Shno's House of Z

[Mr. Wyndham]

Originally Posted by Bhobbs

I have a hard time believing Ford could make 526 but GM can't.

Generally, I agree...but might we have found the point where DOHV, smaller-displacement offers an advantage?

Don't forget...the hp of Ford's engine is most generated by very high engine speeds. It's lower on torque than even the 'old' LS7 was...

The most challenging portion of the emissions tests to beat is cold startup and idle. It also sounds like powertrain engineering wanted to meet internal standards for cost and durability. So maybe they *could* get the power and emissions...but not the others, too?

[2cnd chance]

Isn't there a cam and heads kit for the LT1 from GM? You'd think they could of used it and adjusted the timing to solve any emissions issue.

[Mr. Wyndham]

Originally Posted by 2cnd chance

Isn't there a cam and heads kit for the LT1 from GM? You'd think they could of used it and adjusted the timing to solve any emissions issue.

Is it CARB-legal?

[Bhobbs]

Originally Posted by Mr. Wyndham

Is it CARB-legal?

I doubt it is. GM would have to certify it and I guess that's an expensive process.

Originally Posted by Mr. Wyndham

Generally, I agree...but might we have found the point where DOHV, smaller-displacement offers an advantage?

Don't forget...the hp of Ford's engine is most generated by very high engine speeds. It's lower on torque than even the 'old' LS7 was...

The most challenging portion of the emissions tests to beat is cold startup and idle. It also sounds like powertrain engineering wanted to meet internal standards for cost and durability. So maybe they *could* get the power and emissions...but not the others, too?

Could be an advantage of the TiVCT.
If they built a 6.2 l LT6, would the cold start and idle emissions be drastically different than the LT1?

I thought I read they wanted to keep AFM and the lifters were an issue at the lift and rpm they needed. I"ll try to find that article again.

[2cnd chance]

Originally Posted by Mr. Wyndham

Is it CARB-legal?

Originally Posted by Bhobbs

I doubt it is. GM would have to certify it and I guess that's an expensive process.



Could be an advantage of the TiVCT.
If they built a 6.2 l LT6, would the cold start and idle emissions be drastically different than the LT1?

I thought I read they wanted to keep AFM and the lifters were an issue at the lift and rpm they needed. I"ll try to find that article again.

I'm not sure.
I think more than cost and such the concern is being too close to the Z06 track times.

[DGthe3]

Originally Posted by Mr. Wyndham

Don't forget...the hp of Ford's engine is most generated by very high engine speeds. It's lower on torque than even the 'old' LS7 was...

It barely makes more torque than the plain old LS3

The most challenging portion of the emissions tests to beat is cold startup and idle. It also sounds like powertrain engineering wanted to meet internal standards for cost and durability. So maybe they *could* get the power and emissions...but not the others, too?

Thats my thinking on why GM didn't do an LT7. They might have been able to hit their power requirements, but it would fail emissions. Adding technology could get it to hit both targets, but then cost goes up and reliability goes down.


As for what their goals actually were? We'll probably never know. But my hunch is that performance wise, they were looking to match or beat the ZR1. Not necessarily in outright power, but 0-60, 1/4 mile, and around a road course? Absolutely. Unfortunately, in a car that would weigh about 3400 lbs that would take at least 600 hp. Cost, well it makes sense that they'd want it to be less than the ~17k or so that the LS7 does. Emissions need to be met, there isn't much of a choice on that one but if fuel economy is lumped in with that, they'd have a lot more flexibility.

Durability is another one that is a mystery. In theory, they'd need to make it just as tough as any of their other engines -perhaps even moreso since they know that they'll be abused. But the cold hard facts are that since it would be a low volume, high performance engine they could allow 10x the 'normal' failure rate and it would still be only a couple more engines per year that they'd have to replace under warranty -even fewer if they denied coverage due to modifications or 'abuse'.

[Mr. Wyndham]

Originally Posted by DGthe3

Durability is another one that is a mystery. In theory, they'd need to make it just as tough as any of their other engines -perhaps even moreso since they know that they'll be abused. But the cold hard facts are that since it would be a low volume, high performance engine they could allow 10x the 'normal' failure rate and it would still be only a couple more engines per year that they'd have to replace under warranty -even fewer if they denied coverage due to modifications or 'abuse'.

annnddd....durability has another face within GM's test labs.

For example, they test a suspension to 300,000 miles, and then warrant it for 100,000. I can only imagine what sort of tests they'd subject a powertrain to.

[Bhobbs]

Originally Posted by 2cnd chance

I'm not sure.
I think more than cost and such the concern is being too close to the Z06 track times.

It would be interesting to see someone take a GSZ07, bump it to 500+ and lap it against a Z06.

[2cnd chance]

Originally Posted by Bhobbs

It would be interesting to see someone take a GSZ07, bump it to 500+ and lap it against a Z06.

Yep.

[Number 3]

Originally Posted by Mr. Wyndham

annnddd....durability has another face within GM's test labs.

For example, they test a suspension to 300,000 miles, and then warrant it for 100,000. I can only imagine what sort of tests they'd subject a powertrain to.

It just seems like 300,000 miles, but it is generally just the high 90 %ile user. That's why when you look at something as simple as door slam test cycles it seems crazy. No one would ever do it that often..............if you think of the average owner. But the 99 %ile owner does some pretty extreme stuff.

[Number 3]

Ok, here is my new concern.

GM is spending a LOT of time and money making verrrrry special Camaros and Corvettes.

Within just a few weeks we get a 1LE and a GS. Likely in New York we will get something else on top of that, predicting ZL1. And then a Z/28 somewhere down this path of awesome cars.

So how about a lowly little hot hatch or Sedan even? Not just that Ford has the Focus in multiple performance oriented variants, but whether it's Buick or Chevy, GM needs a car with the 2.0T, great brakes and handling.

Now GM did this once and got burned. We had BOTH an Cobalt SS and an HHR SS. Both sold like crap and were cancelled. So maybe GM has decided this isn't worth the effort.

But the upcoming new Verano sure doesn't look like there is any performance there and as sweet as the new Cascada looks, it does 0 - 60 in like 9 seconds. Talk about slow in todays market.

So until the mid engine Corvette or Zora, I think we've seen everything in the Corvette arsenal. Unless that mythical NA LTx comes along. Fingers still crossed.

And the only question we have left is does the ZL1 outfitted with the CTS-V hardware squeeze out the Z/28? I still think that even without a NA engine (fingers are still crossed) there is room for a ZL1 with the LT4 and a lightweighted version with CC brakes to be a track focused variant. But without that LTx, the place for that car seems tougher to carve out.

And you are all wondering how much skill it takes to type with your fingers crossed aren't you.

[Mr. Wyndham]

Originally Posted by Number 3

It just seems like 300,000 miles, but it is generally just the high 90 %ile user. That's why when you look at something as simple as door slam test cycles it seems crazy. No one would ever do it that often..............if you think of the average owner. But the 99 %ile owner does some pretty extreme stuff.

Very interesting, indeed!

Originally Posted by Number 3

Ok, here is my new concern.

GM is spending a LOT of time and money making verrrrry special Camaros and Corvettes.

Within just a few weeks we get a 1LE and a GS. Likely in New York we will get something else on top of that, predicting ZL1. And then a Z/28 somewhere down this path of awesome cars.

So how about a lowly little hot hatch or Sedan even? Not just that Ford has the Focus in multiple performance oriented variants, but whether it's Buick or Chevy, GM needs a car with the 2.0T, great brakes and handling.

Now GM did this once and got burned. We had BOTH an Cobalt SS and an HHR SS. Both sold like crap and were cancelled. So maybe GM has decided this isn't worth the effort.

But the upcoming new Verano sure doesn't look like there is any performance there and as sweet as the new Cascada looks, it does 0 - 60 in like 9 seconds. Talk about slow in todays market.

I was talking about this to my friend "The Blur"...and it would seem that, for example, even though the Sonic RS isn't actually faster than the Fiesta ST (it handles better, but doesn't at all accelerate comparably)...it sells better. Well, actually, the whole car line sells better.

I can imagine the investment in the turbo version of the Cobalt SS, including Brembo brakes, etc...and then as fast and awesome as it was...it didn't sell very well. But how much of that flop was the interior and the reputation of the Cobalt? They did replace it, after all, with a Cruze.

I've been dying to see a Cruze SS...they could market the same way they marketed the Z06..."developed with input from the race car"

Originally Posted by Number 3

And the only question we have left is does the ZL1 outfitted with the CTS-V hardware squeeze out the Z/28? I still think that even without a NA engine (fingers are still crossed) there is room for a ZL1 with the LT4 and a lightweighted version with CC brakes to be a track focused variant. But without that LTx, the place for that car seems tougher to carve out.

And you are all wondering how much skill it takes to type with your fingers crossed aren't you.

I wonder how they'll go about it. We already have a 1LE...which means the "Z-suspension" approach has already been used on Camaro...no Z/28 that way...

It's likely we'll get the "everything thrown at it" approach with the ZL1...

Which just leaves the "stripped-down" race car approach like last generation. But there doesn't appear to be an "appropriate" engine like there was in 2014. So will they strip down the 1LE.....or will they strip down a ZL1?

[90503]

Morph that Cruze into a 2-door "Nova".....Nova SS, Nova Hatchback, Nova Wagon, Nova "Nomad"....

If no street legal unique Z/28 engine is available, build the Z/28s similar to the COPOs...
Crate motors, bare bones, track only, not for street use, etc....

[2cnd chance]

50th Anniversary. There's no way Chevy is going to miss a 50th Z/28, not a chance. That would be a HUGE blunder. I think we're going to see a new direction in engines...DOHC TT and I think we'll see it in the Z/28. A High revving smaller displacement V8 TT.

The small performance car is/has been fading in my opinion. Many of those guys have turned to the new crop of Muscle Cars, Camaro, Challenger, Mustang, etc. Ford can get away with it as they have a history in their Ralley cars.