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[ANSWERED] Why weren't the C7's E85 compatible in order to combat knock and heat?

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[ANSWERED] Why weren't the C7's E85 compatible in order to combat knock and heat?

Old 11-09-2015, 12:24 PM
  #21  
RC000E
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Originally Posted by jvp View Post
Sure, sure. Because the jump from the C5 Z06 to C6 Z06 was a mere 20HP, right? Oh, wait, no, it wasn't. It was 100HP. So moving from 405HP -> 505HP -> ~525HP would have been acceptable to the market?

Keep swinging. You'll eventually get a hit. It's clear you really don't understand what's at play here.
Interestingly though, there is a lot more at play than is generally discussed. One can argue, that the current Corvette Z06 architecture wouldn't be the same, if it wasn't necessary to support the interests of Cadillac/CTS-V. If Corvette didn't have CTS-V to compromise with, what would've the 7th generation Z06 have looked like? I feel pretty sure it wouldn't be the car it is right now.

There is plenty at play...balancing the direction of the American market, vs the European. European would likely prefer a more balanced driver car...say the 525hp, slightly lighter, more track directed machine. A car just as fast, but with an engine designed to propel a Corvette, not a 4200lb sedan. GM certainly can't have the highest hp model in it's company from a Cadillac though...being americans buy cars due to the hp figure on the fender badge anyway...a real shame.

In the end, this is the compromise that must be made for the Corvette to exist, but it also certainly reveals the challenge of trying to compete with a car that isn't compromised in the same manner. Also, with GM directing their efforts at the international market and Porsche specifically, there are going to be an increasing number of buyers who want precision over brute force. When you target Porsche, you bring the GT3/RS mentality into the conversation...that of lighter, more precise...the true driver car. I would LOVE to see Corvette take all it's learned, and begin really sharpening that edge.



By you're example then what's next, 750hp (which we both know isn't happening)? Elimination of the Z06/CTS-V altogether? Z06 should be the driver car...the track machine. In my opinion, this car should've been a ZR1, and the RPO Z06 held at the 505hp level, awaiting a return, when a change in direction takes place. We can't keep going north with hp...something has to give.

Interesting to see what the future holds and what decisions will be made...that's all I know. Designing a sports car for the American mindset/market (hp figures, 1/4 miles, hair in the wind), versus the rest of the world which seems to want a more precision instrument...it's a hell of a tough call and I respect all those in GM who face the jury when they release a new model.
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Old 11-09-2015, 12:53 PM
  #22  
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Originally Posted by jvp
How "in all honesty" do we want to get? Perhaps include why we're (you're)not "behind the curtain" any longer? I bet I know why...

Whoops. I just argued a specific point versus the whole thing. How about I tap out of this and you continue on doing what you're doing.
I'm not behind the curtain at GM because I went from working at a supplier to working at Ford. I'm still very behind the curtain in automotive, just not on Corvette.

Are we going to have a discussion about how Tadge just gave a non-answer or are you going to incite an argument? I'm feeling very insulted by your comments, as they are unwarranted.
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Old 11-09-2015, 12:56 PM
  #23  
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Originally Posted by RC000E
Interestingly though, there is a lot more at play than is generally discussed. One can argue, that the current Corvette Z06 architecture wouldn't be the same, if it wasn't necessary to support the interests of Cadillac/CTS-V. If Corvette didn't have CTS-V to compromise with, what would've the 7th generation Z06 have looked like? I feel pretty sure it wouldn't be the car it is right now.

There is plenty at play...balancing the direction of the American market, vs the European. European would likely prefer a more balanced driver car...say the 525hp, slightly lighter, more track directed machine. A car just as fast, but with an engine designed to propel a Corvette, not a 4200lb sedan. GM certainly can't have the highest hp model in it's company from a Cadillac though...being americans buy cars due to the hp figure on the fender badge anyway...a real shame.

In the end, this is the compromise that must be made for the Corvette to exist, but it also certainly reveals the challenge of trying to compete with a car that isn't compromised in the same manner. Also, with GM directing their efforts at the international market and Porsche specifically, there are going to be an increasing number of buyers who want precision over brute force. When you target Porsche, you bring the GT3/RS mentality into the conversation...that of lighter, more precise...the true driver car. I would LOVE to see Corvette take all it's learned, and begin really sharpening that edge.



By you're example then what's next, 750hp (which we both know isn't happening)? Elimination of the Z06/CTS-V altogether? Z06 should be the driver car...the track machine. In my opinion, this car should've been a ZR1, and the RPO Z06 held at the 505hp level, awaiting a return, when a change in direction takes place. We can't keep going north with hp...something has to give.

Interesting to see what the future holds and what decisions will be made...that's all I know. Designing a sports car for the American mindset/market (hp figures, 1/4 miles, hair in the wind), versus the rest of the world which seems to want a more precision instrument...it's a hell of a tough call and I respect all those in GM who face the jury when they release a new model.
All valid points. I'm unsure of what Tadges response would be for the mid-engined ZR-1 which certainly will make 750 HP.

I feel a lot of stuff on the current model was driven by corporate mandate and not because it was "the best" thing for the program.
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Old 11-09-2015, 01:21 PM
  #24  
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I suppose the best way to describe the Corvette is, "the best potential series of compromises". While ALL auto manufacturers face MANY compromises, when you look at Porsche, Ferrari, Mclaren...these companies have a progressive freedom. With Corvette being high volume, affordable, etc...it does fantastically well given its compromises, but can it ever BE a Porsche, Ferrari or Mclaren? I think it'd take many years and it'd take a healthy GM brand in entirety, to do so. Corvette has the recipe to be a real game changer...it's just not quite there.

Look at the NSX, the FordGT, the Viper, the GTR...and there is one thing in common...they are all built from a blank sheet. The motor isn't shared, no components, etc. In vipers case...it didn't survive and that car, while interesting...was frankly never really even a factor. The NSX has taken YEARS because Honda wanted to be healthy enough to absorb that....same went for the LFA. The LFA was in development for 9 years...Toyota lost money on that car, but that car was a look into what lay ahead and I think history will look back on that car as a beautiful machine. Mclaren is interesting because they are starting from the top and working downard, essentially building a performance brand in reverse of Corvette, working its way toward higher production, more attainable.

You look at Corvette though, this car has expectations on its shoulders...it needs to carry its weight. So, for that reason, it's not on the same playing field. I do think though, that if the base of Corvette...the bread and butter is profitable enough, that a HALO of Corvette could exist and not have such sharing demands placed upon it. It could just simply be a factor in the overall Corvette balance sheet.

If you look at the C7's frame, there is certainly a possibility for modularity there. The front and rear castings are stir welded on, and those members could easily be changed. Not having to do a bunch of interior/seals/etc development certainly could add up to a c7.5 type of era labeled as C8, with a HALO car using the center cell only. Never before has the possibility of a mid engine Corvette ever been so sellable to the bean counters, in my opinion. But 750hp....I disagree...

I believe if that car comes to fruition, it will change direction. It's going to follow the direction that things are going, though I don't think it'll go V6...instead smaller displacement V8 (potentially flat crank), likely forced induction (use the electric supercharger patent they have that drives the compressor with electric motor, boost controlled by programming), with a focus on lighter materials, aerodynamics, etc.

All I know, is I'm hoping that C7 is a transition to something great because C7, while fantastic...feels like a narrow miss...I hate to say it. The more that comes out, the more that the C5Z feels like the best iteration...they went for lightness, precision, stiffness...it was the driver car versus the base. It didn't radically do anything, but driving a base vs a Z06 was like a night and day experience. It was the only time they took the GT3/RS approach. Had they continually developed that, I can't imagine where we'd be. I hope the day comes that Corvette has that true GT3 driver machine...I'd love to see it.

Last edited by RC000E; 11-09-2015 at 01:25 PM.
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Old 11-09-2015, 05:16 PM
  #25  
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The C5Z06 started life as the "Hardtop" which was supposed to be a stripped down driver car. The C6 Z06, ZR1 and the C7 Z06 aren't that as you stated, but I don't think they intended them to be.

There is a flat plane V8 in development, but there also is a twin turbo. GM doesn't know what they want.
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Old 11-10-2015, 04:01 PM
  #26  
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Corvette Racing says bye-bye to E85. They will now run E20 in their racing cars, as will the new Ford GT LeMans car.


Corvette Racing Switching To E20 Fuel For 2016 IMSA Season

Read more: http://gmauthority.com/blog/2015/10/...#ixzz3r7XQfBHQ
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Old 11-11-2015, 01:03 AM
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I am not understanding all his jive here. He makes it sound like running a flex fuel kit wouldn't work on the car. Fasterproms and others have made over 700rwhp on stock fuel system so what gives?
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Old 11-13-2015, 02:17 PM
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Originally Posted by NSC5 View Post
It is always a pleasure to read these detailed explanations of the decision process that led to the current Corvette offerings. A heartfelt thanks to Tadge and JVP for making this happen.

Designing a product that is suitable for and desired by a wide audience that is simultaneously profitable (and meets applicable regulations) is certainly not simple as one finds out once you drill down into the process. Years ago when I was teaching an intro to marketing course I found a simple way of getting this across was asking each student to design their own perfect radio station playlist and most of them were shocked when they found that other students didn't share the same idea of the perfect playlist. No product we own or can buy is absolutely perfect for us as an individual but fortunately a lot of products come very close and I am happy to count the C7 in that group.

Having been involved in manufacturing for 40 years ........ you have stated this very very well
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Old 11-18-2015, 05:53 PM
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This is rapidly becoming my favorite section on the forum. Also, it is doing a tremendous amount to build brand loyalty, for me at least. To be able to ask questions to the senior guy, is unbelievably rare, and simultaneously awesome.
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Old 11-19-2015, 03:20 PM
  #30  
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Originally Posted by descartesfool View Post
Corvette Racing says bye-bye to E85. They will now run E20 in their racing cars, as will the new Ford GT LeMans car.


Corvette Racing Switching To E20 Fuel For 2016 IMSA Season

Read more: http://gmauthority.com/blog/2015/10/...#ixzz3r7XQfBHQ
I think this is significant in some ways.

With the US mandate, it's said that fuel will need to be an approx E27 by 2022. Nascars long time relationship with Growth Energy marked the beginning of their use of ethanol. I'm sure weathertech/IMSA/whoever faced the same situation when it came to their fuel. Ethanol production is higher than ever, but it's still heavily subsidized. I think E85 is likely on a downturn, while these milder blends of E10/15/20+ are the real future.

I was hoping Tadge would hint at a little more with the answer...which was the point of my question really, but....wasn't to be.
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Old 11-19-2015, 06:00 PM
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lol "The production car was designed and built alongside the race car"
except the race car is E85 capable while the production car isn't.
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Old 11-21-2015, 11:49 AM
  #32  
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^ ehhh...a bit trollish there. What fuel a race series uses is political/financial, etc. That really doesn't have anything to do with the street.
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Old 12-31-2017, 12:56 AM
  #33  
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Bumping this to see if we can get an updated response from Tadge.

First, the OP's question was directed to *both* the Z06 and Stingray. Yet Tadge's response as well as all the subsequent discussion has focused on the Z06/LT4.

Within the context of the LT1, we know today that the stock fuel system can easily support E85. Plus the Gen5 V-6 & 5.3L V-8 are flex fuel. Even gmauthority.com still today has a spec sheet for the L86 being flex fuel capable when it was first announced.

So why was the LT1/L86 not made flex fuel capable?
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Old 12-31-2017, 01:31 AM
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seems the disel guys have pumps to support a metric ton of power... they run 15-1 compression and 50psi boost... just saying
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Old 01-01-2018, 12:08 PM
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Now that the ZR-1 is announced to have PORT and direct injection it is obvious that GM has solved the challenge of increasing the volume of fuel to support more horsepower by combining the two. This is what Ford has done across the board with their turbo motors. This should be a much easier way for older cars needing increased fuel volume at pressure to use E-85. Now how to retrofit to the other direct injection motors.
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