Luxy60

I'm considering a flame arrestor to replace the stock unit on my 454Mag EFI. Looking seriously at the Gaffrig or EMI versions (screen vs. cloth/ paper element). Looking for any feedback on either of these models. Also considered the Vortec but I'm not sold on the KN type filter, seems like it would be a pain in the butt to clean/ oil. How long can you typically go between cleanings on these filters?

jdnca1

I have K&N's on my TR setup with xtreme tops. Clean/re-oil once a year, and thats probably too much!

deboatmon

I would like to hear any pro's / cons on the use of aftermarket EFI Flame arrestors. Most manufacturers state substantial increase in airflow with their respective pieces. Do any third party, documented tests exist that can substantiate any manufacturers claims ? I can't see gaining any realistic horsepower switching from Merc to aftermarket EFI flame arrestors. At the price the aftermarket pieces sell for, they should work great. I've also read of some difficulties in installation of some manufacturers types on some applications.

K&N makes great stuff. I use their filters on my dually and two autos. I use them for the improved filtering and longer life, not looks. And they are not too expensive. It would be hard to go wrong with K&N on pretty much anything.

My guess is that many people will buy aftermarket flame arrestors just for the custom, non stock look. Kind of like adding chrome valve covers and breather to a tired old 265 Chevy. Not that I wouldn't do it myself. I kind of like the look of the aftermarket stuff too. But, does it make any power ?

Luxy60

I believe that the aftermarket flame arrestors do provide more and improved airflow vs. the stock unit from Merc. How much depends on who you talk to. I've heard anywhere from 35 - 100%! Same for HP gains. I seen advertisements in the 5 -15 hp range. Which in itself is not going to result in much of a MPH increase (maybe 1 -2 mph, if your engine can take advantage of the extra air). I like the look of an aftermarket units (EMI, Vortech etc.) and from reading others feedback it does seem like they help reduce transom soot with the EFI motors. Reason enough for me to add one. The KN type filter will provide better filtration than the mesh just seems like it would be a pain to maintain??