Power Brakes installed on the 33

[hdnik]

I wanted power brakes for the 33. This weekend it became reality. Thanks Jeff!

He created a kit for the car. Here are the installation steps.

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I Removed the 6 studs used to hold the Wilwood Brake Master Cylinders as they will not be required.17916

Next, installed the new brake pedal supplied in the Kit as per the Wilwood instructions using the hardware supplied in the Factory Five Brake Pedal Package as needed. Also install the brake light switch as described in those instructions.17917

Used a Grade 8 - ½ bolt of the correct length as a pivot rod as bushing is too tight for the Wilwood rod and c-clips. Used some spacers and a copper thrust bearing (From F5 Kit) so that the nut and bolt can be tightened without restricting free movement of the pedal.

Next, installed the brake pedal pad from the Factory Five Kit using its’ supplied hardware. Finally, installed the entire pedal box assembly. Now lots of room for electronics.1791817919

Only 3 of the 4 holes go all the way through; the 2 top holes and the bottom left hole (the one closest to the center of the car). Only these 3 holes will be drilled completely through the firewall and the frame members. The 4th hole (bottom right or outboard hole) will only go through the firewall and the outer side of the firewall frame member. This is because the chassis ID or Serial Number is engraved on the inside of that frame member right where that hole would come through and you I did not want to disfigure that identification stamping.1792017921

Used a 1/4” bit to open the 4th and final mounting hole up in order to tap it with a 5/16” – 18 tap.


Next, used the mounting template as a guide, and a 7/8” hole saw and a Dremel tool to open the center oval slot. You are able to see the brake lever through that slot when done.17922

Used 3M synthetic double sided tape normally used for attaching emblems to cars. It is weather proof, very sticky and fairly dense.17923

[michael everson]

Looks great. I do have a concern though That brake pedal seems to have a very high ratio. probably 10:1? I think the brakes will be very touchy. Any thoughts on this?
Mike

[hdnik]

Hi Michael,

I have to defer to Jeff on this. His design had been tested and revised along the way and he reports all well and good. Memory suggests 2 or 3 other 33's he's done already and numerous MK's which this package had evolved from. I guess we're gonna find out but i have nothing but faith in this guy.
I'm extremely pleased at how easy it all went together. If it works as good as all that, I'll be thrilled.

Now im ready to finish my brake lines.
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[Olli]

I think that it's great that Whitby (Nick, I assume when you say "Jeff" that you meant Whitby's Jeff Collins ?) has come up with a power brake kit for the '33. Nice job detailing the install Nick. I have the Whitby power brake kit in my Mark IV and from looking at your pictures the master cylinder is not the same. Perhaps the masters are the same functionally, i.e. bore size. What I like about the one that the Whitby '33 kit has is that there is no remote reservoir. That is fantastic.

Olli

[Olli]

I just looked for this brake kit on Whitby's site and couldn't find it. What is the kits part number Nick? And what was the cost?

Olli

[hdnik]

The kit is not up on his site yet, in fact this is the first one he's shipped... I guess I'm kind of the test dummy on this, though he has installed it on a couple cars he had recently built for others.

I was sworn to secrecy until he had done his revisions and he was sure he could reproduce the parts that were being made. The pedal is a new addition as he was concerned about weakening the stock cast wilwood pedal after drilling a hole for the push rod pivot... Especially older kits that already had pedals snapping.... So this one is powder coated plate. He also had to make a pad that would accept the F5 pedal pads.

The first units he installed used remote reservoirs, but he found this master would work an i agreed it would be nice not to have the extra hoses. Heres a pic of one he did with remotes.
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I will find out the bore size and see if i can find a prettier one to use, but this certainly cleans things up.... Also i will investigate a proportioning valve to use.

[hdnik]

As for cost, I really cannot say. He and i had an open account from the other parts i had purchased and a few changes were made and we have yet to reconcile my balance. I hate to speculate on the final cost, but i imagine it would be inline with the Kit he has for the MK.. . Which i think is about $400 now... You'd have to inquire, but i think he will sell a lot if thats the case.

Also i said "Jeff" because i wasn't sure if i was allowed to post his company, i think Whitby motorcar is a sponsor of the site so it should be fine i suppose... Don't want any heat from the moderator. That said... If you' never dealt with him before i can say you will not find a nicer cat than him. Just super! In fact every supplier I've dealt with on this thing has been wonderful, Mike, Tim, Jeff, Dan, Al... Jeff fits right in!!

[hdnik]

I think that it's great that Whitby (Nick, I assume when you say "Jeff" that you meant Whitby's Jeff Collins ?) has come up with a power brake kit for the '33. Nice job detailing the install Nick....

Olli

In fact there were no real instructions with the kit, just some note Jeff made on the drilling template. I sent him pics and notes on the installation when i was done... Maybe they will show up in his future kits instruction sheet.

Point is if I could do this... Anyone can.

[Olli]

Yes, Whitby's is a site sponsor.

Olli

[4wheelspin]

It looks great. Power brakes is something I started to work on last week.
I believe the issue will be when using a modular motor. I dont think it will clear the valve cover.

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[hdnik]

I agree, doesnt look like there is much room left with that engine.

I wanted to make sure the hood and side panels will clear. Using some masking tape and a few paint stir sticks i mocked things up. Rough measurements suggest that the grill sits slightly more than 7" above the top mounting hole in the grill bracket and the inside of the panels are about 1/2" oustside the radius of the firewall. Looks like at a minimum, there should be about 5/8" clearance, likely more... So should be good to go.
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[maczter]

Well, as soon as the kit is real, please let us know. I am interested, even though I have already invested in CNC reservoirs and braided lines and fittings. Please let us know asap as to when it might be ready and the cost. I will need this before my Boyd's tank!

[hdnik]

Maczter, may i suggest sending a line to Jeff Collins. info@whitbymotorsports.com

Given you have invested in remote reservoirs, why not ask about the set up shown in post number 6.

[hdnik]

Added a chrome cover and proportioning valve. Used an off the shelf stainless bracket and mounted it to one on the booster bracket bolts. Need to get some nicer 5/16 hardware next week... Galv nuts and bolts are temps. Finished the brake lines too.
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[TxMike64]

Digging up an old thread here... But did you find the travel and bore correct?

[Svtfreak]

Digging up an old thread here... But did you find the travel and bore correct?

Check out my build thread (as well as tim whittingtons) for another option on power brakes.

[DaveS53]

Getting the correct combination of pedal ratio, booster diameter and MC bore size can be tricky and it varies with the type of brakes being used. Manual brake pedals will have a pedal ratio in the 5-7/1 range, while power brakes may only be 4/1. Whether a proportioning valve is needed also depends on the brakes being used. I have Wilwood 6 piston brakes in front and 4 piston in the rear, with 12.2" rotors. No proportioning valve is needed to keep the rear brakes from locking up.

I had fun trying to get the right combination of booster and MC with a 4/1 pedal ratio. My roller came with a 7" single diaphragm booster and 1" MC. It braked OK, but took more force than any new car would. A change to a 7" dual diaphragm adds about 27% more pressure, but even that was a little wimpy. The third try went a little too far, with an 8" dual diaphragm booster and 7/8" MC. I've finally settled on the 8" dual diaphragm with 1" MC.

The bottom line is that your first setup may not be ideal.

[TxMike64]

Check out my build thread (as well as tim whittingtons) for another option on power brakes.

Yeah, I've been following your build and have seen the discussion about the electric power brake system. I think it's an interesting idea, and while I like that it all goes under the dash, I think it's somewhat complex. I like the KISS method and think the vacuum style booster is simple and proven. Plus, if I'm not mistaken, much cheaper. If the effort/force is correct, and (the big if) IF it clears the 4.6v 4V valve covers, the Whitby Kit is probably the direction I'll head.

I'm still bummed there's no hydraulic power steering option. Then I'd use a Mustang hydroboost power brake setup.

[Svtfreak]

I'm still bummed there's no hydraulic power steering option. Then I'd use a Mustang hydroboost power brake setup.

The abs system is no more complex than hydraboost. In fact, it is hydraboost. It just uses and electric pump instead of a belt driven pump to provide the pressure. It's no more complex and the failure mode is the same as hydraboost.