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I was just wondering, If a probe and a mx-3 both had a KLZE swap properly done, which one would be faster?
Either from a theoretical or experienced point of view?

Cheers

Sasa

Same power, same gear ratio, they would both be just as fast and max out at ~240km/h, but the Mx-3 would accelerate faster because it's lighter.

So you're wondering if a car that's about 350 lbs lighter than another, both with the same engine and tranny gearing, which would be faster? Did you have any basic physics in Jr. High science class?

maybe he didnt know the difference between the 2 it wasnt the smartest question byt u dont gotta be such a mean prick about it

fieromx3 wrote:maybe he didnt know the difference between the 2 it wasnt the smartest question byt u dont gotta be such a mean prick about it

Lol thats what he does Lol.

Nd4SpdSe wrote:Same power, same gear ratio, they would both be just as fast and max out at ~240km/h, but the Mx-3 would accelerate faster because it's lighter.

Actually, the Probe would have a slightly higher theoretical top speed because of its slightly taller stock wheel/tire combo...

how would the tire size affect top speed....gear ratio's affect top speed....

LooseChangeRacing wrote:how would the tire size affect top speed....gear ratio's affect top speed....

Because your have the main gear ratio (1-5), then the final drive, and the diameter of the Rim/tire is the final gearing.

The probe and MX-3 use the same trannies, but because of the tire size the top speed would differ by about ~10-15 mph. The Mx-3 tops out at ~140 MPH, i have done it many times.

My friend has a ZE in his probe, and i have one in my MX-3, and we pretty much have the same bolt-ons, and there is no comparison. The Mx-3 is alot lighter...plus mine weighed in at ~2240 lbs, and his was ~2760 lbs

Here's how it works:

Your engine turns at a certain speed, for this example, we'll say it is turning at 7,000 rpm.

The Probe GT and the MX-3 GS both have a 4.39:1 ring & pinion, and a 0.80:1 fifth gear ratio. You would then multiply both numbers together, and then divide your engine RPM by the result to get how many rpm your wheels are turning:

• Engine RPM / (Ring & Pinion x Gear Ratio) = Wheel RPM
  
  7000 / (4.39 x 0.80) = Wheel RPM
  
  7000 / 3.512 = 1993 RPM at the wheels (approx.)

So your wheels are turning 1993 times per minute. How FAR you travel in that one minute is determined by the rolling circumference of your wheel/tire combo.

The rolling circumference in millimetres (mm) can be calculated like this:

• ((Tread Width * Aspect Ratio * 2 sidewalls / 100) + (Wheel Diameter in inches * 25.4 mm per inch)) * Pi = Rolling Circumference in mm
  
  For the MX-3 GS's stock 205/55-15 package:
  
  (205 * 55 * 2 / 100) + (15 * 25.4) * Pi
  
  (225.5 + 381) * Pi
  
  606.5 * Pi = 1905.38 mm (approx.)
  
  For the Probe GT's stock 225/50-16 package:
  
  (225 * 50 * 2 / 100) + (16 * 25.4) * Pi
  
  (225 + 406.4) * Pi
  
  631.4 * Pi = 1983.60 mm (approx.)

So there is a 4.1% difference in the rolling circumference of the tires, meaning the Probe GT will travel 4.1% further in the same amount of time at the same RPM with the same gearing.

To put this in more easily comprehended numbers:

• Wheel RPM x 60 = Wheel Revolutions Per Hour
  
  1 kilometre (km) = 1,000,000 millimetres (mm)
  
  So...
  
  1993 x 60 = 119,580 Wheel Revolutions Per Hour
  
  119,580 x 1905.38 / 1,000,000 = 227.85 km/h (approx. 142.4 mph) for the MX-3 at 7,000 rpm with 4.39:1 ring & pinion and 0.80:1 fifth gear
  
  119,580 x 1983.60 / 1,000,000 = 237.20 km/h (approx. 148.25 mph) for the Probe GT at the same rpm with same gearing

Of course, this is totally leaving aside the relative aerodynamics of both vehicles, but hopefully this helps clarify things for you!

I should also note that the MX-3's shorter wheel/tire combo will also increase the torque it puts down to the ground vs. the Probe by approximately the same amount (around 4%) due to the shorter wheel/tire combo effectively giving the MX-3 shorter gearing.

When you combine the fact that the MX-3 is hundreds of pounds lighter with the fact that it will actually put more torque to the ground than the Probe, when it comes to acceleration (assuming no traction issues and equally good launches) there will be no comparison...

93_mx3_gs wrote:

fieromx3 wrote wrote:
maybe he didnt know the difference between the 2 it wasnt the smartest question byt u dont gotta be such a mean prick about it

Lol thats what he does Lol.

LOL

lakersfan1 wrote:So you're wondering if a car that's about 350 lbs lighter than another, both with the same engine and tranny gearing, which would be faster? Did you have any basic physics in Jr. High science class?

If 10 lb and 15 lb bowling balls are released from the same height at the exact same time, which will hit the ground first

FlyVFR wrote:

93_mx3_gs wrote:

fieromx3 wrote wrote:
maybe he didnt know the difference between the 2 it wasnt the smartest question byt u dont gotta be such a mean prick about it

Lol thats what he does Lol.

LOL

lakersfan1 wrote:So you're wondering if a car that's about 350 lbs lighter than another, both with the same engine and tranny gearing, which would be faster? Did you have any basic physics in Jr. High science class?

If 10 lb and 15 lb bowling balls are released from the same height at the exact same time, which will hit the ground first

Both. It's gravity which carries things at roughly 120 MPH evenly. from like 50 feet or whatever. Driving force will be the same no matter the weight. Impact force however will be far different.

Tatsu : Good explanation =) props.

tatsu wrote:Of course, this is totally leaving aside the relative aerodynamics of both vehicles, but hopefully this helps clarify things for you!

How about the torque factor/difference to turn the diferent diameter tires?


EDIT: Oooops. I see you already posted the answer right after the first post above...Did not see it when I posteded above...

93_mx3_gs wrote:Both. It's gravity which carries things at roughly 120 MPH evenly. from like 50 feet or whatever. Driving force will be the same no matter the weight. Impact force however will be far different.

Well OK then. I was just wondering how Lakers1 would answer it

Slammed6 wrote:

LooseChangeRacing wrote:how would the tire size affect top speed....gear ratio's affect top speed....

Because your have the main gear ratio (1-5), then the final drive, and the diameter of the Rim/tire is the final gearing.

The probe and MX-3 use the same trannies, but because of the tire size the top speed would differ by about ~10-15 mph. The Mx-3 tops out at ~140 MPH, i have done it many times.

My friend has a ZE in his probe, and i have one in my MX-3, and we pretty much have the same bolt-ons, and there is no comparison. The Mx-3 is alot lighter...plus mine weighed in at ~2240 lbs, and his was ~2760 lbs

The Mx3 will surpass 140. Ive rode in 2 MX-3 ZE's and hit 150. I havent tried in mine yet, I'm going to get some good suspension 1st.