GTs 58

I was under the impression that the FRC was going to something special from day one. My Lady's Son was working at GM's Mesa Proving Grounds during the time the new C5's were being introduced. He was a test mule driver and he gave me the heads up that GM was planning a special Corvette for the track. When the FRC was finally introduced and I read up on it I said what! He replied, just wait, there are plans for that Corvette. From his insider tease and lack of solid information at the time, I believed the original plans for the FRC was the Z06.

v8srfun

If I found a smoking deal on a yellow one I would have bought it but yellow stands out to much for me. All the other offered colors blend in more but you are quarantined to be noticed in a yellow one. I try to attract as little attention as possible when driving because I already get enough.

dbgoodwin

I like how the original post was just a funny comment about how many times the acronym FRC is used in the C-5 world and now everyone's getting all nitpicky about the fixed roof coupe specs.

Scylla

This article is helpful if you're curious why the FRC exists: http://www.superchevy.com/features/1...rvette-models/ I'm not sure if FRC's will become collectors items or not but much of the attitude here is wrong headed. If you lose the tear drop rear glass, the aerodynamics of the car are very significantly impacted in a negative way, you're close to a rag top.

I think it's miss-leading to consider the FRC a performance upgrade, since if two cars with the same HP go up against each other, with marginal differences in weight, the one with better aero will always have an overall advantage except at very low speeds. I looked into all this when I bought my car, the rear hatch window also is part of the weight balance in the original coupe, which was not properly offset with other weight losses (also notice the location of the rear glass, you don't actually want to move weight away from there, just maybe downwards). Now none of that is a huge deal, but it's definitely not an advantage either. Check the math on how much HP it takes to get to 100mph, it's more than a mod or two to make up.

If you like the FRC's style, great! But it was a little bit half-baked, Z51 was a good improvement over base, but that was available on all models and most of our cars on the forum either need or have new suspension. The FRC had standard Z51 sway bars as well, only the front leaf spring is shared between Z51 and Z06.

Bob Beroza

The FRC was supposed to be the "Bad Boy's Corvette, a low priced, low optioned Vette that was meant for racing. But the C5R ended up using the coupe because they couldn't fit all the racing electronics etc. in the trunk area. The FRC was 1 out of ever 2 Corvettes because the price of a coupe with the std tradition and Z51 options was only $1000 less than the coupe. The ZO6 went up to 1 out of every 7 Corvettes because it became the Bad Boy car but not with a budget price.. I always thought that the reason they put the ZO6 in the FRC was to amortize the dollars that they spent in parts contracts on FRCs. The fact that they went to the coupe on the C6 ZO6 bears that out.

Scylla

That theory would kind of make sense. The symmetrical suspension on a corvette isn't exactly a bad thing, but the goal was definitely to reduce the number of individual suspension parts by using the same knuckles and stuff on both the front and the back. So GM definitely looks at cost/investment very closely. Maybe the FRC design started as a motorized hardtop convertible design which proved too expensive and they kept working on it?

VetteDrmr

I guess it depends on what you define as "very low speeds". Aero doesn't make itself known measurably until you're well north of 100. You completely missed the weight difference between the coupe and the FRC, disregarded the significant increase in stiffness of an already stiff chassis, and the fact that the reduction in weight was almost all above the beltline.

Don't believe me? Head over to the track forum and ask about RAFT.

Have a good one,
Mike

skydiven4fun

Love my FRC especially when I find a spot to unleash them 640+ ponies, the LS-1 is a remarkable piece of engineering and is capable of making some serious power.
Like I said I love mine and she's going nowhere although she may get a brother soon.

Gordy M

When the FRC was first introduced, we had a speaker from the Performance Group talk to our club about it and why it was introduced. The harmonics of the C5 convertible was 22 and the coupe was 24. For SCCA club racing they wanted a stiffer chassis and had to have a fixed roof. If you removed the roof of the coupe the chassis stiffness was reduced considerably. The fixed roof option was brought out and and the weight reduction of the other articles previously mentioned resulted in a Corvette with a stiffness of 26. For racing they thought the first thing one would do was replace the seats with a real racing seat, the oil cooler and 6 speed only and the Z51 suspensions were standard. Marketing looked at it and said this could also be a low cost intro to the Corvette market and priced it accordingly. After introduction, all the club racers said they needed HP and the Z06 engine program was started. We had about 5 or 6 members of our club working at Milford at that time and they said the 01 only had 385 hp because the 405 versions had not yet passed all the reliability tests.

Scylla

I looked into all this stuff when I was choosing a car. The weight change is about 75 pounds between an FRC and a base model coupe. The weight is removed from a part of the car where you want weight centered to maximize your stability while cornering... there is only minimal gain there if any. The difference in aero doesn't just affect high speed, the increase in drag created by the break in the swoopy contour you get with the standard coupe will affect all speeds, but be particularly detrimental to stability over 100mph since the C5 coupe's design is aerodynamically brilliant. The rear end does most of the work of a wing by itself, which is why many people with track C5's simply don't bother with a wing. By comparison Z06's and FRC's typically do require wings in high performance applications, so add that weight in.

A C5 FRC is a great car, but from an engineering point of view the changes compared to the standard coupe were not entirely positive... It is more rigid, but the C5 coupe was already extremely rigid. Having said that the base suspension in a coupe is garbage (gooshy boat when you corner) . I purchased my car with the intention of making it a lightcore, daily-able track car. So I bought a base coupe and replaced the suspension with a full Z06 transplant. I'm very pleased with the results.

That's what made sense from a performance and cost point of view given my build goals. The main point being a coupe with Z51 and minimal options will outperform an FRC due to the above differences, on most tracks (and in performance driving scenarios more generally). That's why I called the idea half-baked, you compromise your aero for 75 pounds.

The base C5 Coupe is an amazing design, but the Z06 rear brake ducts are another example of where Chevy fell down a little in this generation. The front and rear brake rotors are both curved directional vane, so they pump air through their internal gaps as they spin. the ducts do basically nothing for the rear, but they cause a significant disturbance to aero right in front of your wheels, exactly like you do not want. A Z06 will mop the floor with a standard vette, but it has more power and better suspension. A lot of the external changes actually impact performance negatively. Aero is not just top speed, it's a tax on acceleration at all speeds too, a big fat system efficiency tax.

My opinion, whatever it's worth, is that the conventional wisdom is correct. The C5 is an amazing car, and the Z06 program matured with the C6.

tbrent

Pray tell, how exactly do Corvettes with targa tops lose rigidity?

VetteDrmr

Because the removeable tops aren't tied hard into the roof structure, and therefore the front and rear parts of the roof can move in relation to each other. That's the source of the creaking noise that you hear in some applications.

Anyway, the roof of the FRC is one piece, which adds to the stiffness.

HTH, and have a good one,
Mike

tbrent

The roof is epoxied to the windshield. It provides no stiffness. Stiffness runs in a halo over your head(b pillar), behind the seats and the tunnel plate.

The squeaking etc is just the nature of a targa. All C5's came down the assembly line ready to be made into a coupe, frc or convertible.

Exact same tub.

F actory R ace C ar

VetteDrmr

In the vein of a friendly discussion:

Of course it adds stiffness. It's not just secured at the windshield, but continues past the halo and down to the rear deck. The structural epoxy is just as strong as any other method of securing.

Not exactly. The coupe gets the halo, which the 'vert obviously doesn't. The 'verts get a strengthened waterfall (the part behind the seatbacks) to help get back the stiffness lost from the halo. Not enough (stiffness changes most due to height of the structural member in the overall structure), but pretty darned good.

The FRC gets both. THAT's the main reason for the change in stiffness between the 3 body styles, although I stand by my statements about a solid roof versus a removeable one.

Have a good one,
Mike

tbrent

This is silly we're saying the same thing. Minus your You said the FRC gets them both. So that implies the epoxied roof has nothing to do with the rigidity. If it did there wouldn't be targa top FRC's and Verted FRC's out there.

Like I said the coupe has a halo for rigitidy, a bar(or waterfall if that's what you want to call it though the convertible waterfall is only for aesthetics)behind the seats.

You're passing on bad information.

All C5's came down the pike with the ability to be put out in any of the configurations.

Or maybe all the people I've spoken with(GBvette, Illmac77 and others who have modified their C5's), and all the research I have done to help me decide to cut my roof and make it a targa has been a cruel joke played on me by a lot of people with nothing to gain. While they have ruined their cars in the process.

Seems strange that if you point a heat gun where the windshield meets the roof and pry the roof away that wallah it can receive a C5 coupe targa. Guess GM did that by accident.

So tell me something I don't know or don't.

The C5 was designed to be a convertible. Even though the vert debuted a year after the coupes release.

I a perfect world, yes a flimsy SMC panel glued to a windshield would provide resistance to torsion but it doesn't in the real world.

VetteDrmr

Think I'm going to bow out now.

Have a good one!
Mike

Kent1999

GM's tests and research says the fixed roof *does* add a measurable and significant amount of stiffness. Open car/vert is less rigid than a coupe with the panel latched in, which in turn is less rigid than an FRC. They have the objective engineering test results to prove it. What engineering tests have *you* done or depended upon to confirm your "findings"? Anything other than just driving it and thinking it 'feels' ok, or talking to others who also have done it and say it 'feels' ok?

And just because some people make a decision to slice off their roof, and the car doesn't fold in half -- that doesn't prove anything except that the C5 can exist as a convertible. It proves absolutely zero about the loss of rigidity from that conversion, other than that loss is not severe or catastrophic.

So to use your words, tell me about the engineering test results that refute GM's, or don't.

jjc508520

I love my '00 FRC - it has numerous performance options that I'm still learning about. At track day another '00 coupe owner was telling me how he boiled his power steering fluid and proceeded to show me where my PS cooler (that he had to retrofit) was installed - who knew!

NY~FX

Great Performer Great Platform
Long Live the FRC and the evolution it began!

f6john

Disregarding everyone's research into how a coupe is a better design for all the reasons already listed, isn't it interesting that GM chose the FRC to use in their "kit cars" for racing?

Also interesting that the fastest C5 record holder on the salt flats is a FRC! I suppose if they had done their research they could have used a coupe and gone even faster???