There is certainly a difference between the RWD and the Sport Coupe.

If you go to Infiniti USA eStore, type in a VIN number from the sport package rwd sedan AND the VIN number from the regular/non sport rwd sedan it is the exact same part number for the rear sway bar. Both the regular rwd sedan and the sport rwd sedan rear sway bar is the same.

The true sport rear sway bar is the coupe sport rwd. If you type in a rwd sport package coupe that gives you a completely different part number for the rear sway bar compared to the part number of the sport and non sport sedan.

Also, the strip of paint on the regular rwd sedan and the sport rwd sedan has a strip of white paint, the strip of paint of the awd has a strip of orange paint, and the strip of paint on the sport coupe has a strip of blue paint.

So to conclude:

rwd sport sedan and rwd non-sport sedan= same rear sway bar

sport rwd coupe= different from the rest.

Now, I do not know what the difference is, but I do know there is a difference. I just hope the rwd sport coupe rear sway bar is not too stiff that my rear-end of my awd will start swinging during regular driving in snow, slow regular driving.

 

If anyone is interested im selling my oem IPL sway bars.
Pm me

 

Thanks for the site reference. Do you know where the IPL Convertible sways would fall in that spectrum? I notice that they are $20-30 less than the equivalent sport sways

 

why not just go with hotchkiss?

 

I do not know where the IPL Convertible sway plays into it. I do know when I type in a VIN number for the rwd sport coupe that it pulls up the IPL coupe rear sway bar. So, I believe the rwd sport coupe= IPL coupe rear sway bar.

 

My ipl rear has the blue line but different numbers than the coupe and is fs too.

 

I'll let you know when I install my 370Z sway bar lol (the same as the G37S Coupe). It's due to arrive tomorrow evening

Got for $40 + shipping off eBay

 

I just went to Ebay and pulled up a rear sway bar for the 370Z and I believe that is the same as the base G37. The strip of color in the middle of the bar is a whitish color which is the same as the G37 base bar. The G37 sport coupe bar has a strip of blue as the color.

This is like the one that I bought:
http://www.ebay.com/itm/08-13-Infini...RXsnM5&vxp=mtr

See the blue strip of paint in the middle.

 

Your description on the handling makes sense - it's a tad more likely to oversteer or slide bouncing over a bump. I doubt getting the RWD base sway would make a significant difference, since from what I've read, they are the same diameter but the bar itself is little more dense (more material = stiffer).

In regards to questioning if the stiffer RSB would make the front give up more than the rear end, I can't answer that until my RSB is installed. My guess is that you're feeling a difference with the steering weight in corners since not as much weight gets loaded on the front tires.

In my experience with the stock setup, the steering can get overwhelmingly heavy if you corner hard. This is likely because while the car rolls at the back, the front resists that. For example, if you dive into a right curve, the body rolls to the left and as you roll, the steering gets heavier with the front left taking most of that weight transfer. That weight transfer ends up being too much of a load for that tire, intitiating the understeer after turn-in. This setup relies heavily on the front tires and with a soft tire, cause the front outer tread to wear faster.

Please correct me if I'm wrong, but what the stiffer RSB does is distribute that to the rear tires, so in the same example right curve, both the front left and rear left tires handle the weight transfer more evenly. This means that the front tires may not bite as hard when you turn in, but once you are in the actual turn, the grip is more stable as both the front and rears are better working in conjunction to carry you through the turn.

In regards to your observation with the sway bars, you are definitely correct. Just like you did, I cross-checked the vehicle VIN (JN1AZ4EHXBM554774) on Parts.NissanUSA.com for the part number, then looked up the part number found (562301EA0C) on Parts.InfinitiUSA.com

There seems to be some discrepency but I believe you are right.

The RWD Sway Part # 562301EA0C comes up as:

- 2011-2012 6MT RWD Sedan
- 2013 2WD/STD

 

That's encouraging to here. Here's a new color: light pink/purple

 

Thats the same color as the base G37. In the pics it just looked white, it is the same pinkish/purple color you have. Keep us updated on how it feels after

 

Bought this the other day, and it appears to be the same light purple, we'll see when I get it next week. Should definitely be an improvement on my stock x bar.

http://www.ebay.com/itm/182253221653?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

Update on my 2011 370Z sway bar:

It should've been this way stock! Roll is a lot less substatial and steering weight is more consistent - it does not load up too quickly like prior and is much less prone to understeer.

As a result, the car is a lot more eager to turn in like it's on rails! Additionally on straight roads, lane changes no longer produce a left/right shake adding to the feel of stability. Overall, it is very neutral.

Ride quality wise, there may be a barely perceivable increase in choppiness from the rear. However, this is negligible and does not cause any discomfort.

I highly recommend this mod to anyone - it's a must do for any G37x owner not willing to splurge for a Hotchkis set.