how would our 04 thru 07 V's in stock form do against RX-8's on a auto-x course?
#21
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You're right in that the other driver may well have been better. However, it's the best real-world example with objective numbers in an autocross environment I have. If you have better numbers taken from cars that are actually modified for SCCA autocrossing, please post them. And if the numbers you posted don't have the two cars on the same tire then it's not a valid comparison anyway.
Let's examine how the cars compare to each other when modified for SCCA autocrossing. Let's compare a B-stock RX8 vs. an F-stock CTS-V. Stock class rules say that you can use aftermarket wheels so long as they're the stock size. Both the RX8 and CTS-V have 18x8 wheels, but the Mazda has a much greater selection of lighter-weight wheels than the CTS-V does. So the Mazda will drop more rotating, unsprung mass than the Caddy will.
Tires: In stock class any tire that will fit on the stock-size wheel is legal. Stock class guys get pretty crazy here, so 295s on 8-inch wheels are common. The RX8 can fit 295s on all four corners; the CTS-V can't get 295s up front, at least not while complying with the rules. And since the RX8 rolls on 225s stock vs the V on 245s, the RX8 will gain 70mm per tire while the Caddy will only get 50mm extra in back and maybe 20mm extra in front. That's an advantage for the Mazda.
I also think you underestimate the advantages that the RX8's shorter wheelbase and shorter overall length give it on a tight autocross course.
This thread (http://www.rx8club.com/showthread.php?t=133564) has a list of BS-class weights at the 2007 SCCA Solo Nationals. The RX8s are all right around 2800 pounds; the lightest RX8 on the list is 2792 pounds. My 05 CTS-V w/sunroof was 3,802. Take a non-sunroof car and use legal tricks like a lighter battery, custom lightweight catback (the Corsa is 7 pounds heavier than stock), race tires and (custom, probably not available) lightweight 18x8s and maybe you could drop the V to maybe 3,650--MAYBE. But how can you expect the CTS-V to compete with a car that's 850-1,000 pounds lighter but rolling on the same size tires?
If you seriously think that a CTS-V will beat an RX8 when both cars are prepared to the limits of the rules then try it. Here's the 2010 SCCA National Tour schedule:
http://scca.org/contentpage.aspx?content=56
Let's examine how the cars compare to each other when modified for SCCA autocrossing. Let's compare a B-stock RX8 vs. an F-stock CTS-V. Stock class rules say that you can use aftermarket wheels so long as they're the stock size. Both the RX8 and CTS-V have 18x8 wheels, but the Mazda has a much greater selection of lighter-weight wheels than the CTS-V does. So the Mazda will drop more rotating, unsprung mass than the Caddy will.
Tires: In stock class any tire that will fit on the stock-size wheel is legal. Stock class guys get pretty crazy here, so 295s on 8-inch wheels are common. The RX8 can fit 295s on all four corners; the CTS-V can't get 295s up front, at least not while complying with the rules. And since the RX8 rolls on 225s stock vs the V on 245s, the RX8 will gain 70mm per tire while the Caddy will only get 50mm extra in back and maybe 20mm extra in front. That's an advantage for the Mazda.
I also think you underestimate the advantages that the RX8's shorter wheelbase and shorter overall length give it on a tight autocross course.
This thread (http://www.rx8club.com/showthread.php?t=133564) has a list of BS-class weights at the 2007 SCCA Solo Nationals. The RX8s are all right around 2800 pounds; the lightest RX8 on the list is 2792 pounds. My 05 CTS-V w/sunroof was 3,802. Take a non-sunroof car and use legal tricks like a lighter battery, custom lightweight catback (the Corsa is 7 pounds heavier than stock), race tires and (custom, probably not available) lightweight 18x8s and maybe you could drop the V to maybe 3,650--MAYBE. But how can you expect the CTS-V to compete with a car that's 850-1,000 pounds lighter but rolling on the same size tires?
If you seriously think that a CTS-V will beat an RX8 when both cars are prepared to the limits of the rules then try it. Here's the 2010 SCCA National Tour schedule:
http://scca.org/contentpage.aspx?content=56
#22
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We are down to comparing cars here. Your times vs. the RX8 times in that event don't bear much significance. Put the same driver in both cars stock/stock and then we will know for certain. While I am sure you are a good driver, the RX8 driver could be that much better and that much more familiar with his car if he has been campaigning it for longer.
Most people that run in SCCA are not going to buy a Cadillac to go out and beat the hell out of it at an auto-x event. They are also not going to buy a Cadillac and make it a pure auto-x car which is what I am betting most of the miata's and RX8's are. Most owners are going to drive the V to the event, have some fun on the course and drive home. As for the RX8 and Miata's, I am sure the owners have no problem beating the ever loving crap out of them.
The slalom of the V and RX8 are very close. While the RX8 will definitely switchback slightly faster its not that far superior to the V, and what the V loses in the slalom it will more than pick up in the acceleration times which is also very important in the smaller auto-x events.
Most people that run in SCCA are not going to buy a Cadillac to go out and beat the hell out of it at an auto-x event. They are also not going to buy a Cadillac and make it a pure auto-x car which is what I am betting most of the miata's and RX8's are. Most owners are going to drive the V to the event, have some fun on the course and drive home. As for the RX8 and Miata's, I am sure the owners have no problem beating the ever loving crap out of them.
The slalom of the V and RX8 are very close. While the RX8 will definitely switchback slightly faster its not that far superior to the V, and what the V loses in the slalom it will more than pick up in the acceleration times which is also very important in the smaller auto-x events.
i have driven the doors off a rx-8 at an autox. i just dont see how a v would have done as well. its like a bull in a china shop on those really small autox courses. even sports cars like c5's/c6's were putting up worst times then the rx-8 did.
the slalom and braking is the key when it comes to something like this. the v might get the the first turn faster... but normally thats the only flat out section, the rx-8 would walk away from that point.
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Thank you for your input. No I am not kidding. I have driven both cars and feel that with myself at the wheel the CTS-V would be faster then the RX8 ten times out of ten. Now I am not saying I'm the best driver out there, but the best comparison would be driving against yourself right?
Thank goodness my V goes more than 111' without breaking! That would sure make my daily commute a grind!!
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We are down to comparing cars here. Your times vs. the RX8 times in that event don't bear much significance. Put the same driver in both cars stock/stock and then we will know for certain. While I am sure you are a good driver, the RX8 driver could be that much better and that much more familiar with his car if he has been campaigning it for longer.
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Except it's not.
Anyway, I'm sure I'm wasting my breath. This thread has evolved exactly as I figured it would even before I opened it.
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I also agree that a super small course is a different story. I have been to many auto-x events and the ones that I went to you could reach speeds in excess of 75 mph on some of the straights. These weren't SCCA sanctioned races but it was still auto-x.
Comparing the typical 700ft slalom that magazines do (100ft cone spacing) to a typical auto-x slalom isn't particularly useful. Even on R-compounds in my light(er), nimble, auto-x prepped Subaru there are very few auto-x slaloms that I can navigate at 67mph. A shorter slalom (think 45-65ft cone spacing) means the transitions are that much faster and makes the extra 800+lb that much more of a weakness.
That's true at the local level. Again, comparing results at the local level just doesn't mean much. The top level national drivers find the platform that works the best and develop it. Sam Strano auto-x'd F-bodys Camaros for years, winning a few Solo National and ProSolo National titles, then jumped ship in just the past couple/few years to the S197 Mustangs. He (and all the other top level FS drivers) would buy a CTS-V (rather than spending more on a new Mustang) if it were the car to beat in the class, but it just isn't.
Just look at the SCCA classing - the RX-8 is in B Stock, the CTS-V is in F Stock. B Stock is a faster class than F Stock. At Nationals last year the top BS time was 4sec (over 2 days) faster than FS - 117sec vs 121sec. Add in the fact that the RX-8 is the car to beat in BS (14 of the top 15 cars in BS @ the 2009 Nationals were RX-8s), and has been for a couple of years now, while the CTS-V isn't even competitive in FS (not a single one in the 26 car class at Nationals).
Also, how much faster was the top B-Stock time over the top D-stock time?
So acceleration isn't important in auto-x? Ok.
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Now... Be sure to read this part. I am NOT saying the V will beat the RX8. I am saying it should be competitive and it will DEFINITELY not get destroyed.
Last edited by 2003RC51; 01-18-2010 at 03:50 PM.
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I think you are placing to much faith in how they place the cars in those classes. Sure, most of them are correct but the CTS-V being placed in F-Stock while the base CTS is placed in D-stock??? I guess that means the base CTS is faster than the V since its in a higher class? I think not.
At the NT I raced the Caddy at, the stock class winners, from fastest to slowest, went like this: SS (Lotus Elise), FS (Shelby GT), AS (S2000), ES (Celica), BS (RX8), CS (Miata), DS (ITR), GS (Mini), HS (Civic).
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DS is not necessarily a faster class than FS; cars aren't automatically classed by speed alone. DS is a class for fast FWD cars with good diffs (ITR, Cobalt SS, Mini Cooper S) and a few oddball RWD cars (some BMWs, Crossfire). FS is for pony cars and other large-ish RWD vehicles (G35, etc.).
At the NT I raced the Caddy at, the stock class winners, from fastest to slowest, went like this: SS (Lotus Elise), FS (Shelby GT), AS (S2000), ES (Celica), BS (RX8), CS (Miata), DS (ITR), GS (Mini), HS (Civic).
At the NT I raced the Caddy at, the stock class winners, from fastest to slowest, went like this: SS (Lotus Elise), FS (Shelby GT), AS (S2000), ES (Celica), BS (RX8), CS (Miata), DS (ITR), GS (Mini), HS (Civic).
#28
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Are there people here that just argue for the sake of arguing? Oh, right, a car forum. Of COURSE!
I had my '05 RX8 down to 2810 lbs. Weight trumps all at an autox. While the absolute numbers of the RX8 are misleading, this is one of them 'magic cars' that the sum of the parts are greater than the whole. The 8 does auto-x fantastically. The V? Not so much.
There's this little thing called momentum that is talked about very little. Being able to keep the speed your at though a turn. All things being equal (specifically stock class rules and same national caliber driver doing back to back runs), other than the obvious weight penalty for the V, the 8 will be able to keep a higher average speed through most auto-x maneuvers than a V because it can keep its momentum from not having much weight (and conversely much less scrubbing of speed) though the turns.
It's "light in the loafers". While power and torque are wonderful things for coming out of corners and straights, getting INTO the corner and settling the car before turn in is where the V loses. While they more than likely have the same published numbers for *straight line braking* there are very few chances on your typical auto-x course to actually brake in a straight line. Most auto-x braking is trail braking, doing the minimum amount of braking to get the car to turn in... in other words, keeping your speed aka. momentum through a turn.
A car that's 800 lbs lighter, but on the same tires, will be able to keep a higher rate of speed through a turn. It's simple physics... with the same amount of grip available, but at a higher weight, the V will have to give up more speed entering the turn because that weight will want to continue to go straight *more than* the RX8 will if it *didn't* give up more.
That's just the way it works. Auto-x is a different sport where weight + grip > power. There are no straights to open up any car.... it's all about momentum and losing as little momentum as possible. The V is not a car known for changing directions (aka transition) quickly.
I can understand how you guys love your cars. They're just phenomenal sedans. Having been in quite a few, I wouldn't turn one down. But realistically, they don't have a snowballs chance in hell against an RX8 given same drivers in stock class. The RX8 has the same grip, but *much* lower weight.
--kC
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Are there people here that just argue for the sake of arguing? Oh, right, a car forum. Of COURSE!
I had my '05 RX8 down to 2810 lbs. Weight trumps all at an autox. While the absolute numbers of the RX8 are misleading, this is one of them 'magic cars' that the sum of the parts are greater than the whole. The 8 does auto-x fantastically. The V? Not so much.
There's this little thing called momentum that is talked about very little. Being able to keep the speed your at though a turn. All things being equal (specifically stock class rules and same national caliber driver doing back to back runs), other than the obvious weight penalty for the V, the 8 will be able to keep a higher average speed through most auto-x maneuvers than a V because it can keep its momentum from not having much weight (and conversely much less scrubbing of speed) though the turns.
It's "light in the loafers". While power and torque are wonderful things for coming out of corners and straights, getting INTO the corner and settling the car before turn in is where the V loses. While they more than likely have the same published numbers for *straight line braking* there are very few chances on your typical auto-x course to actually brake in a straight line. Most auto-x braking is trail braking, doing the minimum amount of braking to get the car to turn in... in other words, keeping your speed aka. momentum through a turn.
A car that's 800 lbs lighter, but on the same tires, will be able to keep a higher rate of speed through a turn. It's simple physics... with the same amount of grip available, but at a higher weight, the V will have to give up more speed entering the turn because that weight will want to continue to go straight *more than* the RX8 will if it *didn't* give up more.
That's just the way it works. Auto-x is a different sport where weight + grip > power. There are no straights to open up any car.... it's all about momentum and losing as little momentum as possible. The V is not a car known for changing directions (aka transition) quickly.
I can understand how you guys love your cars. They're just phenomenal sedans. Having been in quite a few, I wouldn't turn one down. But realistically, they don't have a snowballs chance in hell against an RX8 given same drivers in stock class. The RX8 has the same grip, but *much* lower weight.
--kC
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--kC