Thread: B13 Rally Car Build

Yeah, it was depressing, but I move on.

What happened was this. I spent the two weeks building up to the Lake Superior Performance Rally (LSPR) working night and day to get the car ready. The day before I was to leave, I still had a laundry list of things to do, and barely enough time to do them. While bleeding the brakes, I notices the pedal was loose and that one of the nuts on the left side was loose. I was in a hurry and grabbed my impact driver (NOT an impact wrench, I'm not that stupid) and guessed at which nut was loose. Bad idea, bad guess, and the stud snapped off of the brake booster.

I could have run down to the junkyard and pulled a booster, then swapped them, but between the time to drive to the yard, pull a used one, return to my shop, tear out the broken one, install the new one, and start from scratch bleeding the brakes, I was looking at a minimum of 3-4 hours, which I simply didn't have.

So instead I spent the rest of the afternoon swapping new struts into my Outback and drove up and volunteered at the event.

Since I have to start over with the brakes anyhow, I've chosen not to replace the booster. Today FedEx should be dropping off a Wilwood brake pedal box with dual masters and a balance bar. This will eliminate the power brakes entirely and give me separate master cylinders for front and rear, and the ability to dial up any balance between them that I want.

Power brakes are an issue with rally cars, as you only get vacuum when the throttle is closed (or nearly so) and using a left-foot braking technique can involve a lot of brake use without ever lifting off the throttle. For rallycross, that was OK, as I knew I'd lose power assist after the first couple of turns and I was ready for it. On stage, it's a lot more inconsistent, and the speeds are a lot higher, so the stakes are too.



We'll see how much alteration needs to be done to the firewall to mount this stuff. Almost wish I had a hydro clutch transmission so I could use the Wilwood dual pedal setup, which would make the clutch and brake pedal locations consistent.

I also ordered a hydraulic handbrake, since I'll be re-plumbing the entire brake system for the dual masters (and re-routing the lines into the cabin rather than leave them exposed under the car. Fuel lines too).

The handbrake I got was one of the eBay cheapies, which are supposed to be OK except the cheap cylinders on them are famous for not releasing pressure and burning up the rear brakes. I also ordered a Wilwood compact remote master to swap into the handbrake to address that issue.

There's a rallycross near here in a week and a half, that I might take the car out to if I get stuff sorted out. Don't need some of the stuff that isn't done yet to go do that.

You can make a hydro clutch pretty cheaply if you still want to. Have macidcrook take pics of his setup. It's a $70 pull slave mounted on a plate that pulls the stock TO brg arm. I had planned on using one of those if I didn't go with a hydro trans (B15, Spec V or 50V from an SR16), which would be my preference.

Well, that was my plan before deciding to part out. If I had any of those parts I'd send them your way.

The bitch with the B13 chassis (as you'll find) is the steering column is just in the way of everything. Note how much the stock brake pedal is offset to clear the column.

I gave up trying to do a firewall-mount pedal and instead went with a floor-mount clutch/brake assembly. But then again I did this to a road racing car and I relocated the steering wheel and driver's seat rearward.

Good luck!

Argh. Had not thought about that. I'm willing to live with relocating the pedal a bit father away from the throttle (as I never heel-toe and in fact I'd like a little more space to fit my size 12s on the brake and throttle at the same time).

We'll have to see how it looks when I get in there. Haven't had the steering column installed and frankly had not taken it into consideration.

Floor mounted is bad stuff for rally, dust, dirt and sand will muck the pivots and linkages up fast.

I do know a guy who might be able to machine up an offset pedal arm for the Wilwood if it comes to that.

I hear ya there. Worked on many a rally car, crewed for a few teams, used to co-drive for Tim Mather's B13 (1.6 litre though). I would do it for a rally car IF I could isolate the pivots from the environment. Basically build a cover to keep the crap out of it.

The trick with the floor mounts and rallying is to never lube the pivots, keep them dry, and clean them frequently. Oil just attracts dirt.

I got the Tilton setup and found they were surprisingly affordable..$197 for the pedal cluster.

Here's what the stock pedal cluster/steering shaft interference looks like:

Yeah Bob, you're 100% right. I tried fitting the pedal last night and there's just no way it'll work.

Time to look into building a dual master/balance bar bracket to replace the stock booster.

I don't know if this will do much good, but I found it going through some old files. This is an old IMSA Touring Sedan setup by Nissan MS in the US. This car is Macidcrook's car now.

pedal setup | Flickr - Photo Sharing!
pedal setup | Flickr - Photo Sharing! by rallyser, on Flickr

Now that would never work for me. I don't think I could even drive a car with the accelerator and brake so close together. I have really big feet.

You know what they say about big feet.

Big driving shoes...

Ok, so it's been a loong while. Progress has been slow, but happening.

I returned the Wilwood pedal w/ balance bar and ordered up just a balance bar (and added the remote adjuster for the fun of it).

Built a box that fits in place of the power booster that hold the balance bar and the masters. There's a pivot at the top of the box to control the motion of the balance bar, which I welded an arm to. I also welded a tab that goes through the firewall and gets attached to the brake pedal with a couple of yoke ends. Pictures eventually.

I have also run all new lines for the front brakes and bench-bled the masters. The line for the rear has been run to the location for the hydraulic handbrake and that's where things are at currently.