I figured I'd make an in depth thread about this while it's all still fresh in my mind. I just put a set of Kooks 1 3/4 3" longtubes on my car over the winter months. And just a few days ago I put a set of ARH 1 3/4 3" longtubes on a customers car at work.
Kooks:
-moderately tough to get to all head flange bolts. Some harder than others, but none super hard.
-2 piece slip fit primarys, goes around steering shaft which can make it somewhat challenging and opens another possible spot for leaks.
-dipstick does not need to be removed for kooks install
-clearances are VERY tight. One primary rubbed my stock K member. While I've heard others say they clear fine. Seems to be hit or miss on this.
-The primary routing makes it basically impossible to get motor mounts on/off with headers installed
-Midpipe fits easy, however it pushes the catback to the rear 1-2". Heard this is fine on an irs car but my car(sra) it made everything very tight and a pain to fit.
-Midpipe to header connection is ball and socket. Better design for easy of install/removal in my opinion.
ARH's:
-Very hard getting flange head bolts. Not impossible by any means but significantly more challenging than the kooks.
-1 piece primary's, steering shaft goes on outside of primarys and has roughly 1" of room, clearance for days.
-overall clearances are very good. Much better than the Kooks. atleast 1/2" everywhere.
-dipstick DOES need to be removed to install, then ran thru the primary tubes to get back in
-motor mounts still easily removed/installed if needed to change them later. Also helps getting to the flange bolts with them out.
-Midpipe also fits very easily. But just like the kooks, it pushed the catback back atleast an inch. Not sure why it's so hard for a header company to make midpipes at stock locations.
-header to midpipe is a slip fit. Easy to install but can be very hard to remove if clamps are every over torqued or left on for years at a time.
Overall opinions: Both are super high quality and great pieces. My personal preference I'd always suggest the ARH's. I'm not a fan of the slip fit primarys and the clearances are tight. Negatives being that install itself is harder(getting to bolts and dipstick remove/install). If you have really large hands and dont have access to stubby/cut wrenches and have an aftermarket K member go with the kooks. For everyone else I'd suggest the arh's.
Pictures of my Kooks setup:
Pictures of ARH's.
Kooks:
-moderately tough to get to all head flange bolts. Some harder than others, but none super hard.
-2 piece slip fit primarys, goes around steering shaft which can make it somewhat challenging and opens another possible spot for leaks.
-dipstick does not need to be removed for kooks install
-clearances are VERY tight. One primary rubbed my stock K member. While I've heard others say they clear fine. Seems to be hit or miss on this.
-The primary routing makes it basically impossible to get motor mounts on/off with headers installed
-Midpipe fits easy, however it pushes the catback to the rear 1-2". Heard this is fine on an irs car but my car(sra) it made everything very tight and a pain to fit.
-Midpipe to header connection is ball and socket. Better design for easy of install/removal in my opinion.
ARH's:
-Very hard getting flange head bolts. Not impossible by any means but significantly more challenging than the kooks.
-1 piece primary's, steering shaft goes on outside of primarys and has roughly 1" of room, clearance for days.
-overall clearances are very good. Much better than the Kooks. atleast 1/2" everywhere.
-dipstick DOES need to be removed to install, then ran thru the primary tubes to get back in
-motor mounts still easily removed/installed if needed to change them later. Also helps getting to the flange bolts with them out.
-Midpipe also fits very easily. But just like the kooks, it pushed the catback back atleast an inch. Not sure why it's so hard for a header company to make midpipes at stock locations.
-header to midpipe is a slip fit. Easy to install but can be very hard to remove if clamps are every over torqued or left on for years at a time.
Overall opinions: Both are super high quality and great pieces. My personal preference I'd always suggest the ARH's. I'm not a fan of the slip fit primarys and the clearances are tight. Negatives being that install itself is harder(getting to bolts and dipstick remove/install). If you have really large hands and dont have access to stubby/cut wrenches and have an aftermarket K member go with the kooks. For everyone else I'd suggest the arh's.
Pictures of my Kooks setup:
Pictures of ARH's.