You are in the ballpark but reading temps after landing is extremely inaccurate. In flight temps are probably around 240-250 which should be fine.

Thanks for the response. Good to know its in the ball park! I'm installing the 55ra on my 107" decathlon. Came to know that the exhaust extension are an inch short and confined in the cowl. Given the OD of the exhaust is 20mm, it was difficult to find extension longer than 3 inches. Managed to find extensions from tower in case anyone needs one, it is not a teflon tube as the stock one's but a silicone tube for the dle 170 in 6 inches. I'm receiving it in a few days and will post the pics of the fit.