Actual RWHP for new Z/28?

[Sven59]

Originally Posted by 360ss

My wife owns a 2011 cts , luxury horsepower just doesn't sctatch my itch!! Be more specific As far as what track capabilities ? I was only addressing to ur message you posted.

What I meant is they designed the rearend of the Z/28 for track use. If you change that to be beefier for the strip it might effect its performance on the track. I am not an expert, but I would think if the engineers could have made it for both wouldn't they or does it come down to the COPO is for the strip, the Z/28 is for the track and the ZL1 does everything.

[Zfatuated]

Originally Posted by Sven59

What I meant is they designed the rearend of the Z/28 for track use. If you change that to be beefier for the strip it might effect its performance on the track. I am not an expert, but I would think if the engineers could have made it for both wouldn't they or does it come down to the COPO is for the strip, the Z/28 is for the track and the ZL1 does everything.

Your homework is to learn and report back on different types of differentials and how, exactly, each is better or worse for a given application. It's not a hard assignment, in fact, if you put forth even a modicum of effort, you can earn the adulation and respect of your peers.

Bonus points for discussing the effect of weight (reduction) as it pertains to road course cars, drag race cars and street cars.

[Sven59]

Originally Posted by Zfatuated

Your homework is to learn and report back on different types of differentials and how, exactly, each is better or worse for a given application. It's not a hard assignment, in fact, if you put forth even a modicum of effort, you can earn the adulation and respect of your peers.

Bonus points for discussing the effect of weight (reduction) as it pertains to road course cars, drag race cars and street cars.

The dog ate it!

[DGthe3]

Originally Posted by SSpade22

I’ve seen in magazines the HP that the new Z28 will put down at the fly, but I haven’t seen any actual RWHP numbers. Does anyone know where it will be in that aspect, and how much lighter is the Z28 vs. the 2010 SS.

Its very difficult to get RWHP for a car that has never seen a dyno outside of a GM R&D centre. It gets even more difficult to guess when we don't know what the final flywheel power is going to be. All that is official is that the LS7 will provide at least 500 hp.

But personally, I wouldn't be too worried about what a stock Z/28 makes at the wheel. Namely because its just a number that depends on a whole host of factors beyond the car itself. What type of dyno is it, what are the conditions its being run in, when was the dyno last calibrated, is the operator conservative or generous, and so on. So it is entirely possible that one Z/28 could do a few pulls on a dyno and get a reading of 410 rwhp and the owner would think they've got a slug for a car. But if they went down the street to a different shop the same car could hit 450 rwhp & sunofabitch ... their car is under-rated!



As for weight, the target was 100 lbs less than the SS and from what I recall, they have surpassed that goal without too much trouble. So it will probably end up right around 3700 lbs when its done.

[2cnd chance]

Originally Posted by DGthe3

As for weight, the target was 100 lbs less than the SS and from what I recall, they have surpassed that goal without too much trouble. So it will probably end up right around 3700 lbs when its done.

That's my guess as well, right around 3,700.

[Number 3]

A lot depends on if the LS7s are already made. Are they building fresh brand new engines in BG or are they using up units already made at Wixom? If new then there may be room for tweaks. If pre built then you are counting on intake and exhaust for better breathing. I think 520 will be tops. So rear wheel not much more than the good ol Z06

[2cnd chance]

Originally Posted by Number 3

A lot depends on if the LS7s are already made. Are they building fresh brand new engines in BG or are they using up units already made at Wixom? If new then there may be room for tweaks. If pre built then you are counting on intake and exhaust for better breathing. I think 520 will be tops. So rear wheel not much more than the good ol Z06

Do you know what the Z06 had for RWHP? Thanks.

[LOWDOWN]

Mass, and unsprung weight, reductions were paramount, without breaking the Bank. 1LE rear axle assembly (minus brakes etc.) is about 40# less than ZL1...which is about 20# less than the CTS-V.

Typical untouched C6 Z06s range from about 420 to 440 rwhp (different dynos on different days). The "targeted 450" is assuming a good "tune" from the fine folks @ GM...

[2cnd chance]

Thanks!

[The DeLoach 27]

Originally Posted by SUKXOST

yeah 18% DT loss seems high. Mine was less than 12% loss. 426hp and my baseline was 378WHP.

I'm betting 445+WHP

Typically it is only a 12-15%, gross h.p. vs. RWHP.

[Cody6.2]

Originally Posted by The DeLoach 27

Typically it is only a 12-15%, gross h.p. vs. RWHP.

There is no real percentage of drivetrain loss as it's a static figure from stock to whatever horsepower.

[DGthe3]

Originally Posted by Cody6.2

There is no real percentage of drivetrain loss as it's a static figure from stock to whatever horsepower.

Its not a simple percentage, but that is a much more accurate rule of thumb than a static figure is.

You are probably thinking of the power that it takes to accelerate a wheel or drive shaft, and its true that these things take only a fixed amount of power to be accelerated (until you swap them out for something different of course). But the instant that they are up to speed, they no longer rob anything of any power (and they also 'release' power as you try and decelerate). This does not hold true for the gears in the transmission & differential, or the half-shafts going out to the wheels, or the bearings or tire flex any of the other sources of friction. Those losses can be approximated as a percentage of input power, though in reality its a somewhat complex curve that depends on a number of factors. Point being, if you run your car stock on a chassis dyno and calculate that it lost 55 hp ... don't assume that after you've supercharged it its still only losing 55 hp.

[LeanPocket]

this will be a 11 second car with the right driver, 11 consistent with a auto swap.

[Norm Peterson]

With an auto swap you might just as well peel the Z/28 badges off while you're at it.


Norm