Just watched the autocross videos from your last few events, good stuff. Sorry we missed you guys at the ECR Toy Run, but the
PRI Show was that weekend and it was worth it. That TMS road course event was hairy, and that spitting rain was hitting all of us all day. Your driving looks good, the car looked good, but I saw a few small things that can save you a second or two on a typical run. Let's co-drive at an event again next season, and ride with each other on every run, and I can show you what I mean. My comments are not meant to be disrespectful in any way, just have some ideas where you can gain time.
Those gears... yea, the MT82 equipped 5.0 Mustangs really need the taller 3.31s to have enough speed in 2nd gear (and avoid a lot of 2-3-2 shifts) for autocross. That limitation is costing you many tenths on almost all courses, and I noted this when I drove it before. An easy fix: raise the rev limiter! (kidding!) I know you tried to get on our shop schedule and we couldn't make the timing work on the one day you had free, but that gear swap should be high on the list for next season if you are going to keep autocrossing. If you stay in STU/ESP (probably smart) you can choose between 3.31, 3.55 or 3.73, and either the 3.73 (you'd do more runs in 3rd) or 3.31 (almost always 2nd gear) would be better than the 3.55 you have. You're just lucky like that.
As for the "1/2/3" car builds/buying choices... its hard to say what the "right" choice is? You know how I feel about C4/5/6/7 Corvettes, and the weird reasons I'm not allowed to own one anymore (have owned and/or raced them all, though). Amazing chassis, every one, and you would be faster on track and autocross with any of those models. I rode in McCall's BSP prepped C4 above at the TMS road course and it is a BEAST, but for a street car it is an awful mess. The C5 is better in many ways, but still a major rattle trap. The C6 is niiiiice, and a C6 Z06 is a real option that shouldn't be ignored (well, if you can get past the $40K prices for used models).
The suspension on even the earliest 1984 C4 model Corvette (1987 shown above is very similar) is so much better than a McStrut/solid axle car, and the later Corvettes are even better. The C7 doesn't make a lot of sense (heaviest, most expensive, too new) but a C5 Z06 is cheap and stupid fast. For classing reasons... hell I'd still get the Z06, A Stock/A Street/STU be damned.
But you also need to understand the many
downsides to owning and driving these Corvettes, especially on the street. The driving position just flat out SUCKS - you are practically laying down flat in them compared to the S197 (this is one reason our BMW LS1 swaps are so popular - all the performance of a corvette but with a normal seating position and lots more interior room). Then there's no trunk (except C5 FRC/Z06), no back seat, and the remaining interior room is tight. Adding racing seats to a C4/5/6 with interior is a TOTAL NIGHTMARE (that C6 seat/harness install above takes 3x as long as on a Mustang!), and certain width seats simply will not fit without cutting/removing carpet and door panels. If you want to run a Corvette on race tires you are almost certainly going to need a truck and trailer to tow it with, as stuffing another set of tires/wheels inside is impossible.
The brakes are nice but pads and rotors on some models can be quite costly. The C6 Z06 brakes are particularly expensive to run with SIX brake pads per front wheel. A popular "upgrade" is to downsize these to StopTech 4-piston calipers that use a more normal 2 pads per caliper. And if you have the optional Ceramic brakes (Z06 or ZR1, shown above), get ready for major sticker shock when those need to be replaced. Everything about the C6 Z06 or ZR1 costs more to repair - Awesome performance comes with an awesome maintenance bill. So know that it ain't all roses and sunshine.
The nice thing about the S197 is there are a LOT more of them, so the aftermarket support is much bigger and the costs on parts are generally much lower. They have a great seating position, lots of interior room, a real trunk, and the '11-14 models (at least) all have very queit and squeak/rattle free interiors. Our 2011 GT doesn't make a single squeak even after being flung around on 12" wide race tires for years... these cars are SOLID. Yes, they are heavier, but go drive a used C5 Corvette and you will know exactly what I'm talking about. It will sound like a rickety old wooden bridge on the street.
You know the Mustang, you own a Mustang, and upgrades are endless. You could spend the next 10 years tinkering with that car and never run out of fun things to do to it and with it. And as we've shown, even with high curb weights (and we run ballast for our TT3 class) a Mustang with the right set-up can hold its own with Corvettes, Vipers, 911s and the rest.
There isn't a perfect autocross/track/street car - doing multiple things will always make for compromises. If you want to go FAST at an autocross you need a tiny light car, and power means almost nothing. When people get very competitive I always tell them that they should concentrate one car for one type of event: get a dedicated autocross car, and if you want to do track events, make a dedicated track car. The two sports have conflicting goals, and use different set-ups. You have to pick your most important sport and focus on that for a given car...
Remember how badly the BRZ crushed STX and STU that one time we ran it at Crandall? The car was fast because it was 1000 pounds lighter than a Mustang. All the driving prowess, parts, set-up wizardry and voodoo in the world cannot make up for
1000 pounds. You want an FTD autocross machine we can talk about a Lotus 7, and a "Lowcost" can be built very cheaply (Jason here at Vorshlag has experience racing/owning/building those). Or just get a really light Miata. Its sad, but
weight always wins in autocross.
But you've got a helluva package in your Mustang right now. It is still a nice street car, great track car, and damned good autocross car - and with both street tire and R-compound wheel/tire set-ups you have a lot of options where to race it. Do some more HPDE events and see how you like it before you delve into any more radical mods there, and keep driving. More seat time will only make you faster. The new Mustang is going to take some time to get up to speed, as it has all new suspension at both ends, including the move to IRS. I think it will be heavier, and of course being brand new it will cost more. Lots of unknowns, and racing an S550 competitively is, realistically,
at least 12-18 months away (I've had to come to this sad fact, and am building an interim car to bridge that gap).
Anyway, that's just my two cents... keep at it with what you've got.
