[Fast Ken]

Just for fun I would like to calculate the top speed in 1st thru 6th (unattainable I know). But I am missing the tranny gear ratios needed to plug into the formula. Where is that posted?

Also what is the rev limiter set at exactly? Is it 6700 rpm?

And does anyone know what does limit the rpm? Is it fuel management or ignition or timing?

KEN

[vtirocz]

See table below comparing the SS to SS 1LE (only difference is slight rear tire diameter difference)

[Fast Ken]

Excellent. However, when I used the ratios and calculated the mph based on TireRack's 767 revs per mile for the GY Supercar 3 tires the results were about 3% less mph. I'm sure tire loading and deflection would be the biggest factor in making for these differences.

Does anyone know what technology is used for limiting the rpm?

[s346k]

you have the car. you can get 1-4 in a single pull.

[arpad_m]

Originally Posted by Fast Ken

Excellent. However, when I used the ratios and calculated the mph based on TireRack's 767 revs per mile for the GY Supercar 3 tires the results were about 3% less mph. I'm sure tire loading and deflection would be the biggest factor in making for these differences.

Does anyone know what technology is used for limiting the rpm?

There are several limiting methods in place, extreme fuel cutoff is indeed at 6700 rpm on the SS.

[vtirocz]

Originally Posted by Fast Ken

Excellent. However, when I used the ratios and calculated the mph based on TireRack's 767 revs per mile for the GY Supercar 3 tires the results were about 3% less mph. I'm sure tire loading and deflection would be the biggest factor in making for these differences.

Does anyone know what technology is used for limiting the rpm?

Good catch. My calculation assumed the tire was perfectly nominal with no deflection under load, which is not accurate. Using a manufacturer's (or tested) rev/mile # should be more accurate.

"Revolutions Per Mile
Revolutions per mile indicates the number of times a tire revolves while it covers the distance of one mile. Depending on the tire manufacturer, revolutions per mile may be either measured in a laboratory or derived from calculations based on their previous test experience.

Tire revolutions per mile cannot be calculated by simple math because the tire tread and sidewall bend and stretch (deflect) when the load of the vehicle presses the tire against the road.

Since the resulting loaded or rolling radius is less than half the tire's published overall diameter (which would only reflect the tire's unloaded radius), calculating the tire's absolute rolling circumference isn't possible.

Additionally, a tire transitions from an unloaded to loaded state as it rolls, continuously flattening where the tread footprint comes into contact with the road. These continuous transitions result in some tread slippage, again increasing the tire revolutions per mile beyond what simple math would indicate."

I've corrected the table for the SS 1LE below.

[Scargoes]

According to the CAN BUS data, 4th gear at 6372rpm the vehicle speed is 136.76mph. This was on OEM sized Supercar 3 tires. the GPS data on the secondary data logger backs up the speed reading.

[wnta1ss]

Based on data that I have seen for these tires, I have an estimate for your 1LE. Data shows that the stock speedo calibration is off and also that the rating from tire rack is off, the truth is somewhere in between.

1st=52.04mph@6500rpm
2nd=77.77mph@6500rpm
3rd=106.49mph@6500rpm
4th=138.43mph@6500rpm
5th=187.07mph@6500rpm
6th=276.87mph@6500rpm

While the rev limiter says 6700rpm in the stock tune, my own SS when it was stock would just stop at 6500rpm on the tachometer. So I don't know what your car will actually allow, but of course you can try it. Besides the rpm limiting methods previously mentioned, the computer can and does close the throttle.

As far as the unattainable speeds, this model can actually reach around ~6k in 5th gear, and that would be your top speed gear. This info comes from a 2.7 mile test where the stock 1LE reached 172mph (174 on speedo) and also one that with just the GM CAI and tune added reached 175 on the speedo in a long run on the autobahn.

[JT Camaro]

ive alwasy wondered this for the ZL1 1LE but cant find the ratios posted

[arpad_m]

Originally Posted by JT Camaro

ive alwasy wondered this for the ZL1 1LE but cant find the ratios posted

https://www.camaro6.com/forums/showt...3#post10866513

[JT Camaro]

Originally Posted by arpad_m

https://www.camaro6.com/forums/showt...3#post10866513

Thanks man! Not sure how I missed that thread.
Now I'm curious how the auto stacks up

[JSH]

Speed and rpm per gear will vary from car to car, build to build, location to location