VIAIR 300p vs VIAIR 400p

Eddie Greenlee

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Just wondering if the Viair air compressor 300p is as good as the Viair 400? Or should I spend the extra$ on something else?! I found the 300p on sale for $100.00
 
There are a million different viair compressors, you really have to look at the exact model numbers with the letter to compare. Duty cycle is really important. If it's cheap and works you're probably good. Keep in mind some used viair units have served hard lives in air suspensions already, I don't know if you are talking new or used.
 
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There are a million different viair compressors, you really have to look at the exact model numbers with the letter to compare. Duty cycle is really important. If it's cheap and works you're probably good. Keep in mind some used viair units have served hard lives in air suspensions already, I don't know if you are talking new or used.
She said she used it 2 times. B000X90YUO is the model number . and that they are going a different route
 
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I have a Viair 400P portable that I have owned for several years and a Viair 400H that I hard mounted in my LJ in 2018.

If you will never air up tires larger than 31-32" then the Viair 300 will suffice. It will do 33's, but a bit too slowly for my tastes. To be fair, there are many Viair 300's out there airing up 33" tires without issue. A Viair 300 would not be adequate for 35's.

The Viair 400 handles 33" tires well and I have had zero issues airing up 35's with my two Viair 400 compressors.

Personally, I think the Viair 400P is one of the best buys in portable 12v compressors if you can get one in the $160 price range where it is often priced on Amazon Prime. I would definitely spend the additional $50 to get a 400 over a 300 series.

Added on edit: I do not think the Viair 400P-Automatic or 400-RV kits are particularly good buys for a jeeper whose primary interest is airing up his/her own jeep tires. You don't need the automatic shutoff between tires if you use an open chuck which renders the additional expense for that feature no particular bargain. I also experimented with a Flexzilla 1/4" hose and closed chuck and had plenty of time with the 400P to get from tire to tire with pressure building up in the 300 psi rated hose without doing any damage to anything - even when I purposely delayed several minutes between tires. The basic 400P kit is plenty.

________________________
PS - Don't be too concerned about duty cycle if you get a 400P. You will be finished airing up your tires and can air up all four of a buddy' tires as well before you will get to the 20 minute run time "limit" of its 33% duty cycle. Even if you are airing up 35's. If you compare the specs of Viair 400P with 33% duty cycle and a Viair 450 with 100% duty cycle, you will see that the trade off for longer duty cycle is less CFM. I have found that for me, favoring increased capacity (speed) over duty cycle has been the better choice because I am seldom tasked with airing up other people's tires and I have no need to run a compressor continuously for long periods. YMMV
 
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I have them installed on both of my rigs, never used them for it but had few times helped some elder drivers needing air (for a pretty lady once :) ). They come pretty handy during winter as well for most of the gas stations air pump does not work.
 
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I have a Viair 400P portable that I have owned for several years and a Viair 400H that I hard mounted in my LJ in 2018.

If you will never air up tires larger than 31-32" then the Viair 300 will suffice. It will do 33's, but too slowly for my tastes. A Viair 300 wouldn't be adequate for 35's.

The Viair 400 handles 33" tires well and I have had zero issues airing up 35's with my two Viair 400 compressors.

Personally, I think the Viair 400P is one of the best buys in portable 12v compressors if you can get one in the $160 price range where it is often priced on Amazon Prime. I would definitely spend the additional $50 to get a 400 over a 300 series.

Added on edit: I do not think the Viair 400P-Automatic or 400-RV kits are particularly good buys for a jeeper whose primary interest is airing up his/her own jeep tires. You don't need the automatic shutoff between tires if you use an open chuck which renders the additional expense for that feature no bargain. I also experimented with a Flexzilla 1/4" hose and closed chuck and had plenty of time with the 400P to get from tire to tire with pressure building up in the 300 psi rated hose without doing any damage to anything - even when I purposely delayed several minutes between tires. The basic 400P kit is plenty.

________________________
PS - Don't be too concerned about duty cycle if you get a 400P. You will be finished airing up your tires and can air up all four of a buddy' tires as well before you will get to the 20 minute run time "limit" of its 33% duty cycle. Even if you are airing up 35's. If you compare the specs of Viair 400P with 33% duty cycle and a Viair 450 with 100% duty cycle, you will see that the trade off for longer duty cycle is less CFM. I have found that favoring increased capacity (speed) over duty cycle is the better choice unless one is regularly tasked with airing up several people's tires or if one has some other need to run a compressor for an hour at a time.
excellent information Thanks!
 
I have them installed on both of my rigs, never used them for it but had few times helped some elder drivers needing air (for a pretty lady once :) ). They come pretty handy during winter as well for most of the gas stations air pump does not work.
would ya happen to have a picture or two?
 
I have a Viair 400P portable that I have owned for several years and a Viair 400H that I hard mounted in my LJ in 2018.

If you will never air up tires larger than 31-32" then the Viair 300 will suffice. It will do 33's, but too slowly for my tastes. A Viair 300 wouldn't be adequate for 35's.

The Viair 400 handles 33" tires well and I have had zero issues airing up 35's with my two Viair 400 compressors.

Personally, I think the Viair 400P is one of the best buys in portable 12v compressors if you can get one in the $160 price range where it is often priced on Amazon Prime. I would definitely spend the additional $50 to get a 400 over a 300 series.

Added on edit: I do not think the Viair 400P-Automatic or 400-RV kits are particularly good buys for a jeeper whose primary interest is airing up his/her own jeep tires. You don't need the automatic shutoff between tires if you use an open chuck which renders the additional expense for that feature no bargain. I also experimented with a Flexzilla 1/4" hose and closed chuck and had plenty of time with the 400P to get from tire to tire with pressure building up in the 300 psi rated hose without doing any damage to anything - even when I purposely delayed several minutes between tires. The basic 400P kit is plenty.

________________________
PS - Don't be too concerned about duty cycle if you get a 400P. You will be finished airing up your tires and can air up all four of a buddy' tires as well before you will get to the 20 minute run time "limit" of its 33% duty cycle. Even if you are airing up 35's. If you compare the specs of Viair 400P with 33% duty cycle and a Viair 450 with 100% duty cycle, you will see that the trade off for longer duty cycle is less CFM. I have found that favoring increased capacity (speed) over duty cycle is the better choice unless one is regularly tasked with airing up several people's tires or if one has some other need to run a compressor for an hour at a time.
would ya happen to have a picture or two?