1970 Swinger Build Thread (PURISTS BEWARE)

Mason Coughlin said
Right, that's why I need to wait until I'm getting the K Frame built to know where I will put a shock mount. I've seen where some guys even have built a shock tower of sorts to help brace the factory shock hole, but I still don't like the idea of it.

I would love some more info on that limited slip, any information helps. I've been looking stuff up for months on this before posting the beginning of this build so I figured it's time to post what I'm doing to help contribute to this fantastic data base of information we call "For A Bodies Only".

As far as the track width thing, I have yo build a K frame to mount the C5 lower arms to so the track width can be whatever i want it to be. There's no reason I can't narrow things up over the Vette parts and actually have to anyways because the wheels are zero offset and I want to use a Mustang 2 steering rack which is much narrower and I would run into severe bumpsteer issues if I kept the Vette track width.

The C6 rear end idea keeps growing in me, but I'm not even sure howni would mount a rear subframe to bolt the center section and arms to. I guess I can look into the Heidts kits for Novas and Camaros to get a better idea how they do it. He did say he would cut me a deal and sell the C6 rear stuff for $300 if I took that too... Hmm.

this is copied from my emails from Ron Sutton:

"Differentials

For the track, I run & recommend Detroit Lockers, because they will handle 600-900hp, hard launches & aggressive shifting ... live ... and completely disconnect the inside rear tire in the roll through zone of a corner ... then re-engage like a spool on corner exit. BUT most people find the loud clunking noise very distracting & annoying for everyday street driving.

For a more civilized approach on the street, especially with daily drivers, many people prefer a tamer Detroit Wavetrac, Truetrac, clutch or cone style positraction. None of these will hold up like a Detroit locker, but they behave more civilized. Any differential, that doesn’t fully & completely disconnect the inside wheel from power … is contributing to a tight handling condition in the middle of the corner known as the “roll through zone.”

"Most" of the small helical gear type differentials use a method of pre-loading the unit which affects how the power is distributed under throttle on corner exit. And unfortunately they wear ... and as they wear … and the power distribution changes ... making the car handle differently on corner exits. Not good.

For track performance, nothing beats a Detroit Locker ... with the right spring rate in it. In racing, we tune the lockers with different spring rates from 25# to 125#. (See locker springs HERE) The softer the spring the easier it releases when turning. The stiffer the spring, the more it takes to get it to release.

New stock, off the shelf Detroit Lockers come with too stiff of springs (78#) for what we do, so they need to be changed. A lot of guys are finding deals on used lockers, but the challenge with buying a used Drag Race or NASCAR locker is you don't know what springs are in it. They are easy enough to take apart & see ... or replace the springs. On big tracks like Daytona & Talladega the last thing you want is for the locker to release. So they run the 110# to 125# springs. If you bought a used NASCAR locker with that much spring rate, it would be a bear to get it to unlock. With street tires, I don't think the tires have enough grip to force those 110# to 125# springs to unlock consistently ... if ever ... and would on occasion/often simply slide the tires instead. Drag racers typically leave the stock 78# spring in, which is still too much spring rate for what we do here. For road racing & autoX, the hot ticket is softer springs. The key to picking locker springs is based on rear tire grip. The less you have the softer the spring needs to be.

From my experience, this is what I recommend …
• 40# ... Street, autoX & track cars with 10"+ TW200 street tires.
• 55# ... Track cars on 10”+ slicks & race cars.

As a rule of thumb, you can go softer 1 step, but don’t go stiffer. The key to making lockers work well is getting them to disengage in tight corners. Of course they need to re-engage too. So you wouldn’t want to run way too soft of a spring. Having said that ... there is no disadvantage to running a 40# spring with slicks on road courses. My Warrior cars come with 40# springs in the locker, so they perform just as well on TW200 tires as they do on slicks. "