track car build brainstorm

LeVeL

LeVeL

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I've been thinking about cars that would make great track/autocross warriors, yet would still be street legal.

LSx RX7 has better weight distribution and can fit wider tires than an LSx Miata.
But then again is that really better than just getting a C5 (coupe or Z06)... also 50/50 weight distribution (like the RX7 would have), also wide tires, same motor (LSx), and not much heavier.

MkIV Supras are easy to get power out of but they are really heavy.

Elise/Exige = no torque. I'd probably want something faster as a project car.

Cayman/Boxster - you can't get to the engine without a lift.

NSX would be amazing but it would need a supercharger, which means $$$$.

M3s get expensive very quickly, although an E36 would be pretty cool (maybe with an LSx :evil:).

What else?
 
Torque isn't super important on a track. You just keep it up at the power band.
 
They sell some pretty badass supercharger kits for NA (body style not aspiration) miatas, I would prefer that over an LSx miata.
 
I would vote for doing everything to get weight down. Power just isn't a big deal on the track. Cornering speed is what's absolutely a blast.

If it has to be street legal... You are really urinating upwind with anything except a Miata. The RX-7 is okay...but the newest 1st gen RX-7 is years older than the oldest 1.6 Miata. Unless you already have deep RX-7 sources and knowledge, I'd avoid it.

And a Miata built to IT (Improved Touring) rules (which are much less restrictive than SM (Spec Miata)), which allows coilovers, etc., and with pure racing tires (not the DOT-R required in SM) is going to be really quick.

Also, being less expensive, it's easier to drive it right at the limit, since you can afford the mistakes compared to a Cayman. (and if you can afford to write off a Cayman, you should seriously consider a pure race car, which will be even faster, more fun to drive)

Steve
 
If you're going for lightness, there's always the MR2 Spyder. It's almost as light as an NA Miata (according to Wiki), though newer and pricier, and the hardtop is much harder to find. MR cars do have a higher learning curve than FR ones, as I found out a few times.
 
C4 Vette... Cheap to buy and it is a well known auto crosser...
 
LeVeL said:
LSx RX7 has better weight distribution and can fit wider tires than an LSx Miata.
But then again is that really better than just getting a C5 (coupe or Z06)... also 50/50 weight distribution (like the RX7 would have), also wide tires, same motor (LSx), and not much heavier.
Click to expand...

Engine-swapped cars are a bad idea for any kind of sanctioned (SCCA/NASA/whatever) event. You'll likely end up being put into a Modified class, where the drivers are generally much more talented, and the cars much better prepared overall. The end result is that you'll probably be slapped silly at every opportunity.

If you're dead-set on doing this, my recommendation is to read up on the rulebooks in the events you want to enter; that way, you have an idea of what you can and cannot do to your car for it to fit into a certain class. But beware - as I said before, the higher class you enter, the less likely it is for you to succeed at it. Personally, I would try and find a Miata, Honda CRX or an E30/36 BMW and just race it with some minor preparation - stickier tires and maybe some suspension work (if it won't put you into a Prepared Class).
 
MR 2, Miata, E30 -boring but obvious choices.
 
Get your hands on a Honda S2000 if you can, they are great fun on a track. :)
 
V8 swaps are a bit of a novelty, you never see them at the track (unless it's a drag strip.) And I don't care what people say, you will be making a sacrifice in reliability.
 
MrChips said:
Engine-swapped cars are a bad idea for any kind of sanctioned (SCCA/NASA/whatever) event. You'll likely end up being put into a Modified class, where the drivers are generally much more talented, and the cars much better prepared overall. The end result is that you'll probably be slapped silly at every opportunity.

If you're dead-set on doing this, my recommendation is to read up on the rulebooks in the events you want to enter; that way, you have an idea of what you can and cannot do to your car for it to fit into a certain class. But beware - as I said before, the higher class you enter, the less likely it is for you to succeed at it. Personally, I would try and find a Miata, Honda CRX or an E30/36 BMW and just race it with some minor preparation - stickier tires and maybe some suspension work (if it won't put you into a Prepared Class).
Click to expand...
I'm just brain-storming, I'm not actually doing this... at least not any time soon. Actual short-term plans do include a mildly modified Miata.


Lightning Count said:
Get your hands on a Honda S2000 if you can, they are great fun on a track. :)
Click to expand...
I cant stand driving them on the street, although they sure are fun at autocross.


Twerp128 said:
V8 swaps are a bit of a novelty, you never see them at the track (unless it's a drag strip.) And I don't care what people say, you will be making a sacrifice in reliability.
Click to expand...
A stock LS1 will be less reliable than, say, a 13b?
 
A LS1 without sufficient cooling would be. It all depends on how well the swap was done.
 
A friend of mine has a LS1 FC that he daily drives without a problem. Total cost to build the car was about 12k including chassis and TII rear swap. IIRC it weighs in at 2800lbs with full interior.

A v8 miata seems cool, but EVERY single one I've seen with weight posted on the web all come out to 2500-2700lbs. Once I saw the weights of the cars I got HUGELY turned off from the idea... it's why I'll eventually going turbo with the 1.6 if I ever bother (they don't seem to make all that reliable of track cars with boost).

Why LS an M3? Start out a bit cheaper and go with a cheap ass e36, or better yet the 318ti. 318ti is the lightest of that chassis but can still take all the e36 upgrades. If starting with an m3 why not just throw some boost at the S50? Or Throw boost at an M50 325?

On that subject, e30 with an M/S50 swap? M50 non vanos motors are cheap, cheap kits are available to swap the motors, and they take to boost well. It's not hard to strip one down to under 2800lbs even with that thing in it.

You could also try a 1jz swapped MKIII supra :dunno: Fairly adjustable double a-arm front and rear suspension, engine can take a boat load of power, as well as the driveline, and the suspension options for the chassis have picked up over the years. Only downside really is weight, about 3300lbs with full interiors

Personally I like the idea of the V8 RX7. It's the lightest most powerful of the options, and the FC does have a healthy aftermarket for it. Now since I already have the miata I'm gonna enjoy learning to drive it properly quick then toss some power at it.
 
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Or buy an old MGB or Spridget (unibodies are your friend) and swap in a 302 SBF/Rover V8 (for the B) or a Toyota 4A/Mazda Wankel (for the Spridget).

With the B you will at most be 2,000lbs. The 302 is a bit heavier but you'll be replacing the heavy bronze radiator and other crap in the process. The Rover V8 is a good option too as it weighs less than the original 1.8L B series engine.

Spridgets are a bit more limited. A series engines weight next to nothing, so you need a real feather weight. Rotaries and the Toyota 4A series have fantastic power to weight ratios (for the Toyota get a 5 valve).
 
argatoga said:
Or buy an old MGB or Spridget (unibodies are your friend) and swap in a 302 SBF/Rover V8 (for the B) or a Toyota 4A/Mazda Wankel (for the Spridget).

With the B you will at most be 2,000lbs. The 302 is a bit heavier but you'll be replacing the heavy bronze radiator and other crap in the process. The Rover V8 is a good option too as it weighs less than the original 1.8L B series engine.

Spridgets are a bit more limited. A series engines weight next to nothing, so you need a real feather weight. Rotaries and the Toyota 4A series have fantastic power to weight ratios (for the Toyota get a 5 valve).
Click to expand...

Wait lets go combine your ideas with mine and Levels...

91 miata (lightest) with a rover/buick v8... Small compact car with a small compact engine capable of 300+hp. Start with this front subframe http://www.v8roadsters.com/category-s/98.htm and you shave weight off the factory subframe and can weld any mounts you want on it :D

I actually thought about this once before, but no way to make that swap smog legal here in CA.
 
^However, 2ZZ MR2 Spyders are smog legal, provided you get the years of the car and engine donor to align properly.
 
miata, every other rx mazda, exige/elise and Porsches. nothing else thats affordable comes to my mind. Maybe a caterham or ariel atom. As your platform, you want something that handles good and is light. You dont want an M3 as you would have throw everything out of it and that cost $$ and is time consuming. its easier to make a car more powerful, rather then make it lighter.

EDIT:
I think I got that quote from another user from this forum:

Colin Chapman (founder of Lotus): "Adding power makes you faster on the straights; subtracting weight makes you faster everywhere."
 
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