Thanks Andy. I'll keep that in mind as I'm doing the design and math.

My goals are to have fun and learn to drive better. One of my design parameters is to use as many parts as I have on hand in my garage, which as I said earlier comprise a lot of what I'll require.

I'l be looking at some of the various racing leagues, the more entry-level ones, and try and get some data on power to weight ratio's versus speed and time at particular tracks. That should give me an idea where I might stand, and how I might need to adjust my build parameters.

I've read some of your previous posts about turn-of-the-century Corvettes being a better option for a low budget track car, and I mostly agree, especially if you're talking about unmodified, ie low stiffness, 60's 70's Chrysler chassis. However, A full space frame tubing chassis welded onto the existing car changes that equation somewhat.

I don't see that a properly done torsion bar and rear leaf spring design would be a hindrance to track speed. However, you did write factory T bar setup. The one major issue that can't be overcome building a car on the factory chassis is that you are severely limited as to how much you can lower the front end as the lower control arm comes in contact with the frame rail. Historical way to fix that is to raise the front sub frame in relation to the rest of the chassis or as the Chrysler books say "lower the body on the frame". But now we're in a whole nother world of high dollar.
What would be a simple and effective solution would be to use a drop spindle. This is a perfectly acceptable design that would lower both your CG and your front role center. However, I've done the research, and I have to agree that there isn't a good one available. A properly designed spindle, with the proper materials and processes, could be produced by casting. But, I'd need a lot of data like fracture toughness, static load test results, dynamic load life test data, and assurance that it wasn't made in China, to be able to trust it. I don't see getting any of that from the current manufacturers.

So, I will set my performance expectations for what I can do based on what I've got, and have as much fun as I can with that and learn what I can at that level. I'm not looking to set the world on fire (for now). And I will use the Barracuda instead of buying a Corvette because 1. I have a clean fastback chassis I bought for 500 bucks many years ago, and 2. because the Barracuda's cooler.

i'm actually kind of surprised you didn't see any aerodynamic affects over, say, 120. But, every aerodynamic configuration is different. So I'm still going to look into finding whatever historical data that I can. People have been racing this set up for about 50 years. And I'll do my own testing once I get the thing together.

Thanks for your input. I may be sending you requests for lessons learned in the future as I'm working on this thing.

Robert