Houston - 10-11-2004

[sameerrao]

Originally Posted by everso Originally Posted by sameerrao My S4 is pretty fuel efficient on the highway for a heavy piggie: - 75 mph on cruise control - 26 mpg+ depending on traffic - 90 mph on cruise - 21.9 mpg - 120 mph (definitely not on cruise) - 15 mpg (approximate) i get on average, between 30 and 35mpg on the freeway! between 80 and 90mph. but on the downside...in the city, i get about 16mpg have you EVER seen a mileage chart that says 16/33mpg? LOL. ridiculous!

That's stunning fuel economy for such a fast pace. In the city I also get anywhere between 15 - 19 mpg - if it is a complete stop-go situation it drops to 12/13 mpg - fucking Testarossa numbers

That's just because my car weights about 300 lb more than yours - I carry the equivalent of a "Bubba" around all the time

[RC45]

Originally Posted by sameerrao I think the 4 mpg must be because he was in the hard acceleration mode - i mean the Vette must be in third/fourth gear.

Yes - that is 70% throttle... in 4th going for 5th.

Sustained 10% throttle at 70mph sees25mpg institaneous consumptio and about 20mpg average for the entire trip - stop/idle/go.

But anytime you are 60%+ throttle the V8 shows it's true colours - and crusing at 120+ is a sustained 8mpg with instantaneous 4mpg as shown..

Slip that puppy into 6th gear at 80mph and you get 28mpg.. .

But who wants to cruise in 6th at 1200rpm when you could be in 5th at 3500 - or better yeat 4th at 6000

[sameerrao]

Originally Posted by RC45 But who wants to cruise in 6th at 1200rpm when you could be in 5th at 3500 - or better yeat 4th at 6000

Man that's serious lengthening of the top two gears - my car drops about 800- 1100 rpms or so from 4th to 5th to 6th.

Yours falls off a cliff. 6000-3500-1200. Do you get any worthwhile acceleration in 6th at all... seems like a useless gear to me

[BADMIHAI]

Do you get any worthwhile acceleration in 6th at all... seems like a useless gear to me

Of course he does. 100-160 mph in 2 s. and 160-242 mph in 3 s. And all at 28 mpg. because A. It's a Corvette and B. It's in 6th gear. Of course, only rocketed off from a plane.

On the other hand you are one brave driver. Sustaining 110 mph is almost begging to get caught.

[mindgam3]

i think 6th in the corvette is an overdrive gear is it not RC?

[sameerrao]

Originally Posted by mindgam3 i think 6th in the corvette is an overdrive gear is it not RC?

Yes ... If I recall it reaches it top speed in 5th not 6th... it was something to boost fuel mileage along with the 1st to fourth shift under part throttle.

[nthfinity]

magazine data shows this, or something similar for the Z
6th gear accelleration from 50-70mph 11.1 seconds
for the C6
6th gear accelleration is 9.6 seconds

if my memory serves accurately... im also thinking that that is actually for 5th gear rather then 6th, since the ratio was changed in the C6

[RC45]

Yes - 6th is a double over-drive. This gear combined with the skip-shift as sameer points out are what qualifies the Vette to by-pass Gas Guzzler Tax and still collect $200...

[sameerrao]

Is it possible to substitute 6th gear with a more direct gear with higher gearing ... do you know if anyone has done it ... Would be interested to see the top speed then

[RC45]

Originally Posted by sameerrao Is it possible to substitute 6th gear with a more direct gear with higher gearing ... do you know if anyone has done it ... Would be interested to see the top speed then

There was a gent from the Chicago area that used to post on the Z06 forums - he had a custom ratio'ed transmission in his 900hp+ Viper that he was building specifically for top end and 1/4, 1/2 and 1 mile runs.

I have always thought that after a $30,000 engine swap a $10,000 custom ration transmission would be the perfect mod.

With a taller rear end, and closer raitos like the Macca F1 even a 750hp Vette would surely be able to run to 250mph+ (considering the LPE 427TT already runs to 220ish.

[mindgam3]

Originally Posted by RC45 Originally Posted by sameerrao Is it possible to substitute 6th gear with a more direct gear with higher gearing ... do you know if anyone has done it ... Would be interested to see the top speed then There was a gent from the Chicago area that used to post on the Z06 forums - he had a custom ratio'ed transmission in his 900hp+ Viper that he was building specifically for top end and 1/4, 1/2 and 1 mile runs. I have always thought that after a $30,000 engine swap a $10,000 custom ration transmission would be the perfect mod. With a taller rear end, and closer raitos like the Macca F1 even a 750hp Vette would surely be able to run to 250mph+ (considering the LPE 427TT already runs to 220ish.

it would certainly have the power, but the aerodynamics and stability at those sort of speeds is a different matter.

If it really was tht easy i think we'd see alot more cars breaking the 230/240 barrier

[RC45]

Originally Posted by mindgam3 Originally Posted by RC45 Originally Posted by sameerrao Is it possible to substitute 6th gear with a more direct gear with higher gearing ... do you know if anyone has done it ... Would be interested to see the top speed then There was a gent from the Chicago area that used to post on the Z06 forums - he had a custom ratio'ed transmission in his 900hp+ Viper that he was building specifically for top end and 1/4, 1/2 and 1 mile runs. I have always thought that after a $30,000 engine swap a $10,000 custom ration transmission would be the perfect mod. With a taller rear end, and closer raitos like the Macca F1 even a 750hp Vette would surely be able to run to 250mph+ (considering the LPE 427TT already runs to 220ish. it would certainly have the power, but the aerodynamics and stability at those sort of speeds is a different matter. If it really was tht easy i think we'd see alot more cars breaking the 230/240 barrier

Actually it is that easy.

Withness the number of 200mh++ Turbo charged Vtees and Vipers.

They all run to way over 200mph with the stock transmissions - they just run shorter rear ends to get a usable 6th - they may just not make it to 200mph in under a mile....

The Viper and the Vette are plenty aerodynamic enough...

[mindgam3]

as i said, if it was that easy we'd see a lot more supercars going at those sort of speeds And a vaguely aerodynamic shape doesent neccesarily equal stability, theres lots of underbody work that provides stability n unless you have a windtunnel makes it fairly hard to tidy up the underneath of a vette or viper.

Having said that, im willing to be proven wrong

[BADMIHAI]

With a taller rear end, and closer raitos like the Macca F1 even a 750hp Vette would surely be able to run to 250mph+

"Able to" does not equal "doing it". Did you see that Mercedes CLK GTR fly at LeMans?

[sameerrao]

Originally Posted by mindgam3 as i said, if it was that easy we'd see a lot more supercars going at those sort of speeds And a vaguely aerodynamic shape doesent neccesarily equal stability, theres lots of underbody work that provides stability n unless you have a windtunnel makes it fairly hard to tidy up the underneath of a vette or viper. Having said that, im willing to be proven wrong

I read about some Lingenfelter Vettes hit 200 mph in the past - I dont recall any aero issues though some of them had engine/clutch issues as might be typical to tuned cars...

You can lay the same issue at the doorstep of RUF and other tuners as well. The Rturbo may be stable at 180mph or less but after that is it certain that it can handle 205 mph?

And remember the Mclaren has a instability window also in the 200 mph + category (I think between 210 and 220) but it is smooth before and after that.

I guess the SLR might be the most stable with its weight distribution...

All this is academic because it is rare that you will be do a sustained 200 mph anyway unless you work at the Nardi track.

And GM have the technical knowhow to get the aero done as they have high speed experience with the C5-Rs

For most people 200 mph is just a bragging right.

Even on the 'Bahn the realistic top speeds are around 140 mph.