Originally Posted by smartbomb

This should come as no surprise. The differential would fail without a cooler. Its all about airflow and diff location. The 350Z has this same problem as well. Look at the pre-production test cars we photographed and wrote up, they all had diff coolers.

The Nismo car doesn't really have a Nismo performance LSD, that is a Salisbury mechanical LSD. The Nismo 370Z has a viscous LSD, the same as the stock sports model.

Also note that the R200 diff in the 370Z is very strong and has a long history as being a durable piece that is exceedingly strong that can hold 1000 hp under racing conditions in the IMSA GTO Z and various racing GT-R's and Z's though history.

The issue is that in both the 370 and 350, there is no air circulation around the diff and it heats up. Generaly about 30 minutes of track time is about what it takes for the temp to start getting critical. GTA makes a diff cooler kit and we have all sorts of info and tips on the other site for what to do if you have a track driven car