Going from NJ to FL in a couple of weeks. Ever since I got the Xcal II I've been running the 87 perf tune. I've heard people claim they got better milage on the 93 octane tunes. I have an Expy with 2 adults and 4 kids, fully loaded with luggage (roof top carrier & hitch-haul). Should I run the 93 tow tune or the 93 perf tune? Hopefully someone with experience can chime in.

 

I wouldn't use the tow tune unless you are pulling more than about 3000 lbs.

 

I ran the 93 perf tune last time I went on a road trip (Across IL and IA) the only problem I had was when I stopped for gas some stations don't carry 93 octane. Luckily I had my handheld with me so I was able to change my tune back to a 87 perf. If you know there will be 93 octane iI would go with it, otherwise back it down to the 87 perf tune. Have a safe trip!

 

93 performance will get better mpg you will be using less throttle to maintain the same speed if you use 87 performance. Passing is better and so is drivabilty. If you use cruise control you will probably notice less downshifts on hills.

 

I've been to FL and back quite a few times, so I know I can get 93 octane easily.
My main concern was running the 93 perf with all the extra weight. An Expy weighs more than a pickup to begin with, then add six people and all that luggage. Mike squeezes every last ounce of HP out of his tunes, so I didn't know if I'd have excessive pinging on the perf tune as compared to the towing tune.

 

I wouldn't say he squeezes every last hp out of it on a mail order tune. thats what dyno tunes are for. There is probably a degree or 2 less than timing than you could probably run taken out of your tune. The problem with too much weight wouldn't be pinging. It is that he runs it on the leaner side of things in the upper rpms so when you are towing excessive weight and you can not pull it in O/D then it is making it work that much harder and hotter. In the tow tunes it is richer as it keeps the EGT's down when you are towing for an excessive amount of time.

 

correction- he squeezes every last ounce of safe power out of a vehicle