Hey guys newbie here. i see some posts (not that i can find at the moment) about guys that have changed the gears in their cars. are they refering the the rear, or final drive gear, or is this the same bc most final drive gears are 1:1 right? if anyone could give me some direction i would appreciate it. Also what site would be good fin find info/products. thanx in advance.

 

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www.ricks2k.com

 

I think you would benefit greatly if you did some homework by reading up about this subject at places like "How Stuff Works". You seem to not quite understand this whole concept of what these "gears" are.

The S2000 is a rear wheel drive car. It has a rear differential (or "pumpkin"). Refering to the "rear" and "final drive" is the same. It is a ring and pinion set that is being talked about. This is what you buy.

No. Most final drive gearing would be in terms of 4.10:1 (stock S2000). You, yourself, put this in your title so I'm not sure why you would suddenly start thinking about it in terms of 1:1. Generally speaking 1:1 is what happens in the top gear - for every revolution of the engine, you get the same revolution of the drive wheels. Traditionally, this would occur in 4th gear. This gear was refered to as "direct drive". Now, we have "overdrive" gears like 5th and 6th, which become our "top gear".

As stated, 4.57 (now 4.56) is only available from Rick's (board sponsor). The other ratios can be found as Mazda parts or "J's" parts.

Also, to help you understand this further, you should do some investigation into just how such gears will change the way your car drives in terms of speed in each gear, top speed, etc. The following should be good reading for you:
http://www.turnzero.com/technical_resource...gear_calculator
https://www.s2ki.com/forums/showthread.php?s=&threadid=85687

Also, go to the top of UTH and then to the top of "Technical" and you will find a stickied thread with "FAQ's". There is a section in there devoted to threads about "gears".

 

Hm. According to the aforementioned "Gear Calculator" the maximum speed-by-gear for model years 00-03 is listed as follows: 1st gear - 42.8 mph; 2nd gear - 65.6 mph; 3rd gear - 90.6 mph; 4th gear - 115.5 mph; 5th gear - 138.1 mph; 6th gear - 165.4 mph while the '04, '05 and '06 model years are listed: 1st gear - 36.9 mph; 2nd gear - 56.5 mph; 3rd gear - 78.0 mph; 4th gear - 99.5 mph; 5th gear - 121.5 mph; and 6th gear - 151 mph.
Might this rather substantial disparity be given to the increased engine-size and thus H.P. in the '04, '05 and '06 models?
Thanks in advance.


Peace,
Guy

 

Keep in mind that BOTH cars will only do a max of about 150 mph anyway. One because it is drag limited and the other is because it is gear limited (and drag limited). In either case, it happens to be about the same speed. Don't let the gear calculator fool you into thinking that one car can go faster than the other. It can't.

The AP2 can actually reach it's drag limited top speed because it is geared to do so. The AP1 can't reach it's geared top speed (165).

Remember that the AP2 ('04 and up as you call them) has a different secondary reduction gear at the back of its transmission and different ratios for 5th and 6th gears, too. It also has 1000 rpm LESS at redline. All of this allows it get near its redline in 6th, which just happens to be about the same speed as an AP1 can get to because of drag.

 

I see. Thank you, xviper.
I suppose I understand the meaning of "gear limited," but what might "drag limited" mean? And what lies behind the designations "AP1" and "AP2"?

Thank you again, xviper.

 

It takes a specific amount of HP and torque to move a car through the air along the ground. This of course is affected by the car's aerodynamics, rolling resistance of tires, etc. Every car reaches a critical speed where the power it has can not longer make it go any faster due to the aerodynamic "drag" that it must over come. This is what is refered as a "drag limited" top speed. Once you get up to a car's max speed, it take an exponential increase in HP to increase speed arithmetically.
A car's top speed will be limited by either its geared limit or its drag limit, whichever is lowest. The AP2 seem to have the ideal compromise as both these limits are about the same.

AP1 is the designation for S2000 with the 2.0L engine and 9000 rpm redline.
AP2 is the designation for S2000 with the 2.2L engine and 8000 rpm redline.
You can see this designation as part of your VIN.