[ANSWERED] Z06 @ MT's BDC
10-15-2015, 03:55 PM
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[ANSWERED] Z06 @ MT's BDC
Original question is here.
four0nefive asked:
I think many people want an answer to this question. I'm not sure if you are aware, but the Z06 that was supplied to Motor Trend for their Best Drivers Car competition finished as a DNF (last place). They noted that the car was supplied with worn brake pads and that the supercharger refused to make boost. We would like to know whether these press cars are checked to make sure if they are in proper condition before they are sent out? It seems like they haven't been checked considering that this is the 2nd time a car was sent to MT and didn't perform properly. To add to this, is it possible that Jim or someone from the racing team will do a hot lap at Laguna Seca since MT will most likely not retest the Z06 at LS?
I think many people want an answer to this question. I'm not sure if you are aware, but the Z06 that was supplied to Motor Trend for their Best Drivers Car competition finished as a DNF (last place). They noted that the car was supplied with worn brake pads and that the supercharger refused to make boost. We would like to know whether these press cars are checked to make sure if they are in proper condition before they are sent out? It seems like they haven't been checked considering that this is the 2nd time a car was sent to MT and didn't perform properly. To add to this, is it possible that Jim or someone from the racing team will do a hot lap at Laguna Seca since MT will most likely not retest the Z06 at LS?
Tadge answered:
The short answer to this question is, yes, we check our press cars before we send them out. However, you are probably looking for the full story and how to reconcile how a Z06, actually the exact same Z06, could do so well in Car and Driver's hands for the Lightning Lap and be such a disappointment weeks later in Motor Trend's Best Driver's car issue.
First a little background: Corvettes are highly sought after test cars for media around the world. The number of requests we get to evaluate cars is well beyond our ability to accommodate them. We have to pick and choose and set priorities. The natural question might be: "You are the manufacturer. Why don't you just make more cars and have a bigger press fleet?" The truth is we have limited resources to manage such fleets and since we are capacity-constrained in production at Bowling Green, every car we put into the press fleet is a car we take away from a paying customer. That means people who have had orders placed for a long time have to wait even longer. We try to accommodate as many media requests as we can and that means there is enormous pressure to minimize the prep time for cars between media loans. Media deadlines are absolute, just like race start times, if you aren't ready when the green flag drops, you don't run. The goal for media prep is always the same: Make the car like-new for each loan. Sometimes this is easy, sometimes there is a lot of work to be done. Magazines and other media rightly expect the cars to be perfect, both mechanically and aesthetically. They usually use the same car for photography and track testing. It would be great to send two cars for every loan, so we would have a back-up, but then we would have to double the size of our fleet (see above). Bottom line is that the Car and Driver loan and Motor Trend loan were scheduled back to back. What could go wrong, right?
A lot, as it turns out. During testing at C and D the car went off track into a tire wall. Stuff happens. It wasn't the first time this has happened and I'm certain it won't be the last. Fortunately, the damage to the car was cosmetic (rear fascia, supports and the energy absorption assembly). It didn't have any fundamental structural or chassis damage. The alignment was fine. Basically, zip ties and some duct tape was all it took to make it track-worthy. The car then went out and ran the second fastest Lightening Lap they have ever recorded.
Any time there is an incident like that, we have to tear the car down, replace broken parts and make it like-new again. In the few days we had to prep the car for Motor Trend, we did a tremendous amount of work to make sure the car was safe, capable and pretty. In our haste, two things were missed. We always replace brake pads before delivering a car, but this was missed. I can’t remember this ever happening before, but it did. We have since changed our pre-test check procedure so this can never happen again. Although Motor Trend made it a point in the article, they did not notice any issue with braking performance during their spirited street drives. Our engineer on-site noticed the linings were worn, and they were immediately replaced and burnished. This was done the day before the Z06 was run on track by Randy Pobst and had absolutely no bearing on the results of the test.
The second unfortunate occurrence related to the intercooler circuit. One of our pre-loan checks is to bleed the intercooler circuit to make sure there is no air in it. Some customer complaints about over heating Z06s have been traced to improperly bled intercoolers. The technician doing the work plugged in the electrical connector for the intercooler pump and it seemed to seat and "click" into position, but the secondary latching mechanism did not fully lock into position leading to intermittent operation. Without the pump running there is no coolant flow, no intake charge cooling and the engine pulls spark to protect itself. That is what Motor Trend experienced at random times during their testing. Unfortunately, the connector was seated enough that the pump and engine worked fine in all the pre-test driving done before trucking the car across the country to Motor Trend in California. Remember this is the same car that performed flawlessly a few weeks prior in sweltering heat during Car and Driver's Lightning Lap. The possibility of bad fuel was discussed because it was clear there was an abundant amount of spark retard, but we didn't discover the true root cause until the car had returned to the Milford Proving Grounds after the test. We have modified our procedure to run the pump remotely during the bleed process so this issue can be avoided in the future.
Bottom line is that like any team we have good days and we have bad days. We showed well at Car and Driver Lightning Lap and stumbled at Motor Trend. We engineers and technicians on the team are even more disappointed than any in the Corvette community. We are reviewing our prep processes, which loans we prioritize and even the size of our media fleet. We will get better. We will live to fight another day. Motor Trend is planning another test at Laguna Seca in a few months with some very, very capable competitors. We intend to be ready.
The short answer to this question is, yes, we check our press cars before we send them out. However, you are probably looking for the full story and how to reconcile how a Z06, actually the exact same Z06, could do so well in Car and Driver's hands for the Lightning Lap and be such a disappointment weeks later in Motor Trend's Best Driver's car issue.
First a little background: Corvettes are highly sought after test cars for media around the world. The number of requests we get to evaluate cars is well beyond our ability to accommodate them. We have to pick and choose and set priorities. The natural question might be: "You are the manufacturer. Why don't you just make more cars and have a bigger press fleet?" The truth is we have limited resources to manage such fleets and since we are capacity-constrained in production at Bowling Green, every car we put into the press fleet is a car we take away from a paying customer. That means people who have had orders placed for a long time have to wait even longer. We try to accommodate as many media requests as we can and that means there is enormous pressure to minimize the prep time for cars between media loans. Media deadlines are absolute, just like race start times, if you aren't ready when the green flag drops, you don't run. The goal for media prep is always the same: Make the car like-new for each loan. Sometimes this is easy, sometimes there is a lot of work to be done. Magazines and other media rightly expect the cars to be perfect, both mechanically and aesthetically. They usually use the same car for photography and track testing. It would be great to send two cars for every loan, so we would have a back-up, but then we would have to double the size of our fleet (see above). Bottom line is that the Car and Driver loan and Motor Trend loan were scheduled back to back. What could go wrong, right?
A lot, as it turns out. During testing at C and D the car went off track into a tire wall. Stuff happens. It wasn't the first time this has happened and I'm certain it won't be the last. Fortunately, the damage to the car was cosmetic (rear fascia, supports and the energy absorption assembly). It didn't have any fundamental structural or chassis damage. The alignment was fine. Basically, zip ties and some duct tape was all it took to make it track-worthy. The car then went out and ran the second fastest Lightening Lap they have ever recorded.
Any time there is an incident like that, we have to tear the car down, replace broken parts and make it like-new again. In the few days we had to prep the car for Motor Trend, we did a tremendous amount of work to make sure the car was safe, capable and pretty. In our haste, two things were missed. We always replace brake pads before delivering a car, but this was missed. I can’t remember this ever happening before, but it did. We have since changed our pre-test check procedure so this can never happen again. Although Motor Trend made it a point in the article, they did not notice any issue with braking performance during their spirited street drives. Our engineer on-site noticed the linings were worn, and they were immediately replaced and burnished. This was done the day before the Z06 was run on track by Randy Pobst and had absolutely no bearing on the results of the test.
The second unfortunate occurrence related to the intercooler circuit. One of our pre-loan checks is to bleed the intercooler circuit to make sure there is no air in it. Some customer complaints about over heating Z06s have been traced to improperly bled intercoolers. The technician doing the work plugged in the electrical connector for the intercooler pump and it seemed to seat and "click" into position, but the secondary latching mechanism did not fully lock into position leading to intermittent operation. Without the pump running there is no coolant flow, no intake charge cooling and the engine pulls spark to protect itself. That is what Motor Trend experienced at random times during their testing. Unfortunately, the connector was seated enough that the pump and engine worked fine in all the pre-test driving done before trucking the car across the country to Motor Trend in California. Remember this is the same car that performed flawlessly a few weeks prior in sweltering heat during Car and Driver's Lightning Lap. The possibility of bad fuel was discussed because it was clear there was an abundant amount of spark retard, but we didn't discover the true root cause until the car had returned to the Milford Proving Grounds after the test. We have modified our procedure to run the pump remotely during the bleed process so this issue can be avoided in the future.
Bottom line is that like any team we have good days and we have bad days. We showed well at Car and Driver Lightning Lap and stumbled at Motor Trend. We engineers and technicians on the team are even more disappointed than any in the Corvette community. We are reviewing our prep processes, which loans we prioritize and even the size of our media fleet. We will get better. We will live to fight another day. Motor Trend is planning another test at Laguna Seca in a few months with some very, very capable competitors. We intend to be ready.
10-15-2015, 06:31 PM
#2
As they say, "**** happens". And intermittent connector faults are always really hard to find, so it was just bad luck it seems. Looking forward to the next Laguna test with those very, very capable competitors.
Unfortunately while the car ran fine in the "sweltering heat" at VIR, that does not help that my Z51 M7 MRC fails by destroying the AFM actuators every single time I have taken it to the track, the transmission temperature gauge gets pinned at 300 F every session and takes forever to come back down, and even in sub 86 degree weather I get an ever rising coolant temperature gauge and often get an "Engine Overheat - Idle Engine" message on the dash while barreling down the straight". I wish GM would fix that, as it has been 1.5 years now and zero solutions have been offered. Still waiting for their buyback offer they have told me is coming, and perhaps a move to a Z06 as an upgrade. This MT test and other reports here and in the press are really making me hesitate regarding a Z06, as my Z51 has consistent overheating issues on track, so will a Z06 be the same for me? That MT test result makes me want to look at an AMG GT-S instead. That is the effect of these magazine tests, some people like to go for the winner. Z06 did not impress, even if it was just a loose connector. Not into a single hot lap either, I want a car that can run all day long for 30 minutes on, 30 minutes off, flat out.
Unfortunately while the car ran fine in the "sweltering heat" at VIR, that does not help that my Z51 M7 MRC fails by destroying the AFM actuators every single time I have taken it to the track, the transmission temperature gauge gets pinned at 300 F every session and takes forever to come back down, and even in sub 86 degree weather I get an ever rising coolant temperature gauge and often get an "Engine Overheat - Idle Engine" message on the dash while barreling down the straight". I wish GM would fix that, as it has been 1.5 years now and zero solutions have been offered. Still waiting for their buyback offer they have told me is coming, and perhaps a move to a Z06 as an upgrade. This MT test and other reports here and in the press are really making me hesitate regarding a Z06, as my Z51 has consistent overheating issues on track, so will a Z06 be the same for me? That MT test result makes me want to look at an AMG GT-S instead. That is the effect of these magazine tests, some people like to go for the winner. Z06 did not impress, even if it was just a loose connector. Not into a single hot lap either, I want a car that can run all day long for 30 minutes on, 30 minutes off, flat out.
10-15-2015, 07:37 PM
#3
Instructor
Why did they claim that GM engineers were blaming the 91 octane then? the article states that the switch from 91 to 101 octane confused the ecu and caused the issues.
10-15-2015, 07:48 PM
#4
What do you, the patient, say to the Doctor that messed up your Surgery after he has had a bad day? Ahhhh Fuhgettaboutit Doc. " **** happens?"
What do you say to the pilot.....?
Or Air traffic controller?
Still not hearing the F word. ,
What do you say to the pilot.....?
Or Air traffic controller?
Still not hearing the F word. ,
10-15-2015, 07:53 PM
#5
Bad luck but happy to know the Z06 will be retested soon at Laguna Seca by MT. Randy was happy with the handling / cornering of the Z06 and braking. It was loosing on the straight line and we all know the Z06 doesn't have a problem with straight line speed. I think it will do very well on the next test.
10-15-2015, 08:10 PM
#6
Bad luck but happy to know the Z06 will be retested soon at Laguna Seca by MT. Randy was happy with the handling / cornering of the Z06 and braking. It was loosing on the straight line and we all know the Z06 doesn't have a problem with straight line speed. I think it will do very well on the next test.
10-15-2015, 08:49 PM
#7
Safety Car
"One of our pre-loan checks is to bleed the intercooler circuit to make sure there is no air in it. Some customer complaints about over heating Z06s have been traced to improperly bled intercoolers."
I see what Tadge did here. OK. I suppose I should take the car in to have the intercooler checked everytime the car overheats. I'm OK with that.
Is this a service bulletin item yet?
I see what Tadge did here. OK. I suppose I should take the car in to have the intercooler checked everytime the car overheats. I'm OK with that.
Is this a service bulletin item yet?
10-15-2015, 08:57 PM
#8
Corvette Enthusiast
We will live to fight another day. Motor Trend is planning another test at Laguna Seca in a few months with some very, very capable competitors. We intend to be ready.
10-15-2015, 09:35 PM
#9
Melting Slicks
Thank you Tadge for answering the question (if he reads the forums). I'm glad that he owned up to the mistake instead of making something up. Can't wait to see the restest @ LS. I'm guessing they'll have a GT3 RS, ACR, and maybe something else. Should be good either way.
10-15-2015, 09:36 PM
#10
Melting Slicks
As they say, "**** happens". And intermittent connector faults are always really hard to find, so it was just bad luck it seems. Looking forward to the next Laguna test with those very, very capable competitors.
Unfortunately while the car ran fine in the "sweltering heat" at VIR, that does not help that my Z51 M7 MRC fails by destroying the AFM actuators every single time I have taken it to the track, the transmission temperature gauge gets pinned at 300 F every session and takes forever to come back down, and even in sub 86 degree weather I get an ever rising coolant temperature gauge and often get an "Engine Overheat - Idle Engine" message on the dash while barreling down the straight". I wish GM would fix that, as it has been 1.5 years now and zero solutions have been offered. Still waiting for their buyback offer they have told me is coming, and perhaps a move to a Z06 as an upgrade. This MT test and other reports here and in the press are really making me hesitate regarding a Z06, as my Z51 has consistent overheating issues on track, so will a Z06 be the same for me? That MT test result makes me want to look at an AMG GT-S instead. That is the effect of these magazine tests, some people like to go for the winner. Z06 did not impress, even if it was just a loose connector. Not into a single hot lap either, I want a car that can run all day long for 30 minutes on, 30 minutes off, flat out.
Unfortunately while the car ran fine in the "sweltering heat" at VIR, that does not help that my Z51 M7 MRC fails by destroying the AFM actuators every single time I have taken it to the track, the transmission temperature gauge gets pinned at 300 F every session and takes forever to come back down, and even in sub 86 degree weather I get an ever rising coolant temperature gauge and often get an "Engine Overheat - Idle Engine" message on the dash while barreling down the straight". I wish GM would fix that, as it has been 1.5 years now and zero solutions have been offered. Still waiting for their buyback offer they have told me is coming, and perhaps a move to a Z06 as an upgrade. This MT test and other reports here and in the press are really making me hesitate regarding a Z06, as my Z51 has consistent overheating issues on track, so will a Z06 be the same for me? That MT test result makes me want to look at an AMG GT-S instead. That is the effect of these magazine tests, some people like to go for the winner. Z06 did not impress, even if it was just a loose connector. Not into a single hot lap either, I want a car that can run all day long for 30 minutes on, 30 minutes off, flat out.
10-15-2015, 09:47 PM
#11
Thank you Tadge for answering the question (if he reads the forums). I'm glad that he owned up to the mistake instead of making something up. Can't wait to see the restest @ LS. I'm guessing they'll have a GT3 RS, ACR, and maybe something else. Should be good either way.
Or maybe the 488 wow that should be a good one.
10-15-2015, 10:09 PM
#13
Drifting
I'm having a hard time swallowing why GM cannot pony up at least 2 more cars for all "loans". I'm hearing the reason that it's cost prohibitive...really.
I've got to think that all the bad press and lost revenue due to these issues has got to be more cost prohibitive.
Seems very short sighted if you ask me. VERY short sighted!!!
415-why are you giving crap to a guy who has shelled out a fair amount of $ and his car issues have not been solved by GM. Heck, I'd look for every chance to bring it up in a public forum where maybe someone sees it and takes it seriously. When you get a little more time behind the wheel of life, I think you'd see it differently!
I've got to think that all the bad press and lost revenue due to these issues has got to be more cost prohibitive.
Seems very short sighted if you ask me. VERY short sighted!!!
415-why are you giving crap to a guy who has shelled out a fair amount of $ and his car issues have not been solved by GM. Heck, I'd look for every chance to bring it up in a public forum where maybe someone sees it and takes it seriously. When you get a little more time behind the wheel of life, I think you'd see it differently!
Last edited by dbs1vette; 10-15-2015 at 10:14 PM.
10-15-2015, 10:24 PM
#14
Drifting
I'm having a hard time swallowing why GM cannot pony up at least 2 more cars for all "loans". I'm hearing the reason that it's cost prohibitive...really.
I've got to think that all the bad press and lost revenue due to these issues has got to be more cost prohibitive.
Seems very short sighted if you ask me. VERY short sighted!!!
I've got to think that all the bad press and lost revenue due to these issues has got to be more cost prohibitive.
Seems very short sighted if you ask me. VERY short sighted!!!
He SPECIFICALLY said they were considering adding cars....
"which loans we prioritize and even the size of our media fleet."
With that said, this is a perfectly logical and greatly appreciated. Now I have an answer when people ask me about it. Plus, GM is implementing some changes in their processes. This is good news all around.
10-16-2015, 12:13 AM
#16
Le Mans Master
Well, you aren't good at your job if you can't perform proper damage control.
If I step back and don't read the words in specifics, what it all breaks down to is a bunch of excuses. I've had employees stand in front of me with half the excuses just given and that was their last day.
I empathize with the difficulty bestowed on the Corvette team, but let's be honest, this comes down to mismanagement...at some level...and it appears on many levels.
All I just read is a bunch of bean counter bs. Team not big enough, not enough test cars, inadequate prep, overlooking important details, etc. If this is the mismanagement that is visible, imagine what we don't see.
If I step back and don't read the words in specifics, what it all breaks down to is a bunch of excuses. I've had employees stand in front of me with half the excuses just given and that was their last day.
I empathize with the difficulty bestowed on the Corvette team, but let's be honest, this comes down to mismanagement...at some level...and it appears on many levels.
All I just read is a bunch of bean counter bs. Team not big enough, not enough test cars, inadequate prep, overlooking important details, etc. If this is the mismanagement that is visible, imagine what we don't see.
10-16-2015, 05:35 AM
#17
10-16-2015, 06:56 AM
#18
Well, you aren't good at your job if you can't perform proper damage control.
If I step back and don't read the words in specifics, what it all breaks down to is a bunch of excuses. I've had employees stand in front of me with half the excuses just given and that was their last day.
I empathize with the difficulty bestowed on the Corvette team, but let's be honest, this comes down to mismanagement...at some level...and it appears on many levels.
All I just read is a bunch of bean counter bs. Team not big enough, not enough test cars, inadequate prep, overlooking important details, etc. If this is the mismanagement that is visible, imagine what we don't see.
If I step back and don't read the words in specifics, what it all breaks down to is a bunch of excuses. I've had employees stand in front of me with half the excuses just given and that was their last day.
I empathize with the difficulty bestowed on the Corvette team, but let's be honest, this comes down to mismanagement...at some level...and it appears on many levels.
All I just read is a bunch of bean counter bs. Team not big enough, not enough test cars, inadequate prep, overlooking important details, etc. If this is the mismanagement that is visible, imagine what we don't see.
Firing the guy that knows exactly what happened and why rather than letting the team learn from mistakes, correct procedures and expenditures and move on to better things would be among the WORST forms of mismanagement there is.
If you really do fire people for letting you know what went wrong, you have a LOT to learn about team building.
What I really read here is while the car had prep issues, they were more the result of lack of available time to do the job at hand because of the amount of work needed between the events. Lots of blame to go around. This was a team screw up. Not the guy that plugged in the intercooler.
What is evident is that the engineers on site do not have sufficient background with this cars control systems to know how to diagnose it. As soon as I read the article I thought to myself it was an intercooler loop problem. Been there and done that, my Ford GT suffered the same exact malady once. Unfortunately mine was a pump failure.
Thank you Tadge for the straightforward answer. Now we at least know what went wrong. Please do not let this happen again.
10-16-2015, 07:34 AM
#19
I appreciate that we got "the long story" rather than just "We screwed up, sorry" with no specifics. While it is unfortunate that escapes happened on such a high profile test, it is good to hear that they have revised/improved process to prevent these/similar failures again, and are re-evaluating their test fleet size. As someone who works for a large engineering firm, I can certainly appreciate the struggle to "convince" management/bean counters that the extra cost is worth it to prevent issues down the road, as often these people are driven by short term financial goals rather than the big picture. At least a screw up of this magnitude seems to have driven that point home somewhat. At the end of the day GM is still a company selling a bargain sports car, if they didn't do cost benefit analyses to stay within their budget, we'd quickly have no Corvette at all. Glad to see they have some more "data" to weigh in the future cost benefit analyses.
The way I read it, they initially suspected bad gas due to the spark retard, so then the 101 was added. Once that exonerated that cause, the engineers/techs on site were unable to diagnose the intermittent problem, so as they had no other causes to suggest, MT had nothing else to report.
In those cases people are either seriously injured or killed. No one died in this test. It appears they did successfully rebuild any portion of the car that relate to safety. Not really an apples to apples comparison there.
In those cases people are either seriously injured or killed. No one died in this test. It appears they did successfully rebuild any portion of the car that relate to safety. Not really an apples to apples comparison there.
Last edited by CPhelps; 10-16-2015 at 07:47 AM.
10-16-2015, 07:59 AM
#20
Melting Slicks
Hope there is good weather Monday November 30 at Laguna Seca. Motor Trend has the track rented there that day. Retest of the ZO6 no doubt. We have the El Nino coming. This probably is the test Tadge was alluding to. Who are the very capable competitors?
http://www.mazdaraceway.com/calendar/2015-11
http://www.mazdaraceway.com/calendar/2015-11
Last edited by skank; 10-16-2015 at 08:06 AM.