Comparing Corvettes in Sports Car Racing Series...

[pgtr]

I noticed we've now had 3 recent events at Road America in WI. Unless there are any changes to the course for each event - makes for some interesting comparisons...


In Speed WC we have the fastest (race) lap time of:
2:19.589 at 104.398mph by the winning 911.

The fastest (race) lap for a Z06 was:
2:22.140 102.524mph by #35 David Farmer

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In Trans-Am we have a fastest race lap time of:
2:09.558 @ 112.481mph during the race

The fastest qualifying time was:
2:08.143 113.723 mph in a Jaguar.

The fastest 'Corvette' qualifying time was:
2:09.401 112.617mph (qualified Stuart Hayner for 3rd position)

===========

In ALMS we have the fastest qualifying time of:
1:52.265 @ 129.807 by an Audi R8 (LMP900)

The Fastest C5R qualifying time was:
2:01.969 @ 119.480 (Gavin/Collins GTS Pole)

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So we go from
2:22 for a Z06
to 2:09 for a 'Corvette' bodied, tubed race car
to 2:01 for a C5R (how production based it is these days I don't know)

Where a Grand Am Cup Z06 or a more fully prepared Grand Am Rolex C5 fit in - I don't know off hand.

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It's a little difficult to consider the Z06s of Grand AM Cup or the C5s of Grand Am Rolex. They race on France/NASCAR alligned or owned tracks from what I can tell and the arrangement are mutually exclusive. I think Cup will be as Mosport later on - that's it. I'd guess the Cup Z06s to be equal to WC Z06s. I think the Rolex C5s would be comparable to the TransAm cars perhaps but a bit of a guess on my part...

[pgtr]

Also just what degree of mods are we talking about here...?

I know that the WC and GrandAm Cup C5s are mostly production (stock) based Z06s.

The TA Corvettes are silhouettes based on a tube frame race car.

But the infamous C5Rs of ALMS - just where exactly do they fit in? They aren't tube framed like the TAs - but then they aren't hardly production based like the Z06s. Or at least they are heavily modified right?

Same goes for the Grand Am ROLEX C5s I. Heavily modded production based or tube framed...?

[RM40]

Their are Corvettes in GARRA this year, excluding GA Cup?

[billnchristy]

The ALMS GTS corvettes are nowhere near production based, they run a 427ci smallblock made of aluminum, they are a carbonfibre monocoque and body, they have a rear transmission (like a porsche 944)...in other words, purebred races cars made by Pratt & Miller with AER engines...

The GA cars are tube based just like T/A cars, unless you are talking about GAC cars, they are like the Speed World challenge GT cars, or more or less a production Z06 with a cage...

[pgtr]

Thanks billnchristy for the sanity check.

Yep the 7L is certainly not on the option list!? I knew about the carbonfibre but didn't know to what degree - so this almost sounds like a 'silhouette' car too...? Essentially an exotic race car housed in a body that resembles the C5 I gather.

GA Rolex Corvettes sorta similar to TA. Both are tube-framed...

GA Cup Z06 essentially equates to WC Z06s...

Outside of GA Cup and WC - they are all pretty far removed from anything vaguely resembling production outside of 'appearance'. (how different is this from NASCAR?)

[noise boy 2]

Originally posted by billnchristy
The ALMS GTS corvettes are nowhere near production based, they run a 427ci smallblock made of aluminum, they are a carbonfibre monocoque and body, they have a rear transmission (like a porsche 944)...in other words, purebred races cars made by Pratt & Miller with AER engines...

The GA cars are tube based just like T/A cars, unless you are talking about GAC cars, they are like the Speed World challenge GT cars, or more or less a production Z06 with a cage...

Incorrect about the c5r on a number of fronts. The LS6 in the current road corvette is an aluminum block and heads. The transmission in the c5 road corvette is in the back of the car. Katech builds the 7liter variant of the LS6 (which uses production heads and internals, the only change is the bore and stroke), not AER. Robert

[billnchristy]

http://www.americanlemans.com/galler...x/RAalms01.jpg

There is a nice picture for you to see the gigantic AER symbol on the rear quarter of the C5R. The block is not the same as a LS1/6 though it fits the same, it is a big bore small block. The C5R engine package that most companys will build you will cost around 28k, there is nothing stock about that!! As for the tranny, ok I was wrong about that!

[billnchristy]

I guess the difference from NASCAR is that the car actually represents something you can buy.

[billnchristy]

Oops, you were right about Katech, sorry...wonder why the big AER symbol is on the Vettes? any clue as to that?

[paul-collins]

AER on the Corvette is not the same as Advanced Engine Research, the company that builds the MG engines for the Dyson and Field cars. They are engine remanufacturers, whatever that means.

http://corvetteactioncenter.com/hist...2282001_2.html

http://www.aermanufacturing.com/

http://www.aerltd.com/

[pgtr]

Great info! Really appreciate it.

But it's still not clear to me to what degree the basic architecture of the chassis is production based and modded or fabbed up in exotic materials from scratch.

1) Do they take a a C5R chassis from the factory and seriously modify it at a fundamental level using exotic materials?

2) Or do they start w/ building their own racing machine from the ground up and clad it in panels to make it into a Corvette?

thanks,
T

[billnchristy]

C5Rs are purpose built in the Pratt & Miller shop, there was a magazine some time ago that had a C5R and a Z06 sitting next to each other, the c5R is quite a bit bigger and wider, but dimensionally equal, kinda like the old GT40 and the GT40 of new...

[noise boy 2]

Mostly the c5r is wider than the stock corvette, both at the wheel arches and at the shoulder (top of the body) the overall length and wheelbase are shared with the production models. The GTS rules allow for much more leeway in the body modifications than the GT rules. The Prodrive & raffanelli 550's have been modified in much the same way from the street version, as has the viper. The idea with the GTS rules is that the car has to retain it's production character (unlike the Trans am cars which look nothing like their production counterparts, other than the headlight and tailights IMO) Robert

[pgtr]

Great info! Really appreciate it.

But it's still not clear to me to what degree the basic architecture of the ALMS chassis is 'production based' and modded or fabbed up in exotic materials from 'scratch'.

1) Do they take a a C5R chassis from the factory and seriously MODIFY it at a fundamental level using exotic materials?

2) Or do they start w/ BUILDING THEIR OWN racing machine from the GROUND UP and clad it in panels to make it into a Corvette?

thanks,
T

[noise boy 2]

I believe that they start with an actual corvette chassis from bowling green, then build up the car around that. Robert

[corvetteracing]

The C5-R is based on the same hydroformed frame rails as the street car. The chassis are not made at the Bowling Green factory but are developed by another supplier.

[pgtr]

Thanks!

[Splatz the Cow]

Noiseboy is correct there about how they started - with a corvette sitting in the workshop and just went from there, to the full extent of the rules (worth checking out), ligntening the car, stock engine bored out to 7litres (they originally raced with the 6litre against the Vipers and got spanked because of it), wider track front and rear to max limit of rules, and stiffening the car. Suspension was also different if I remember to survive the races. Ends up weighing around 1100kg.

[David]

On my trips to the Pratt & Miller shop and my visits with the #4 crew chief and visits to the Corvette pits, I have been told that GM dictates that the C5-Rs must be built using two hydroformed frame rails, a stock windshield shape, have a stock width across the doors and have the GENERAL appearance of the road car. Pratt & Miller welds a full tube cage to the rails, hangs a carbon fiber body, installs a Katech 7-liter (litre) engine that has a GM produced block (external dimensions the same size as the street LS1/6) and adds all the other race pieces. (Oh yeah, the tail lights are stock - one US spec and one Euro spec per side.)

Here is a pic I took at P & M in fall 2001 of C5R-006 and C5R-007 under construction (C5R-011 is now under construction):


Incidentally, C5R-007 is the first customer C5-R. It is running in the BelCar Series. And Chip Miller (Corvettes at Carlisle) just bought the Earnhardt car - C5R-004.

More details on all this can be found on my web site:
Corvette C5-R Information

[pgtr]

THanks. That photo shows the hydroformed frame rail too.

Why did they go w/ yellow currently in ALMS? I remember the silver/black from before. The yellow is a pretty color and very identifiable but why? Is it something to do w/ the sponsor (Compuware?) Whatever happened to the dark blue I saw a picture of once?

thanks again,

Oh I see you too have rediscovered slot cars!

[David]

Glad to help. The initial 1999 silver and black scheme tied in with their Goodwrench sponsorship. The Millennium Yellow was a new production color for 2000 and I speculate that GM marketing liked it for the new image and for better visibility on the track and on the telly.

The Le Mans Blue is new color for 2004 available only on "Commemorative Edition" production cars that have "Two Time Le Mans GTS Winner" badging. It was applied to the race cars at Le Mans only this year.:


Love the slot cars! I got back into it because they had the widest range of C5-R models and I am just now finishing a permanent 2-lane track. Now if I can figure out how to outrun my 9-year-old grandson!

[Chevyguy]

The Vettes were immediately repainted yellow after Le Mans because of traffic issues. Prototypes were making moves where they normally wouldn't have, and GTs didn't know the faster Vettes were coming up on them. That's why it seems like they have a forcefield through traffic, everyone knows which car is coming up on them. The blue paint scheme was refreshing, but it was a curse that I believe lost them the race.