14 replies to this topic

[mmcspecracer]

Congrats to the guys that were recently running 2:14s at VIR. I was just looking at a website called fastest laps and was astonished to see that the fastest time at VIR for a corvette ZR1 was 2:45. Ferrari 458 was 2:49. How could an SM be that much faster then these cars? What am i missing? Are the production cars running a longer course?

[Mike Collins]

The track was recently repaved and widened...A comparable SM time would be 2:18 for the old VIR full course...if you are looking at a magazine they may have used the Grand Course.

[jeopardyracing]

What Mike said - but it's an interesting question you ask. I don't have Corvette info, but back in 2011 I was a rookie running my third ever club race in an SSM Spec Miata. I had a friend who had a few track weekends under his belt running an E46 BMW M3. Pretty huge horsepower gap (333 for the BMW versus ....wait for it....101 for the SSM), but it turned out the two cars ran pretty similar lap times on the old VIR pavement (my best back then was 2:27s while his was 2:28s). In broad terms the difference between these very different cars and different drivers came down to the SSM being much slower on the straights, while being lots faster in the turns. Here are laps you can directly compare side by side (we thought it was fun to run them at the same time in two browser windows. Do it here one over the other after lining up the starting point. Watch what happens. The SSM is crushing the M3 until the back straight, here it weezes up to 100 mph or so while the M3 blasts to 120 and catches right back up!):

 

BMW M3 track day car, 2:28s:

 

 

SSM Spec Miata, 2:27s: 

 

 

BTW for comparison between the old pavement and wider track, newer pavement, here is a lap of the new track in the same SSM car from this past weekend. My weekend best was in the 2:23s (not sure this was the best lap) with some of those seconds attributable to the new pavement (2 seconds? 3 seconds?) and the balance being driver improvement (I've learned to push harder and use the curbing since 2011!)

 

SSM Spec Miata new pavement:

 

http://www.youtube.com/watch?v=fP32Ihe5wUo

 

So in summary, figure the Spec Miatas go slow as piss in the straights but faster in the turns to make up for their horsepower gap versus high horsepower street cars. The only way to compare the two for sure would be to have the same driver drive both on the same day, but I bet that is what you would find. That is, if you could find a race driver willing to push a ZR-1 at 10/10ths pace with three point street seatbelts and no cage!!

[JRHille]

At Mid-Ohio I drove a stock ZR-1 with lap times in the 1:35's on the same weekend with an SM in the 1:46's.   The magazine laps are usually on the grand course.  No replacement for displacement 'merica

[jeopardyracing]

Still that's only 10 seconds which is surprisingly small given the horsepower gap when you think about it.

[Alberto]

I have a few friends that do low 2 minute to 2:08s in their 3rd gen RX7 street/track cars.

 

I wouldn't drive a $100+k street in the same manner as I do the SM.  My wallet isn't that deep.

[jeopardyracing]

Excellent point Alberto. There is the [significant] safety issue of pushing these cars to their true limits without race gear, but there's also...that. Every now and then I have a track day friend venting frustration that they can't get their lap times down to race levels, and I have to remind them that getting all the way down necessarily will involve incidents, and that track days aren't the appropriate venue for true, 10/10ths running. That's all the more true for instructors who don't want to set a bad example.

 

So the hypothetical ZR-1 versus SM time trial winds up being kind of hard to test in a literal sense, interesting though I [for one] find it.

 

I can't imagine attaining VIR back straight top speed in a ZR-1 with street belts and no cage. In fact, that's why my friend in the videos above gave up track days. He realized the speeds in the M3 were getting totally out of hand and didn't want to gut and cage it to make it safer. Probably pretty good judgement. 

[Jeff Wasilko]

Be sure you're comparing the same track config at VIR. The grand east or west are a mile longer than 'full' which is the standard race config:http://en.wikipedia....#Configurations

[Alberto]

Excellent point Alberto. There is the [significant] safety issue of pushing these cars to their true limits without race gear, but there's also...that. Every now and then I have a track day friend venting frustration that they can't get their lap times down to race levels, and I have to remind them that getting all the way down necessarily will involve incidents, and that track days aren't the appropriate venue for true, 10/10ths running. That's all the more true for instructors who don't want to set a bad example.

 

So the hypothetical ZR-1 versus SM time trial winds up being kind of hard to test in a literal sense, interesting though I [for one] find it.

 

I can't imagine attaining VIR back straight top speed in a ZR-1 with street belts and no cage. In fact, that's why my friend in the videos above gave up track days. He realized the speeds in the M3 were getting totally out of hand and didn't want to gut and cage it to make it safer. Probably pretty good judgement. 

 

There's also the fact that race cars have stiffer chassis thanks to the roll cages and suspensions so the comparisons are not exactly apples to apples.

 

I hear you on the speeds.  At fast tracks like Bridgehampton, Watkins Glen, Buttonwillow and Thunderhill, I was hitting ludicrous speeds in my RX7 with nothing more than 3 point belts.  Very exciting but after watching less lucky people wreck at speed at events over the years I decided a caged race car and safety equipment were a better and cheaper approach.  Even a short, slower track like Lime Rock could get interesting on the main straight going into Big Bend.

 

I'm sure most of the people here can relate.

[Jim Boemler]

I can't speak to VIR, but I've driven my SM and Z06 on the same track on sequential similar days.  The SM was in the 1:44's, the Z06 (bone stock) in the 1:35's.  The Corvette had several seconds left on the table, even with me driving it; with a more experienced high-HP driver it could do even better.  No, the SM is no match for a Corvette on anything more open than an autocross course.  BTW, the Corvette didn't give up much on the corners either.  Great track car.

[jeopardyracing]

Interesting! So that's two data points were a 'Vette driven perhaps 8.5 or 9/10ths is 10 seconds quicker. Would be interesting to see how 10/10ths would compare but this is actually perfectly good real world data, since as discussed 10/10ths would be inadvisable. Interesting!

[mmcspecracer]

Just checked and Car and Driver runs the 4.1 mile configuration. So thanks for confirming that they are running a longer course. Still very interesting to see all the members that have run high horsepower cars back to back against their spec miata. I think its a lot more fun running a lower horsepower car at 10/10ths then a high horsepower car at 7/10 ths. No better feeling then when you have the slip angle perfect.

[Jim Boemler]

I wouldn't say I was going at 7/10ths.  In fact in my last track session in the Z06 I made a fairly minor mistake (or at least it would have been minor in the SM...), and put the car into a dirt embankment at fairly high speed.  Turn 1 at this track is a barely perceptible bend at 120 mph in the SM; at over 150 in the Z06 it gets your attention.  You're right about the great feeling, but it's even better at higher speed.

[zoomzoom22]

I have a few friends that do low 2 minute to 2:08s in their 3rd gen RX7 street/track cars.
 
I wouldn't drive a $100+k street in the same manner as I do the SM.  My wallet isn't that deep.

T3 cars were in the high 2:08's last year before the repave
T4 track record was 217.0 before repave

And M3 doing 2:28's would be an ITC time I think

T1 track record was faster than that ZR-1 time at Mid-Ohio and that was club course....

Funny math in some of these posts. Track records for VIR are on the NC SPCA website and I doubt have been updated post repave yet.

[JRHille]

T3 cars were in the high 2:08's last year before the repave
T4 track record was 217.0 before repave

And M3 doing 2:28's would be an ITC time I think

T1 track record was faster than that ZR-1 time at Mid-Ohio and that was club course....

Funny math in some of these posts. Track records for VIR are on the NC SPCA website and I doubt have been updated post repave yet.

We were on the club course as well.  Not that any of this has any value to me  

 

No possible way to compare two totally different cars.  They're both fun in their own ways.  I like that, with the miata, it's relatively easy to know you're getting very close to 100% out of the car. There is something very fun and satisfying about that.