Actual RWHP for new Z/28?

[LOWDOWN]

Originally Posted by Norm Peterson

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


Norm

If a strip teaser is what you seek, start with an SS, and if an automatic is your pleasure, start with an SS. A crate LS7, or a fortified LS3/L99 (de-AFM'd), combined with a ZL1 carrier and axles or a 9" swap, will have you buck$ in-pocket and probably a happier camper...

[DrkPhx]

It has a CAI and Tri-Y headers with high flow cats and better exhaust so I think it will make an easy 450 rwhp.

[Doc]

Originally Posted by Cody6.2

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

It isn't a static figure; it's a composite percentage that's the result of the various resistances that are in between the engine and the wheels. The factors are: flywheel (design and weight), clutch (design, style and weight), transmission (design and efficiency), driveshaft (style, weight, efficiency), differential (design, style, efficiency), wheels (weight). And in all those closed assemblies there's the efficiency of the oil inside and how well it reduces friction and deals with heat. The inefficiencies themselves aren't even static; they change (usually getting worse) as speed, torque and heat increase.

There's also the quality of the various parts and components as to how well they're made, how true to spec, and how well-balanced they are. A part that works fine at 4000 rpm may not work as well at 7000 rpm; it may start to distort and lose efficiency thereby increasing power loss.

All these factors add up to a composite loss of power expressed as a percentage. The initial percentage is not static either. It's based on the stock configuration of the vehicle. Start changing things and it can go up or down. Start adding power without changing anything else, and the loss percentage is likely to increase due to everything being pushed above its designed operating level.

If you leave the engine alone but start improving the efficiency of the drivetrain by reducing rotating weight, reducing friction with upgraded oils, upgrading components to higher spec, etc. you will see an increase in rwhp without adding 1 hp to the engine. In reality you haven't gained hp, you've gained efficiency which is allowing more hp to get through to the wheels. You have reduced drivetrain loss.

12-15% loss is a rough average based on the stock configuration but it gives you a starting point as to what to use to calculate performance efficiency.

[Number 3]

Originally Posted by LeanPocket

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

What RWHP are you basing that on?

A Stock Z06 with 335 rear tires and 450 to 500 pounds less mass to launch is a high 11 second car.

I don't think a ZL1 with an automatic even comes close to being an 11 second car and the Z/28 will only be 300 pounds lighter than that car. Isn't a Stock ZL1 running about 12?

You must be hoping for some big HP improvements in the LS7. The very slight mass reduction sure isn't going to shave a second off.

[LOWDOWN]

Part of the confusion comes from the erroneous interpretation of the word "track". Some use the word to indicate "strip", and others use it to indicate "road course". GM's use, in this particular case, is solely to mean "road course".

Adding DRs and implementing redline launches with the 1LE carrier/axles, with almost 500 lb-ft in OE tune, will mean non-warrantable harm...

[mkorgan]

Originally Posted by Number 3

What RWHP are you basing that on?

A Stock Z06 with 335 rear tires and 450 to 500 pounds less mass to launch is a high 11 second car.

I don't think a ZL1 with an automatic even comes close to being an 11 second car and the Z/28 will only be 300 pounds lighter than that car. Isn't a Stock ZL1 running about 12?

You must be hoping for some big HP improvements in the LS7. The very slight mass reduction sure isn't going to shave a second off.

My stock ZL1 (Rotofab CIA) has a best 11.84 1/4 time.

[Awill]

very interesting

[Number 3]

Originally Posted by mkorgan

My stock ZL1 (Rotofab CIA) has a best 11.84 1/4 time.

A pretty solid performance and probably driver aided from practice and experience. Just not sure how a Z/28 beats you and your car by another .8 seconds with 300 pounds being the only advantage.

If you want a drag car that is what the COPO was built for. The Z/28 was built for the less straight track.

[LeanPocket]

Originally Posted by Number 3

What RWHP are you basing that on?

A Stock Z06 with 335 rear tires and 450 to 500 pounds less mass to launch is a high 11 second car.

I don't think a ZL1 with an automatic even comes close to being an 11 second car and the Z/28 will only be 300 pounds lighter than that car. Isn't a Stock ZL1 running about 12?

You must be hoping for some big HP improvements in the LS7. The very slight mass reduction sure isn't going to shave a second off.

the record for a stock z06 with stock tires is a 10.9x
http://forums.corvetteforum.com/c6-z...fast-list.html with mid to low 11's being the norm where i live with the drivers i know personally.

a high 11 is very realistic for the z28 at 505 fwhp with the driver mod. Then again, I'm from texas, with good DA's. If you're granny shifting, ofcourse it'll be a twelve second car.. or even a 13.

I ran 11.6x in my old ls1 at 470'ish rwhp through an auto peddling the 2-3 shift. Car weighed 3550-3650 with me in it.

zl1's are capable of 11's
https://docs.google.com/spreadsheet/...1E2SVdWd3lkOUE

[LeanPocket]

Originally Posted by Norm Peterson

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


Norm

nothing wrong with a autoswap to run decent times at a drag strip.

Its been done to zr1's and z06's with fantastic results, and there will be the few that will do it.

Drop in a built RPM 4l80 with a custom stall and run 11's all day.

Too each their own i suppose.

[Number 3]

Originally Posted by LeanPocket

the record for a stock z06 with stock tires is a 10.9x
http://forums.corvetteforum.com/c6-z...fast-list.html with mid to low 11's being the norm where i live with the drivers i know personally.

a high 11 is very realistic for the z28 at 505 fwhp with the driver mod. Then again, I'm from texas, with good DA's. If you're granny shifting, ofcourse it'll be a twelve second car.. or even a 13.

I ran 11.6x in my old ls1 at 470'ish rwhp through an auto peddling the 2-3 shift. Car weighed 3550-3650 with me in it.

zl1's are capable of 11's
https://docs.google.com/spreadsheet/...1E2SVdWd3lkOUE

I was just quoting magazine numbers. But running 11s. Is way different than 11 flat which caused my comment.

By the way are the Z06s bone stock running mid 11s?

[LeanPocket]

Originally Posted by Number 3

I was just quoting magazine numbers. But running 11s. Is way different than 11 flat which caused my comment.

By the way are the Z06s bone stock running mid 11s?

i meant 11.xx second in general, not 11 flat.

I know three people locally that run 11's in stock z06's. Not consistent, but PB's were in the 11's.

[SSpade22]

Originally Posted by Norm Peterson

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

My SS is an auto (built 4L80e); I don’t know why everyone is always talking down about autos at the strip. My times are always consistent (6.60 in the 1/8th on 20in wheels with a 1.50 60ft time) while my manual buddies are all over the place.

I would be willing to bet that GM makes an automatic version of the Z/28 just like they did the SS, and I doubt anyone will be taking the badges off it

[2cnd chance]

Originally Posted by SSpade22

My SS is an auto (built 4L80e); I don’t know why everyone is always talking down about autos at the strip. My times are always consistent (6.60 in the 1/8th on 20in wheels with a 1.50 60ft time) while my manual buddies are all over the place.

I would be willing to bet that GM makes an automatic version of the Z/28 just like they did the SS, and I doubt anyone will be taking the badges off it

His comment has nothing to do with automatics good or bad at the drags.

The Z/28 is going to be a raw drivers car...as it was from the start. It was born with only a manual and this new Z/28 is already said to be manual only. Most anyone buying a new Z/28 is looking for a track ready car. Yes some will 1/4 mile it, but that is not its purpose.