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PostPosted: Thu Mar 08, 2018 2:26 pm 
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So, now that things are starting to get warmer, I am starting to review the list of things I'd like to improve on my racecar. One of which is brake pedal feel. I still run the stock braking system (complete) and would like to improve pedal feel as well as add the ability to adjust the bias of the rear wheels. I have long coveted having a tilton pedal set and think that now might be a good time to do so.

That said - are there any issues with the firewall mount? Would there be too much flex there? Or am I better connecting this to the cage and keeping the master cylinders inside the car?

Room in the engine compartment isn't necessarily at a premium, but getting the MCs out of there would make engine changes that much easier...

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Bill H
92 Saturn SL2 - SCCA F-Production


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PostPosted: Thu Mar 08, 2018 2:34 pm 
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The firewall on any decently modern vehicle, which was subject to any standardized crash testing, will be plenty strong enough.

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PostPosted: Thu Mar 08, 2018 3:48 pm 
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Yes, the firewall should be plenty strong enough.. HOWEVER, you should heavily consider the servicability of these parts in said location.. I installed a Wilwood pedal assembly in my STU car and because STU still requires a stock dash cover, I have limited access to everything. in order to reach the master cylinders, I have to either stand on my head and will my forearm to grow one more joint, or remove the dash and still stand on my head.

A 'simple' master cylinder replacement in my car is about a 2 hour job and I have to remove the entire assembly from the car, which means opening front, rear, clutch lines.. For most sprint racing it's not a problem since you can usually pump the brake pedal and finish a sprint race if a master cylinder seal starts going south. I started racing the car in WRL (endurance racing), so that 2 hr job took us from top-5 to pretty much dead last in class (outside the other people with major mechanical problems). Then the next driver got in the car and bent something in the assembly, so we put the car on the trailer and drove home where it's sat since November.

Point is, be careful with access using a firewall mount setup with master cylinders inside the car. a prod car that doesn't have a normal dash will make it easier, but access is still something to consider.

If you can, you might consider a floor-mount assembly where the master cylinders are in easy reach.

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Matt Blehm
Houston Region
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PostPosted: Fri Mar 09, 2018 7:26 am 
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Location: Oregon City, Or.
Consider adapting something like this. http://www.cncbrakes.com/Product.aspx?g ... subseries=

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PostPosted: Fri Mar 09, 2018 7:38 am 
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I wonder what it would take to mount that to the Honda!

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Aaron Johnson
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PostPosted: Fri Mar 09, 2018 8:57 am 
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Joe Harlan wrote:
Consider adapting something like this. http://www.cncbrakes.com/Product.aspx?g ... subseries=


Interesting. Looks like a nice piece of kit. I'll have to look further at that over the weekend.

Is there any advantage (assuming there is room) to having the MCs/reservoirs inside the cockpit? I do not have a roadster, so everything would be protected under the windscreen/roof. I ask because, as I survey the prod and GT field, it seems as those most have them inside the cockpit area...

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Bill H
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PostPosted: Fri Mar 09, 2018 9:14 am 
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Advantage is heat and room in the engine bay, Unless you can remove the top of the dash and windshield to gain access I have found no real benefit. I am making something like this unit for my Vintage Firebird so I can maintain the stock dash.

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Joe Harlan Member #175515


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PostPosted: Fri Mar 09, 2018 10:20 am 
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As Joe said, I did it to remove clutter from the engine bay and reduce heat in the brake system. In my STU car, I was planning for the eventuality of installing a turbo engine, and the turbo sits very close to the master cylinder in those cars. (within 1/2"!!) They usually require a blanket on the turbo and foil/other shielding on the master cylinder and reservoir to prevent the turbo from boiling fluid and melting plastic. But no turbos in Prod class so that's a non-issue here..

In a non-turbo car, you still have heat from the header to deal with.

Moving the master cylinders inside creates a packaging and serviceability issue under the dash, but there are floor mount assemblies that make that a potential non-issue. I must admit I have not been entirely pleased with the reliability of my Wilwood setup. I've replaced multiple leaky master cylinders, and it's a major pain given the location. the OEM master cylinders had way better reliability than the Wilwoods. (the Wilwood lasts about 3 years before they start leaking and acting up. they're cheap to replace, but it's the effort required that's a pain.) I considered going back to OE setup on my car, but I welded holes shut on the firewall and a couple braces across the openings to stiffen things up.. it would be major work to go back now.

If you want to look at the floor mount stuff which gives you easier access to the master cylinders, consider the Tilton 600 and 800 series pedal assemblies. http://tiltonracing.com/product-categor ... 00-series/ They are going to be 2x the cost of the Wilwood stuff, but I haven't heard of the longevity problems with them as I have with the Wilwood products.

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PostPosted: Fri Mar 09, 2018 11:10 am 
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I did something similar in my car.
https://www.motorsport-tools.com/vw-gol ... inder.html

Be aware that doing this, and using the OEM pedal assembly will likely result in a rock hard pedal with very little braking force because the pedal ratio on a power brake setup is pretty different from a manual MC setup.
My first session at Indy I stood on the pedal with all my might before I gave up and tossed the car too fast into every corner of every lap in the session.
A ruler, a calculator and a a drill were all it took to make it stop with great feel in the next session (for 3 laps before breaking a wheel center...).

I am concerned about firewall flex, and will be adding some reinforcement to combat this.

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PostPosted: Tue Mar 13, 2018 1:52 pm 
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Location: Buellton Ca.
http://tiltonracing.com/product/600-ser ... -assembly/

http://tiltonracing.com/wp-content/uplo ... _5054A.pdf

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Gary Semerdjian
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Last edited by corradoracer on Tue Mar 13, 2018 2:03 pm, edited 2 times in total.

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