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Switched to the "blue" Riff Raff proprietary 6637 air filter

42K views 13 replies 7 participants last post by  Brandonpdx  
#1 · (Edited)
Donaldson Blue® 6637 Intake Filter - Ford 7.3L Powerstroke

I've read about these a little bit and thought I'd finally give one a shot after reading the positive reviews on their site now that they've been out a little while. I'm not one to buy into marketing claims that much, especially on something like air filters, but it seems to be an upgrade over the standard 6637 so thought I'd swap one in there. Apparently, it's supposed to flow "37% more air" over than the standard 6637. It's a proprietary filter built for Riff Raff that you can't buy anywhere else. Only time will tell if there are any noticeable "differences"- (not expecting there to be much) but just wondered if anyone else had compared the two before.

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#2 ·
Donaldson Blue[emoji768] 6637 Intake Filter - Ford 7.3L Powerstroke

I've read about these a little bit and thought I'd finally give one a shot after reading the positive reviews on their site now that they've been out a little while now. I'm not one to buy into marketing claims that much, especially on something like air filters, but it seems to be an upgrade over the standard 6637 so thought I'd swap one in there. Apparently, it's supposed to flow "37% more air" over than the standard 6637. It's a proprietary filter built for Riff Raff that you can't buy anywhere else. Only time will tell if there are any noticeable "differences"- (not expecting there to be much) but just wondered if anyone else had compared the two before.

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Maybe I’ll dyno my truck if I get a chance to go over to Orlando - provided I order one lol.


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#3 ·
I have one of these on mine also. It seems to built boost quicker than before but that could be because it's cleaner than the old one.
 
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#4 ·
I would be very interested in any before and after blue dyno numbers.

Here is my solution; significantly less smoke and faster spooling.
 

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#5 ·
Switched to the "blue" Riff Raff proprietary 6637 air filter

MeTo; said:
I would be very interested in any before and after blue dyno numbers.



Here is my solution; significantly less smoke and faster spooling.


I like your setup - again dyno b4 vs lol. Maybe when I go to the dyno you ought to let me borrow your setup so I could swap out lol. I think the guy wants $80 for three pulls - gotta check


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#6 ·
Thanks, I have had some think it's too extreme. But, the difference is significant. I would have been skeptical myself, had I not experienced the difference. The big Donaldsons filter great, but they don't flow the CFMs many think they do. From my filter research before I decided on two, the blue RiffRaff filters have wider pleats. I don't remember what the exact increase in filter media area is?
 
#7 ·
I put one on mine last weekend and tossed the regular white Donaldson that was on the truck when I bought it, since it was pretty dirty. Did I notice much difference? Hard to say since over that same weekend I replaced the water pump, added a 203* thermostat, and am now running without the fan after realizing the clutch was failed locked, so of course the truck is zippier than it was with that huge drag gone.
 
#10 ·
I put one on mine last weekend and tossed the regular white Donaldson that was on the truck when I bought it, since it was pretty dirty. Did I notice much difference? Hard to say since over that same weekend I replaced the water pump, added a 203* thermostat, and am now running without the fan after realizing the clutch was failed locked, so of course the truck is zippier than it was with that huge drag gone.
SO.....HOW ARE YOU COOLING YOUR TRUCK NOW?....

DID YOU REPLACE THE FAN WITH AN ELECTRIC ONE?....
 
#8 · (Edited)
Well, I drove around some today. The jet airliner "whine" sound from the 38R is most definitely more pronounced in the lower RPMs than it was before which is pretty cool. Difference in performance that you can tell from the seat of the pants? Nah, I really can't tell a difference.... if I were to say, I'd be concerned it would be the placebo effect. Maybe there would be a very slight reduction in EGTs, but only time will tell on that when pulling a trailer up a pass. Some have reported seeing an increase in MPGs, but who knows.. that's for you to decide.

Now for the real fun, I had been driving around in "Economy" the past couple of months and switched it back into the "Street Race" setting... oh yeah.. shift into second, give half throttle, intake growls with even more authority than it had before (grrrrRRRAHHH!!) turbo whistles (whhhyyyyyeeEEEEEEE!!! like a 737 taking off down a run way) exhaust blaring (brrrrRRRRRR)... truck sort of gallops ahead in a way that a horse does suddenly while on his back. Do the same thing again only this time 3/4 throttle and you spin off the rear tires suddenly once the engine catches boost.... tachometer light switches before you have time shift. Is it a 600HP tuned 6.7? Heck no! But is it still fun to drive? Abso-frequen-lutly. :)
 
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