RCR40 Handbrake?

Chet Zerlin

Supporter
Hi all,

I've reached the point in my RCR40 build where it's time to install the handbrake system. I have read some posts here indicating some disappointment with the system, that it isn't strong enough to pass a safety check, etc.

I've already drilled the two holes to snake the cables into the cockpit but before I begin the process of drilling and taping to install the bracket for the caliper I'd like to hear back from others on this forum that have installed the RCR system to make sure it's worth installing it - as opposed to considering some of the alternative I've also seen posted on this forum (like the Tesla electric caliper, the one offered by Wilwood, etc.)

Thanks in advance for your replies!

Chet
 
Hi Chet,

I have the RCR handbrake system installed on my car, and I can tell you it's not a very well-functioning system. When I first started driving my car, I discovered the calipers were dragging on the inside of the rims which left permanent score marks. I had to shave off a good bit of metal from the outboard surface of the calipers to gain clearance. Now I'm having problems with the calipers dragging on the rotors. The trouble is, backing off the pad adjusters to eliminate the dragging renders the calipers almost useless in being able to hold the rotors when applied. I've not given up on them yet, but I'm getting there.

Mike
 

Chet Zerlin

Supporter
Thanks Mike. I’ve seen similar comments in different build threads. Anyone fitted a different solution/system to their RCR40?
 

Scott

Lifetime Supporter
I wouldn't use the manual system. I can't speak for the RCR40, but lots of SL-C owners are using a Telsa e-brake and an aftermarket controller. I went with Hi-Spec which is very compact and the ECU is potted in a cast metal case. It not only weighs less in total, it has lower un-sprung weight despite electric motors being mounted to the calipers. The link below compares the size and weight of the RCR unit and the HiSpec unit.

Parking Brake P2 — Swartz Garage
 
I found the Tesla caliper very bulky, although with spacers, it can be widened for most rotor thicknesses.

With Corvette C6 rotors, you can use the drum of the rear rotor for the handbrake. Custom back plate to accommodate the standard shoes (190mm diameter), springs, adjusters and levers. Not RCR, but similar set up. You can use the C7 Corvette actuators, or old school cables.

This set up is more for aesthetic reasons.
 

Chet Zerlin

Supporter
Thanks Scott and Troy for your replies. Looking at the Tesla calipers I'm not sure it would fit since it does jut out quite a lot for the electric motor. Wondering if anyone on this site with an RCR40 has tried to install one?

Scott, that's an excellent evaluation of the Hi-Spec system - thanks for sharing it!

Chet
 

Joel K

Supporter
I’ve recently installed the RCR parking brake calipers on an SLC. They are made by IPSCO. Planning on using a heavy duty electric actuator instead of a handle to apply tension to the cables. I really like the Hispec solution, but figure I’d give these a chance since I already own them. Not sure about the differences between the GT40 and SLC versions, but one thing I noticed that with the provided mounts is that about .25” of pad was not touching the rotors so I made new brackets. Going to test them sometime over the winter. No idea if they will do the job.
 
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Chet Zerlin

Supporter
Hi Joel. Those IPSCO calipers are completely different than the calipers supplied with the RCR40 but I imagine with the correct bracket they could be fitted to my car. The question of course is are they better or just different.:) I’d be interested in hearing your experiences with them.
 

Joel K

Supporter
Hi Joel. Those IPSCO calipers are completely different than the calipers supplied with the RCR40 but I imagine with the correct bracket they could be fitted to my car. The question of course is are they better or just different.:) I’d be interested in hearing your experiences with them.

Chet, we will see. It’s hard to understand what the issue is. IPSCO has been selling these calipers for a long time. They make a kit for the Dodge Viper when you upgrade the brake package and have to remove the stock parking brake and people seemed happy with them. For some reason, seems like quite a few SLC builders gave up on them although I know a couple who used a linear actuator and got them to grab good enough. I just ordered the linear actuator and will post the result when done testing.
 

Chet Zerlin

Supporter
Hi Joel,
Attached is an image of the RCR40 handbrake system that comes with the kit. As you can see the calipers are much different than the ones sold by IPSCO. I'm hearing that one of the issues with making this system work has to do with the difficulty of adjusting it so that the pads stay far enough off of the rotor (so they don't stay in contact with it when not engaged) but making sure this adjustment doesn't result in the pads being too far away from the rotor to hold solidly when engaged. It's a very simple caliper design (maybe too simple?) where a lever when pulled moves the brake pad on one side closer toward the rotor. It's also designed to float on the bracket to return to unengaged status when the handbrake cable is released. In theory this should work fine - but it seems that in practice there are issues (maybe because the tolerances in this design are so wide?).

I also looked into installing an "in line" parking brake as an easy solution since it would use the existing rear calipers and the RCR40 brake plumbing already has the rears on a separate circuit. Still researching if this would satisfy my state's requirement that a parking brake be engaged separately from the brake system.

It may be that the RCR supplied handbrake is the best system for me to install - just trying to make sure of that before moving forward with it...

Chet
DSC_0505.jpeg
 

Kyle

Supporter
I still haven’t installed a parking brake on my car, in Florida there are very few hills. However I still want to do it for the occasional time I need one.

Let me ask, how is everyone engaging the effectiveness? For me I would say that as long as it holds the car, with it in gear from rolling down a hill, then it’s plenty effective. Are they so weak that they won’t do that?
 

Joel K

Supporter
Hi Joel,
Attached is an image of the RCR40 handbrake system that comes with the kit. As you can see the calipers are much different than the ones sold by IPSCO. I'm hearing that one of the issues with making this system work has to do with the difficulty of adjusting it so that the pads stay far enough off of the rotor (so they don't stay in contact with it when not engaged) but making sure this adjustment doesn't result in the pads being too far away from the rotor to hold solidly when engaged. It's a very simple caliper design (maybe too simple?) where a lever when pulled moves the brake pad on one side closer toward the rotor. It's also designed to float on the bracket to return to unengaged status when the handbrake cable is released. In theory this should work fine - but it seems that in practice there are issues (maybe because the tolerances in this design are so wide?).

I also looked into installing an "in line" parking brake as an easy solution since it would use the existing rear calipers and the RCR40 brake plumbing already has the rears on a separate circuit. Still researching if this would satisfy my state's requirement that a parking brake be engaged separately from the brake system.

It may be that the RCR supplied handbrake is the best system for me to install - just trying to make sure of that before moving forward with it...

Chet
View attachment 119312

Chet, they look like Wilwood spot calipers.

Here is a link I found..
 

Chet Zerlin

Supporter
Joel you are spot on (pun intended!). As I get more info I will give Wilwood a call. Perhaps they offer a different "spot" caliper that would work better and still be able to utilize the RCR supplied bracket and cables....

Kyle, it's kind of telling that I've not yet heard from anyone who said they are satisfied with the system. Having not installed it yet I can't speak to exactly why - just want to fully vet it before I go though the installation process.

Like I said the most often issues I've heard (read?) were as I described in my post above. And I am assuming that backing the pad adjustment bolt off sufficiently to prevent contact with the rotor resulted in insufficient pressure of the pad against the rotor when engaged. There were also posts that mentioned having to remove material from the caliper as it would wear a groove where it rubbed against the wheel. However that may have been related to an earlier version of the RCR bracket since that was mentioned in a post several years ago.

So if there is anyone out there that has gotten the RCR40 handbrake system to work sufficiently for their use could you please chime it? Honestly I'd much rather just install what I have than search and pay for another solution....

Chet
 

Joel K

Supporter
I still haven’t installed a parking brake on my car, in Florida there are very few hills. However I still want to do it for the occasional time I need one.

Let me ask, how is everyone engaging the effectiveness? For me I would say that as long as it holds the car, with it in gear from rolling down a hill, then it’s plenty effective. Are they so weak that they won’t do that?

Kyle, I agree with you. If it holds on a hill your probably good. Also, you could apply it and try to drive forward to get a sense for how well it is holding. I have a large torque wrench and since the axle nuts are already torqued to 250 ft-lbs I will put that on the nut and see how much torque it will hold.

Also, since your car is at Allan’s, you should get his perspective. From what I understand he has gotten them to work well with a linear actuator.
 

Kyle

Supporter
Kyle, I agree with you. If it holds on a hill your probably good. Also, you could apply it and try to drive forward to get a sense for how well it is holding. I have a large torque wrench and since the axle nuts are already torqued to 250 ft-lbs I will put that on the nut and see how much torque it will hold.

Also, since your car is at Allan’s, you should get his perspective. From what I understand he has gotten them to work well with a linear actuator.
I never actually had one when I bought the car, so the option on what to use has always been open to me. I’m leaning toward the Tesla, but I will figure it out when I have the tools/time to make a custom bracket. I think all in Tesla with the caliper, and pantera kit it’s something like $400.
 
So if there is anyone out there that has gotten the RCR40 handbrake system to work sufficiently for their use could you please chime it? Honestly I'd much rather just install what I have than search and pay for another solution....

Mine worked fine on my RCR40. I tested it only once on a pretty steep incline.
 

Joel K

Supporter
I never actually had one when I bought the car, so the option on what to use has always been open to me. I’m leaning toward the Tesla, but I will figure it out when I have the tools/time to make a custom bracket. I think all in Tesla with the caliper, and pantera kit it’s something like $400.

Ok, makes sense. Then you have some good options.
 

Ron McCall

Supporter
I've used most of the ones available( Wilwood, IPSCO, RCR ) with less than stellar results. I used the RCR setup on a customer's GT-R but with an E-Stop actuator. It worked ok but would not stop the car while slowly drifting down the hill next to my shop. I've recently installed a few of the Tesla calipers with the Pantera Electronics controller on some Panteras and it will easily stop the car while rolling!
I understand that Wilwood is working on a similar setup at the moment.

Ron
 

Kim Haun

Supporter
This is a timely thread as I had planned to post regarding this to find out tricks or tips to making the RCR hand brake system function better. With much fiddling and some modifications, the best I can get out of the system is a snug drag...enough to where I can’t push the car by myself but not enough to keep it from rolling on a moderate grade. I have a steep driveway and really need this system to work well. From this thread it looks like I’m not alone in needing help. I was thinking that fabricating longer actuating arms on the caliper would produce more pressure. But I can’t remember if there’s clearance for that or not. I’ll have a look later today when I’m at the car. Perhaps Fran can join the conversation with any pointers to optimizing the function of this system?

Kim
 
Chet,

mine seems to work just fine, I installed it per the manual. My driveway is fairly steep and it holds the car very well. I’ve never had any issues with it hanging up either. Unknown on the long term effects because the car has only been driven short distances.
 
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