Air compressors, CFM or Duty Cycle??

Looking at upgrading my air compressor for the new 33's. I like the Viair units but not sure which spec is more important for my use, filling tires and running a ARB.

The 400H/P has a CFM of 2.6 but a duty cycle of 33%, where as the 450H/C has a 1.66 CFM but a 100% duty cycle. I'm thinking the more CFM would be better.

My current compressor is the 200P with a 1.94 CFM and a 20% duty cycle, it works well for my 31's but is a bit slow and does tend to heat up and slow down after about three tires and will shut off after 5-6 31's(mine and buddies).

Sounds like 100% duty cycle would work better for you. 33% on these is 15 on, 30 cooldown. If you're airing your buddies then you should really consider the 100% models.

Get the higher CFM unit to fill your tires more quickly and sell your current unit to one of those "buddies" who've been sponging off your air. That way you're all done more quickly (and you first!).

I don't always have to do my buddies tires, just every now and then. So I was thinking the more CFM would be the way to go. My 20% DC will run for 20-25 minutes before shutting off, just slows way down.

do you have AC and want to keep it? converting the stock Sanden compressor is cheap, easy, and works real well.

I still have my roof, so yeah, AC stays. I've thought of adding a engine drven compressor under the hood but right now it's easier for me to get the electric. I have enough stuff to make.

There a compressor I found online that seems to offer both CFM and Duty Cycle. Check out the Maxair 4 at 4x4rockshop.com......any input??
Looks pretty good to me. Smaller than the Viair 550 with more CFM. Both are 100% duty.

Another option is to get a portable tank and fill it up before you go out. Use that when ever your compressor goes weak, for about 20 bucks I got an 11 gallon tank from homedepot. One tank with 125psi could get my 33s from 12 to 25 psi in about 2 minutes.

Weasle if you search around, there is a thread on adding a second Sanden (keeping the A/C) to use as an air compresser. The only draw back is finding a new location for the battery. If you wanted to go that route.