Sunir

wow fantastic! Marcin way to go buddy!

Gondon

Let me go off-course for a second and discuss top speed, not the Texas mile.

Tom, are you saying the gearing is limiting the top speed of the vehicle?

If the CLK63BS top speed is 199 and it hit 161 on the mile...

Can I assume this CL65 can easily go to 240+? Or its limited somehow by its gearing?

blackbenzz

You can only go as fast as your gearing allows you (assuming you have the power, etc to get there). You can raise rev limiter to increase max speed or alter tire height to alter final gearing as well

Gondon

Ok, Thank you

Because a stock CL65 can hit 200mph I believe, this one will just do it 50 CL ahead lol

Sunir

Any car can hit top speed given they have enough distance to do it and are not impacted by catastrophic failure. This said any given car is limited in it's speed by it's gearing, so as Ahmad said if you make the power you will go as fast as your gearing lets you, that's the governance. One of the things these standing mile cars have to do is optimize gearing specifically for the range of 1 mile (taller gear) allowing them to utilize their power most effectively in accordance with the gearing...same is true for 1/4 mile cars - they would benefit from optimizing gearing for that distance (ussually a shorter gear). Hence a car optimized for the standing mile would not be optimized for 1/4 mile and vice versa...as Marcin told me once on the phone during a fairly long conversation on dynamics and automotove theory - "Know what you want to do, identify a purpose before spending any money or undertaking any build/project"

TMC M5

From a theoretical standpoint, there are a number of factors that go into this. The rear gearing, the transmission gearing, tire size and RPM capability. The V12TT powerplant is a relatively low revving engine. If you moved the redline up 200RPM, you could see another 7 mph if all else remained static.

But to answer your question, no a stock geared CL65/SL600 would never see 240 mph.

I was going to try to use a Bugatti Veyron as an example but its tire sizes are completely unique and I can't convert the diameter. Let's use a Ferrari Enzo instead. A Ferrari Enzo has a 4.10 rear gear, but also has relatively tall tires (345/35/19's= 28.51") and a tall 6th gear (.76). The Enzo's added advantage is its ability to spin to 8K RPM. This allows for the Enzo to attain a theoretical top speed of 218mph.

You can play around with tire sizes, gears on this useful website:

http://www.fatboyraceworks.com/gears...raph&Compare=1

Edit: For some reason the tire size keeps defaulting back to 23.44" instead of the 28.51" on the link above... oh well...

Tom

Marcus Frost

Sunir not to be disrespectful but if by top speed you mean it's "geared top speed" that is not correct. Many cars cannot hit the top speed they are geared for typically because they simply do not have enough horsepower, and obviously as speed increases so does resistance.

The Dodge Viper, for instance, has a very low 6th gear (mostly for MPGs) - which gives it a very high top speed, gear wise. However in stock form, the car actually will reach it's highest potential top speed in 5th.

-m

Sunir

good point Marcus...true...I should have mentioned that the 2 assumptions were that the given vehicle had the power to support it's gearing which were to me maximized for a given situation and also be able ot overcome resistance at high speeds (for example aero considerations)

thanks for pointing that out Marcus

TMC M5

What is funny is that at lunch I was checking out a news stand. I ran across an issue of Mopar magazine which had a top speed shootout between a an LMC '70 Cuda with a Viper twin-turbo V10 (1,500hp) against a stock Ferrari Enzo. The Cuda was running the standard T-56 gears with a 3.08 final drive (I think it's 5th gear is .50 ) . I believe the car hit 208mph around an almost 5 mile oval. It could have gone faster but the car was too unstable. The Ferrari Enzo on the other hand...hit its 218mph top speed without any drama.

I actually just found a video of the test:

http://www.rideschannel.com/componen...ube/video/7481

My apologies for going off topic...but I thought this was pretty interesting..

Tom

Marcus Frost

Tom I saw that video too, and it's a very good illustration of not only power, but the real engineering that goes into making a car capable of doing high speed. There are much more "reasonable" examples such as your average 150hp car, which gearing wise could hit a fairly high speed, but due to the lack of power would not be able to get there.

While we are sharing funny stories... one of the scariest things I remember doing a high speed run years back happened in a Dodge Viper GTS. The car was heavily modified, and in spite of the rumble and grumble going through the gears, at 180mph the car makes a very loud and frightening POP noise. Why does it make that sound? At 180mph there is such a vacuum created behind the side view mirrors, that it actually pops them back into the folded position. I was not aware of this and man, hearing a loud, almost tire-pop like sound at 180mph is enough to make anyone check their pulse for a split second.

It was an "interesting" experience.

-m

soulsearcher

Hmmm...210 in the mile...not sure about that one. I have a new found respect for what it takes to get these lead sleds (all 4600-4700 pounds) to 200. The 210 mark in the mile would take an insane amount of extra power but who knows.

As for top speed; The car has an amazing amount of power left at near 200 and we may (not sure yet, since a crate motor is 40k if we crack the block which is a real possibility at these numbers) raise the redline to 6500 which would allow us 228. I think, the car has enough power to hit that, given an extra mile....stay tuned.

TMC M5

Check your pulse?!?!? I would be checking my pants...

Tom

TMC M5

228 mph sounds about right for a 500 RPM increase in the redline. But I agree it could take a bit more space. Especially given the gearing of the car.

Maybe with the roll cage installed, you can pass the stupid tech inspection for the ECTA (East Coast Timing Assoc) and do the Loring event in Maine. That one has the 1.5 mile run.

Tom

Goni C63

very impressive !!!!

mthis

whoa congrats that is very very impressive.


Mo who got close to 188 on a c63, from whats going around the W204 DADc63 is at 180.XX em i missing someone?