parking brake caliper to compliment big brake conversion

Well, thanks for the complimentary words and you are right about the costs. I've had several people ask what it would cost for us to do it on another 308 and I just told them to forget about it. I stopped counting a long time ago but the price would be more than the value of the unmodified car. Speaking of modified: I've been careful to keep most (99%) of the work reversible back to stock. The remaining 1% is where you can't see it and can be changed back with a little fabrication work.

 

Tubular A-arms would definitely be stiffer than the OEM open channel construction. The problem,as I see it though, is that the rear sub-frame on a 308, which the A-arms connect to, is not as rigid as it can be and the rear stub-axles are known to fail under racing-type loads. I don't intend to ever run this car on slicks, which can generate significantly higher cornering forces, so hopefully everything will survive. If you're going to strengthen links in the chain you've got to look at all the links.

I did stiffen the arms a bit by welding-in triangulating links here and there between the U-channels and the center pans and I drilled lightening holes in parts which I figured would be under less stress. Under a steady cornering load, the lower A-arm at the outside wheel is under a compression load while the upper arm is under tension but to a lesser degree.

Among other modifications in the plans are a "strut tower brace" between the upper shock/spring mounts to help stiffen the rear sub-frame.

 

Right now I'm in the process of trying to get us into a bigger building so that kind of shoots the machine toy budget but I'm very interested to see what you have. Can you post pictures and a link? Thanks in advance.

 

Yeah, it's funny - with all the work I put into that car I get the most positive comments about the grille. No I've never posted anything about the grille in particular.

Actually, we get a McMaster-Carr delivery almost every day and most likely they sell the material but it's 1/2" (12mm) stainless steel screen (hardware cloth) from Pegasus racing, wrapped around a frame made of 3/8" (10mm) round aluminum rod (#3003 "alloy" I think).

 

I actually googled that set-up last night. It's basically a retrofit kit for a Bridgeport and it's clones. I like the fact that it apparently comes with new ball screws for the X and Y table feeds. My machine's feed screws are getting sloppy. Without a DRO they'd be close to useless. Yeah any information would be appreciated. The website didn't tell much. I have no CNC experience but I once looked at a small CNC mill that had pre-programmed shapes like a cube, a hemisphere, half an egg, etc that you could change length, width and height on. That was pretty interesting but the guy changed his mind about selling it and I moved on. My DRO will guide you through circular bolt patterns by the way.

I'll take some pictures of the grille and post them here.

 

Thanks Mark. I generally don't like sliding-pot brake calipers but I was half way through with these and decided I should have made these parking calipers sliding-pot. Having too much work into them to just start over, I continued with the design I had. The calipers I made work very well but they could have been even better and even lighter.

 

Sorry to take so long but here are some photos of my 308 grille. In the close-up you can see very small stainless alen-head machine screws, to the left of the parking lamp, that attach the grille to the car via specially made brackets. Like I said before: The stainless hardware cloth is wrapped around a frame made of 3/8" (10mm) aluminum rod. The lights are generic sealed, throw away, truck/trailer lights. I wanted long narrow vertical lights so the air to the inter-cooler heat exchangers would be blocked as little as possible.
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I have no idea what she weighs at the moment. I have a set of race car scales and used them to set corner weights a while ago but didn't really pay too much attention to the total weight because it is is what it is. I'll have to check it out one day. I reduced weight here and there but also increased it here and there. The car has no spare tire, an aluminum radiator, lighter fan, no more carburetors, no distributor, a lighter exhaust system, a lighter AC compressor, etc but the super-charger and the bigger brakes are not exactly light weight. I want to make a carbon fiber engine cover a front trunk lid. The steel engine cover weighs a ton and sits up high and in the back where you don't want weight.

 

That's funny, I bought used calipers too. I bought the the front and rear calipers and 4 front rotors for a Porsche 996 (I think) Turbo at Porsche Recycling in LA. The stuff came off of low mileage wrecks and was good and not too expensive. I made the hats from aluminum billet. My master cylinders are Tilton but I bought them new.

Speaking of budget brake systems, I scratch built a sports car using Maserati Quattroporte III mechanicals and I'm upgrading the brakes on that right now. I inherited a set of Brembo calipers that came off of a customer's Diablo after installing even bigger brakes on that car and I'm mounting them over Wilwood racing disks with Wilwood aluminum hats on custom made 7075 aluminum hubs. The Wilwood hats came with a 4.5" wheel bolt circle that fits right over the Maserati 115mm wheel stud circle.

 

What, you cant do that with hand cranks? Just kidding. That's great!

 

You can buy O-ring string in all sizes from industrial suppliers. The best is Viton. It's usually brown.