When I applied to put a 179 in FB ute, Vehicle Standards SA only requirement was that I fit self energising, or as GMH called them, duo-servo 1 3/4” front brakes, such as EJ EH. I went ahead and installed the entire HR front end with solid discs, and never looked further into fitting the EJ brakes. Until now.
Ardiesse had mentioned that he was thinking of bolting up HD kingpin front assemblies to early upper and lower control arms. The HD HR front brakes are 2 1/4”, so 1/2” wider than FB EH, which is the reason behind changing the wheel centre design at HD.
Later on I was told that the EJ EH brakes would bolt up to FB stub-axles, making the conversion relatively easy. Now I am wondering if the HD kingpin backing plates will bolt up to FB EK stubs. There are distinct part numbers for left and right FB EK and EJ EH HD kingpin steering knuckles. So it seems feasible to assume that if EJ EH front brakes will bolt up to FB EK steering knuckles. Result is self energising front brakes with an extra 20% braking surface over stock.
FB ute fixer upper, EK van on rotisserie
Last edited by Errol62 on Thu Oct 31, 2024 8:34 pm, edited 1 time in total.
getting my FB ute on the road
EK van on rotisserie
As an aside, I have a hr balljoint front end, with drum brakes, which I am going to swap to disc stubs. So the front drum brakes are sort of surplus. My friend has a sporty FB wagon, and we got all excited that the hr brakes were going to bolt up to it. Friend is now in search of HD front assemblies. In a way I’m glad because I can use a lot of the parts to put together a set of 2 3/4” rear brakes as per HD HR commercial.
Unfortunately the 2 3/4” drums are not available new after market, which could be a limiting factor to this upgrade.
FB ute fixer upper, EK van on rotisserie
getting my FB ute on the road
EK van on rotisserie
Some info below on the steering arms, from my post on putting the Mitsi vented disks onto the kingpin front end: viewtopic.php?p=229694&hilit=db005#p229694
Excerpt below:
Early Holden steering arms.jpg (464.85 KiB) Viewed 332 times
Cheers,
Harv
327 Chev EK wagon, original EK ute for Number 1 Daughter, an FB sedan meth monster project and a BB/MD grey motored FED.
An editorial change first: HD/HR front drum brakes have 2-1/4" width linings, EJ-EH are the same width as FB/EK at 1-3/4", although EJ/EH brakes are duo-servo and FB/EK brakes are semi-huck.
I have an HD front drum brake, with backing plate, stub axle and upright. So I can check the interchangeability of parts. From memory, FB/EK stub axles have two through holes - the lower ones, and two threaded holes - the upper ones. EJ-EH and probably HD king-pin stub axles have four through holes. Ken McLean alerted me to this after I found a "rogue" king-pin and upright assembly with all through holes on the stub-axle. I thought it might have been early FE, but Ken said it was most likely EJ/EH.
You'll need to replace the FB/EK steering arms with EJ-HD steering arms, and then there are a couple of ways forward: bolt the HD front backing plates onto FB/EK stub axles, using two shorter 3/8" UNF bolts at the top to go into the threaded holes in the stub-axle, or . . .
use EJ/EH uprights and stub axles on the FB/EK front suspension, and bolt the HD front brakes to the EJ/EH stub axles.
Steering chuckles are common across EJ HD kingpin, so should work.
I will let Gary know to get the steering arms along with backing plates. I need mine to use with the disc stub axles.
Sent from my iPhone using Tapatalk
getting my FB ute on the road
EK van on rotisserie
Hi Clay you can use the HD/HR Drum Brake stub axles to fit disc brakes you just need to modify them a bit and bolt on adapter plates I have a pair here that I had on Frank before I went to drop spindles, they take VN/VP front discs and calipers and can be modified again to take VT twin piston calipers as I have done.
Not sure if I'm going to use the modified Stub axles or use drops spindles once again for "The Reverend"
Member of WA FB/EK Car Club
Frankenstein EK V6 Ute
The Reverend FB Station Wagon Project
1950's Commer Light Truck (2.5 Ton)
I’m going to run the tried and true stock HR discs thanks Neil. I’ve got all the hardware, even the backing plates. Even got nos caliper kits and bearing kits. These drum spindles are surplus if anyone wants them.
FB ute fixer upper, EK van on rotisserie
getting my FB ute on the road
EK van on rotisserie
You wrote, "I can’t quite get my head around the need to use the later steering arms, considering the backing plates fit the original stubs."
Yes, they do, but -
In FE-EK brakes, the braking effort from the primary shoe is taken by the big anchor bolt at the 6 o'clock position, and then transferred to the stub axle via the steering arm, because the anchor bolt goes through the steering arm. The components are dimensioned so that the anchor bolt is as short as possible, which means that the steering arm sticks into the brake assembly quite a way, almost to the plane of the brake shoe webbing.
In EJ-HD king-pin brakes, the anchor is now moved to the 12 o'clock position, above the slave cylinder. The bottom of the brake shoes, where the adjuster now is, is free to move. This feature allows the braking force generated by the leading shoe to be transferred to the trailing shoe, increasing the self-servo action. In these brakes, the braking effort is transferred from the anchor pin to the stub axle via the backing plate. This is why EJ-onward backing plates are so much beefier than in FX-EK. And the change in brake geometry necessitated a redesign of the steering arms: no need for the anchor bolt hole in the steering arm, but also, because of their shape, FE-EK steering arms will foul EJ-onward adjusters and backing plates.
Going on what they specified for the 179 Frank yes. Quite pragmatic I thought, seeing the front brakes do most of the work. They might be a tad more liable to lock the fronts up first I suppose. An EH rear axle wouldn’t be a bad thing but it is extra work.
FB ute fixer upper, EK van on rotisserie
getting my FB ute on the road
EK van on rotisserie
