8 inches from the pedal pad to the floorboard.
16. When properly located there will be 7 to 8 inches from the pedal pad to the floorboard.
A pair of Lokar pedal pads were the final touch to this installation.
17. A pair of Lokar pedal pads were the final touch to this installation.
Troy Trepanier’s Rad Rides Performance Parts offer this very popular Tesla electric power brake assembly. In this case it is firewall mounted.
18. Troy Trepanier’s Rad Rides Performance Parts offer this very popular Tesla electric power brake assembly. In this case it is firewall mounted.
These sophisticated power brake units with 11 to 16 V. If power is lost it will act like a manual brake system.
19. These sophisticated power brake units with 11 to 16 V. If power is lost it will act like a manual brake system.
Rad Rides Performance Parts supplies two stainless steel brake fittings for the master cylinder that accept -3 AN lines.
20. Rad Rides Performance Parts supplies two stainless steel brake fittings for the master cylinder that accept -3 AN lines.
Due to their effectiveness, electric power brake boosters require less leverage—that is less of a pedal ratio than conventional braking systems.
21. Due to their effectiveness, electric power brake boosters require less leverage—that is less of a pedal ratio than conventional braking systems.
Rad Rides Performance Parts and Kugel Komponents collaborated on creating pedal assemblies for electric brake boosters (on the right). Note the smaller bolt pattern.
22. Rad Rides Performance Parts and Kugel Komponents collaborated on creating pedal assemblies for electric brake boosters (on the right). Note the smaller bolt pattern.
Due to the difference in pedal ratio and the relative location of the booster/master cylinder assembly, modifications to the Kugel assembly bellcrank were required for the Rad Rides Performance Parts booster.
23. Due to the difference in pedal ratio and the relative location of the booster/master cylinder assembly, modifications to the Kugel assembly bellcrank were required for the Rad Rides Performance Parts booster.
Here a pedal assembly with an electric booster is in place. Standard-length brake pedals are used, the difference in pedal ratio is made up at the bellcrank.
24. Here a pedal assembly with an electric booster is in place. Standard-length brake pedals are used, the difference in pedal ratio is made up at the bellcrank.
The electric power brake master cylinder is extremely compact—the rear brake outlet is to the left (closest to the pedal), the rear brake outlet is to the right. Note the reinforcement plate on the firewall of this ’32 Ford.
25. The electric power brake master cylinder is extremely compact—the rear brake outlet is to the left (closest to the pedal), the rear brake outlet is to the right. Note the reinforcement plate on the firewall of this ’32 Ford.
The is the bellcrank on a Kugel pedal assembly for “conventional” brakes.
26. The is the bellcrank on a Kugel pedal assembly for “conventional” brakes.
For comparison this is the bellcrank for an electric booster.
27. For comparison this is the bellcrank for an electric booster.
This is a completed installation under the dash of a ’32 Ford roadster—wiring is simple enough with only three wires required. Note the brace that ties the pedal assembly to the lower dash structure.
28. This is a completed installation under the dash of a ’32 Ford roadster—wiring is simple enough with only three wires required. Note the brace that ties the pedal assembly to the lower dash structure.
SOURCES
Kugel Komponents
(562) 691-7006
kugelkomponents.com
Lokar Performance Products
(877) 469-7440
lokar.com
Rad Rides Performance Parts
(815) 468-2590
radrides.com/shop
Wilwood Engineering
(805) 388-1188
wilwood.com
Modern Rodding

VOLUME 4 • ISSUE 39 • 2023