I know I am not a mechanical engineer or anything (though I am going to go to collage to become one) but it seems to me that an IRS would only really help on uneven surfaces. I mean if you think about it, the rest of a time it would seem that a live axle would be comprable. For all the added weight and a comprablye system I don't see why everyone is making such a big deal. If you know the basics of how both a like axle and how an IRS works my thinking seems to make sence. The live axel is a srait bar that keeps the boh wheels at the same angle. This angle is about perpindicular to the road, so as long as the area on the road from outside tip of one tire to the outside tip of the other tire you sould have great grip and good handeling. The IRS on the other hand allows the wheels to be at diffrent angles relative to each other. So it would seem that this setup would only have a real advantage on roade whear the it is a diffrent angle under each tire. Keep in mind a slight diffrence in angle such as that of normal streets would not really affect the setup that much. Not to menchon the added duribility and ability to withstand more power of the live axle setup .Now that I spoke my mind please correct me if I am wrong, just in a polite way.
With that said I started this topic to hear everyones opinion on the topic so. . .

 

You have to do some additional research on solid axle vs IRS. There is a big difference in handling, response, and ride comfort. And not just on uneven pavement.

 

The problem with live axle is that both sides are always connected, so whatever happens to the right, always affects the left to some degree, and vise versa.

A live axle also has more "unsprung weight," which means it cannot react as fast as an IRS setup when it comes to road imperfections.

However, live axle is best when drag racing.

 

For day to day driving on a high horsepower (say 400+) car I think I would prefer a good live axle design. IRS has no real advantage in handling, but depending on the road surface it may -feel- like it does. And even a well built IRS has problems with wheel hop, which is why I would prefer a good live axle with a high horsepower car. If I had to choose between an old four-link live axle and IRS, though, I'd probably take the IRS .

 

Sorry, it is bullpoo that IRS has no advantage in handling. The unsprung weight difference and nature of "INDEPENDENT rear suspension" means that there's a real advantage. It might not be enough for you; and that's valid. It might not outweigh the tradeoffs; that's valid too. But hit a bump/hole while in a turn, or lots of separations on a freeway while making a sweeping turn (quickly) and the faster response time of IRS and lower weight, matters. Again, on a track, or in a straight line (1/4), who cares. It might not be worth the fragility. But I don't like flat earthers, holocaust deniers, or people that pretend that IRS doesn't matter at all.