topdaytrader

mattg

why, so you can talk shit ?

mattg

according to the 1/8 mile----->0-60 calculator my fastest 0-60 was a 5.44

on the street probably 5.8

fastest 1/4 - 14.16 @ 99.11



www.tweak3d.net/videos/calcs/sixty.shtml

I am RobG

well if i ran a 9.0 1/8th mile which is like a 13.99-14.0 and probably around 5.3-5.2ish

EricL

The FWD is not happy getting off the line...

14.2 in the quarter is close to 5.7 - 5.8 to 60.

I've done a bunch of 0..60s in 5.7 - 5.8 range with I/H light wheels/tires @ 60-degrees F. (GTECH average, same flat street, many times, two directions).

This was from a chart that Nashua posted some time ago.



LINK: http://home.earthlink.net/~tmahon281/tech.html

There are not a lot of FWD cars included in the data and, IMO, the FWD needs a penalty if not running drag slicks.


Check out the E46 M3 times for 0..60 and 1/4 mile:

http://www.m3forum.com/ubb/Forum3/HTML/000015.html

I am RobG

bro i hate to break it to you bu gtech doesn't work.

Shawn S

Do you want REAL times or ones for MAKE BELIEVE cars like you drive ???

Shawn S

EricL

Funny, I've talked to the folks over at Gtech and they have limitations. The new one – the Gtech Competition Pro at least corrects for the pitch if there aren't any bumps.

However, some people manage to get consistent results and it has a lot to do with how it's set up and who uses it. The unit when used on a level street, with no bumps will read a bit low if there is a lot of pitch up during acceleration.

So, just saying "it doesn't work" is like saying a CLS isn't fast. Fast and accurate are relative terms and some people manage to get a readings that match their ETs very closely and others get a different reading on every run.

If the unit is returning consistent results on a "flat" street, it's not going to be too far off. In the wrong hands, you can have a Pinto reading 0..60 in 2-seconds...

-END-

Chaptorial

Funny stuff.

Bluto

I know I can do 2.737 and 9.06.

You should try it.

typeR

this'll tell you how scewed there figure are ...it says 5.13 for my 0-60 based on my 8.969 1/8th mile time...however take that 0-60 figure and plug it in the 1/4 mile calc and it says i run a 13.5...obviously this is off...13.8** maybe but no chance of a 13.5 on this set up

EricL

Extrapolation of extrapolation of extrapolation -- it's not going to work well... :shakehd: :shakehd:

If they designed aircraft this way, they would have all crashed and we'd be floating around in Zepplins...

Did anyone read the following “warning” on that 1/8-mile calc page?

"1/8 mile -> 0-60

These calculators are based upon formulas circulating the Internet, that are believed to be close estimates for the average car's performance. These numbers do not mean anything in real life, but they provide a good "estimate" at best. Keep this in mind before you spill these numbers all over your favorite car forums.




That 1/4 <--> 0..60 chart that Nashua originally posted is just a "least squares regression" (or other curve fit) for a bunch of cars tested from various sources. As such, it should be used as a "rough" guess-timator.

The FWD is clearly under represented in that chart and the CLS, and other FWD cars without drags slicks and other traction aids, is not going to "get off the line" well compared to RWD and is going to be even further back compared to AWD. Ever watch Speedvision GT? Watch the S4s jump out in front of everybody at the race start! Enough said!

Look at the BMW M3 times and you'll see that the sub 5-second runs come up with 13.3-13.5.

Even the NHRA calculator page is making assumptions that will not be accounted for in a CLS.

However, as a general rule, the cars running around 14.2 with good tires and light wheels will run sub 6.0 second 0..60s.

Gtech notes:
I've already spent pages on gizmos and math explaining why and how Gtechs can give "loony" results. However, you can get an idea of how close the unit is by checking how consistent the times are on a given section of road. The road must be flat, it must be free of bumps. The unit needs a mount that doesn't wobble or move (a big problem with some of the units). IMO, if you can get a set of runs that consistently run within 0.1- to 0.2 seconds, it is close enough. If you try the unit and just try to average out a bunch of times like: 5.5, 5.8, 5.9, 5.4, etc -- it's not worth bothering to use the numbers (my comment assumes a good road with minimal wheel hop and a small pitch-up at the start).

If charts and GTECHs match and make sense, you are at least confirming and substantiating data and/or modifications and changes. Again – it’s a tool and even the new one will screw-up over bumps.

Based on your 14.0 times (and future 13..9/13.8 times), you are probably seeing mid 5 second runs to 60 MPH.

To finish and sum up the issues -- each calculator is a "rough" tool and each time you "extrapolate" the numbers and move to another assumed/derived time, you increase the error. That chart is only good enough to get a ballpark figure from 0..60 to 1/4 mile and 0..60 to 1/4 mile. It also helps to see what other similar setups are doing. Since you have one of the few 3.5Ls running around, you don't have a "twin" to compare and validate numbers to (it would help if another car was running the same setup and it was possible to look at the "spread" between slightly different Gtech 0..60s and well defined 1/4 miles times. This presumes that the times all have temps, barometric pressures, humidity, altitude, and weight loads listed to allow some "insight" into the conditions that produced the numbers).

I spent some time checking the 1/4-mile graph that Nashua posted and it misreports older muscle cars, cars with very low weight and high power-to-weight, cars with very high drag, and older muscle cars with bias-ply tires (no traction).