New Z06 vs Nismo GTR

[OVERKILL]

Originally Posted By: MalfunctionProne

Originally Posted By: OVERKILL

Originally Posted By: horse123

Originally Posted By: OVERKILL

The 1/4 mile MPH's don't match the HP ratings. The GT-R, heavier, and with 50 less HP, trapped 2Mph higher. So either it is being under-rated by Nissan, that car is a ringer, or the 'vette isn't putting out its rated power.

Hi, do you know the difference between AWD and RWD?

Yes. Have you ever drag raced? Do you understand the correlation between trap speed and HP? If the answer is no to both of those questions then you have no business questioning me on my statement.

+1 and I think it was stupid of him to ask you. AWD likely hooks up better, perhaps better to jump off the line, though RWD turns into an absolute rocket once it hooks up and the power comes on. .. right?

Kind of. Simplified, ET is determined in the first part of the track. How you come off the line, hook-up....etc. This determines how quickly you get down to the other end. ET is massively affected by traction, so an AWD car against a RWD car not on a slick with comparable power output will cut a lower 60ft time and get a better ET. But both cars, assuming they are aerodynamically similar, will cut very similar trap speeds. The reason for this is that trap speed is determined in the latter part of the track. Whether that initial acceleration happens during the first 60ft with a car that hooks solid or after that once a car that has spun gains traction, it happens very quickly. As you go up through the gears, and as your speed increases, the rate of acceleration decreases. This is where how much power a car makes becomes relevant, as in the higher gears, a car with more power will be able to achieve a higher trap speed in that distance. A good example of this would be running a car on slicks vs on a street tire. Feathering the clutch or babying the gas, you'll be able to get a decent ET out of the car on street tires. On a slick, you'll be able to dump the clutch, hook solid, cut a MUCH better 60ft time and get a fantastic ET (for the car). But the MPH between the two runs will be nary identical. This is because what happens in the first little bit of the track has a very significant effect on the time it takes to get to the other end. But the power output of the car didn't change, so once the massive numerical advantage of the gearing used to cover that first bit of track is out of the picture, the rate at which the car accelerates over the remaining distance is the same. So the speed it comes through the traps at the end is very close to the same. Now, you take two Mustangs, one with a 50 shot of nitrous on it and street tires, the other bone stock, but running a drag radial. The Mustang on the tire will come off the line faster than the one with the nitrous, who will have a hard time getting traction. The stock Mustang will 60ft better and may even end up with a better 1/8th mile ET. If the driver in the Nitrous car is really inexperienced and has a hard time with wheelspin, the stock car may even finish the 1/4 mile first. It would have a lower ET. But the car with the Nitrous will trap higher even if it finishes last. The reason is that once it found traction, it was able to accelerate to a higher speed in that distance than the stock car. This is representative of the addition 50HP it received from the Nitrous. Weight is another factor. Two identical cars, but one is 50lbs lighter, that car will be faster. It will have a higher trap speed and a lower ET. So you combine those two things, the additional 50HP and the reduction in weight, and what would the end result be on trap speed? It should be higher (unless it is towing a parachute).

 

[MalfunctionProne]

[quote=OVERKILL][/quote] So while the AWD has a more or less constant velocity of acceleration from a static point, the RWD may in fact have a variance of the same or perhaps greater rate of acceleration from its standstill to the end of the q/mi, where it may reach a higher velocity as a sort of expendature of that pent-up energy generated at the hook-up/etc of the power faster than the AWD at the end, just not perhaps as fast up to about the halfway point? (Read what I said a couple of times, and you will see that while yes I was trying to be wordy... did I at least somewhat accurately describe what you are saying?)

 

[OVERKILL]

No. Re-read what I wrote. The rate of acceleration relevant to trap speed (and a reflection of power being made) happens in the latter part of the run where traction is no longer an issue. The initial "burst" of acceleration that affects ET and 60ft times happens at the beginning of the run and is extremely dependant on traction. AWD cars are much easier to launch than RWD or FWD cars, and will reward you with generally lower and more consistent ET's. But the MPH's they cut at the end of the 1/4 is reflective of the power being put to the ground and subsequently the reason that a car of the same weight with more power will still trap higher, even if the AWD car beats it down the track. Example video:

Mustang runs a [email protected] Subaru runs a [email protected] Subaru wins. Mustang has higher trap speed. You can see that the Subaru comes out of the hole a lot better and puts some good distance between them in the first bit of the track. The rest of the run is the Mustang running it down and it never catches it. Then watch this one. Watch how close they are for the first little bit and then what happens:

 

[02SE]

There are lots of variables. On a prepped drag strip, it's true that a higher horsepower RWD car will still usually be able to hook up fairly early in the run. So it's higher HP will reflect in the trap speed, as compared to a lower HP AWD car that can get out of the hole quicker, and might be able to hold that hole-shot advantage to get to the end of the track quicker, even if it's trap speed is lower. On public roads, or otherwise dirty pavement where so many "Racing Videos" take place, traction is usually at much more of a premium. So conducting short races like a 1/4 mile run on those low-traction surfaces, the high HP RWD car may not get hooked up until well into the run, if at all. In those cases the higher HP RWD car might not show a higher trap speed, because it never could get enough traction to take advantage of it's better power-to-weight ratio.

 

[OVERKILL]

Originally Posted By: 02SE

There are lots of variables. On a prepped drag strip, it's true that a higher horsepower RWD car will still usually be able to hook up fairly early in the run. So it's higher HP will reflect in the trap speed, as compared to a lower HP AWD car that can get out of the hole quicker, and might be able to hold that hole-shot advantage to get to the end of the track quicker, even if it's trap speed is lower. On public roads, or otherwise dirty pavement where so many "Racing Videos" take place, traction is usually at much more of a premium. So conducting short races like a 1/4 mile run on those low-traction surfaces, the high HP RWD car may not get hooked up until well into the run, if at all. In those cases the higher HP RWD car might not show a higher trap speed, because it never could get enough traction to take advantage of it's better power-to-weight ratio.

This is true. My references are all in regards to a race occurring at a track where the distance of the run is going to be accurate, the surface is going to be properly prep'd and trap/ET would be verified by proper equipment and the run started with a tree rather than a kid waving a scarf The video at the beginning of this thread was performed on a proper track and the closeness in ET (11.0 vs 11.4) indicates that they didn't have much of a problem hooking the 'vette up (and the tires were very nice too, as I'm sure you noticed). In fact, they were closer on that than I expected. My issue was with the trap speed difference given the closeness in ET. Unless the 'vette was pulling a parachute, it has a 50HP advantage and less weight. It should have trapped higher. It does have quite the wing on it, but then so does the GT-R. Maybe not as severe though, given the difference in the lips between the two. If the aero package on the 'vette is negating the weight and power advantage to the point that it traps lower, I would be very surprised. But that's what Steve seems to think is happening here I'd think that the GT-R perhaps is simply making more than what it is said to be making (kind of like the '03/'04 Cobra Mustang). Which then causes the whole works to make sense.

 

[LFN]

More bad news about the C7 Z06 in the Motor Trend mag currently out that delves deeper into this shootout. -After one lap the computer was cutting HP on the Vetter due to overheating issues. One. Lap. This is supposed to be a track capable car right? -Engine heat in traffic cook's the drivers feet & heats up the cabin considerably. None of this was happening with the Z51 package Vette. What a disaster this car is imho.

 

[mjoekingz28]

Didnt they do away with oil coolers on Vettes?

 

[Mykl]

I love the Z06, but my money would probably go towards the GT-R. I have enough track experience to know that I might be a little timid about keeping a 650 hp RWD car on the track with the ends pointed in the right direction. Obviously the GT-R is a monster in its own right, but the AWD increases the range of throttle you can use to keep the rear pinned.

 

[MetalSlug]

Im chevy fan, but I gotta give to GT-R , I seen them doing incredible thing on the street of texas.

 

[zuluplus30]

Originally Posted By: mjoekingz28

Didnt they do away with oil coolers on Vettes?

No.

 

[zuluplus30]

The GT-R is a boss. I really like the Vette for what it is, but the GT-R is and always has been batting way out of it's league. It allows the average driver to extort 100% of it's ability. Easy. Stupid fast. Repeat.

 

[Mykl]

Originally Posted By: zuluplus30

The GT-R is a boss. I really like the Vette for what it is, but the GT-R is and always has been batting way out of it's league. It allows the average driver to extort 100% of it's ability. Easy. Stupid fast. Repeat.

Yeah, I think the difference comes down to two different types of performance enthusiasts. The ones who prefer to focus on mastering a machine, and those who prefer to focus on mastering the road. I wouldn't exactly classify the GT-R as "easy", but I suppose relative to some of its competitors it is on the user-friendly side of things. Of course, this is all from what I gather through reading, I've never driven one.

 

[LFN]

2015 Chevrolet Corvette C7 Z06 escalates overheating problems already present in Corvette C7 Stingray Randy Pobs't Road Atlanta run continues to make waves in the automotive world but certainly not in the way +Tadge Juechter has envisioned. If the Nurburgring embarrassment was already not bad enough for the 2015 Z06, things got considerably worse after Randy Pobst managed measly four laps at Road Atlanta before the newest Z06 did the trademark C7 move: lit up the diagnostics screen like a Christmas tree and assumed the ever popular limp mode due to engine and transmission severe overheating conditions. The problem with overheating is not particularly new to Corvette, the last generation of ZR1 was notorious for overheating engine and transmission, proudly attesting to the unfortunate fact that supercharging and track duties rarely get along without negative effects, mainly heat soak. However, there is a slight difference here: at least according to +Tadge Juechter , the presence of heat extractor in the hood was a measure taken to specifically address the overheating and heat soak issues. Two possibilities here: either the heat extractor system is insufficient (assuming it works at all) OR the drivetrain suffers from considerably more heat related problems then originally anticipated. There is no doubt that Juechter and his +General Motors engineering team already miscalculated automatic transmission heat build up, hence there is that second extra stupid and inefficient cooler but... what about the rest of the drivetrain? Apparently while juggling the fuel economy and emissions aspects, things might have leaned out too much? Direct injection tends to keep engines on lean side already but how about Juechter not getting the tuning software correctly? The heat soak is already present on Z06, the fact that Pobst's car was pulling timing and throwing error codes is a very condemning evidence. Furthermore, Pobst managed to get worse lap time with each next lap, until the car refused to run altogether. Overheated engine, overheated supercharger, overheated transmission, overheated E differential. Where is this going to stop? What is this car exactly good for? So far, the new Z06 is good for Cars and Coffee, 4th of July parade, single dragstrip run and occasional AARP trip. Not much of an actual high performance or even less so track car... LOL Posted 4th December 2014 by Peter MJ 0 Add a comment PeterMJ's Corvette C7 Stingray and Z06 Exposed How General Motors failed to create a better Corvette Classic Home Corvette C7 Stingray Active Fuel Management Problems MAR 4 General Motors continues to deliver 2015 Corvettes C7 Z06 with cracked tires, buyers facing lengthy replacement times due to tire shortages Hard to tell who is dumber, +Tadge Juechter claiming credit for creating a super turd equipped with summer only tires prone to cracking during winter months or +General Motors producing these cars in Bowling Green, KY during sub zero winter temperatures, rolling them out in the freezing weather and then passing them on to the dealers who in turn pass them on the buyers... Hmmm... sounds like a big cluster [censored]... This blog already pointed out the hypocrisy of GM warning the dealers about Michelin Cup 2 tires and about not moving the cars in low temperatures while doing the exact thing itself... But... the cracking tires are not limited to the Z07 equipped with Cup 2 tires, the base Z06 Michelin Pilot Super Sports crack just as easily which makes the current cluster [censored] growing to nth power. Great job Juechter and GM.

 

[Mykl]

^ how do they not know that these things would happen prior to releasing the car? With a Z06 I'd have expected test drivers to be wailing on the thing on a track for hours on end, testing and gathering data for the engineers to look at.

 

[LFN]

They had to know, I agree. They must be counting on Corvette loyalists to buy the car regardless..hope this car bombs, because it truly deserves to. Then again GM knows most owners are 50 something guys who use them as boulevard cruisers. Real drivers should get a GTR or 911, or GM's track car that actually works, the Z28.

 

[MarkM66]

So the supercharger just creates to much heat. I'm sure the older LS7 Z06 is fast enough for 99.9% of "drivers."

 

[d00df00d]

A C7 Z06 with an LS7 might just be a better car, honestly. Less power = slower in a straight line, but who cares at this point? Lighter engine = better around a corner, better on the brakes Less heat = better tolerance of track use Wish Chevy had gone the same route as Ford supposedly did with the new GT350: make it good for actual track use, not bench races.

 

[dailydriver]

Originally Posted By: d00df00d

A C7 Z06 with an LS7 might just be a better car, honestly. Less power = slower in a straight line, but who cares at this point? Lighter engine = better around a corner, better on the brakes Less heat = better tolerance of track use Wish Chevy had gone the same route as Ford supposedly did with the new GT350: make it good for actual track use, not bench races.

Although I disagree with all of the 'Godzilla' worshippers on here, I could NOT agree more with the above. The Z06 should be 7 liter, NA ONLY, with a REAL, external, multi-stage oil pump system, and NO DOD/AFM AT ALL!! If they have a burning desire to make a boosted version, that should be the ZR1. Sadly, (probably due to CAFE/EPA [censored]) they could not just put a higher tune/bigger cam, more open heads/more open exhaust LS7 in it, or even a non-AFM/DOD, hotted-up, NA, LTI in it. I would just buy a base C7, and turn it into a track car on my own with help from a builder/tuner and a well built Mast crate (or Katech full race, ITB, C5/6R if one wants to get REAL crazy!) engine, custom valved Penske reservoir coilovers, and maybe one of the less(er) costly sequential gearboxes.

 

[mjoekingz28]

Originally Posted By: MarkM66

So the supercharger just creates to much heat. I'm sure the older LS7 Z06 is fast enough for 99.9% of "drivers."

I pretty much agree. Instead of adding weight, subtract it. A five speed works fine, the T56 is plenty good, like a five with a tall OD. But seven? Maybe they are just being innovative and trying new stuff. Personally, I really like the C5 ZO6 and believe it to be a great strip, street and circuit car as well as a showcar and collector. I think they could make a lighter version for racing, but i dont see how you could improve on it. Lol, like Halo c.e. was it, I knew before it came out that Halo 2 wasnt going to be any good. You just cant improve on something already great. I wouldnt mind a 350-450, hmm 405hp, lol in a 3000lb car with manual steering. Put the fun and involvement back into sportscars.

 

[hattaresguy]

From what I have seen at Limerock GTR's are animals, it takes a heck of a driver in a heck of a car to give a so so driver in a GTR a run for his money. The AWD 911 is another animal. High HP RWD cars are always a bit slower unless one heck of a driver is inside, they just can't hook up as well coming out of the corners. On the straights they do fine, braking they do fine, but coming out of the corner is where the Ninja magic of the GTR shines, all that power goes down and the computers make it happen.