just wanted to give my opinions on RRM magnaflow hi flow cat for all the curious folk out there.

Installation

Straight forward. Some prep notes: be sure to pick up 2 gaskets before install. Also, thoroughly WD40 your nuts and bolts before hand. Mine were rusted something evil, and my arms sore because of it

Also, RRM includes 2 bolts, 2 nuts and 4 washers. However, for install you need double that, and lock washers so they don't vibrate off. It would be nice if RRM threw in 2 more bolts and nuts, but since they didn't, you'll have to fetch them yourself.

Since I have headers, I flipped around my cat so the sensor tap is toward the rear, so the second o2 sensor is after a catalytic converter, eliminating the need for MIL eliminator, and no more CEL . I say, if you plan on getting headers, you should do this while your installing it, 2 birds, 1 stone.

The biggest problem revolved around the flanges. I know they had to be custom made, but they didn't exactly match up to the stock ones, they were slightly off. Also, the holes on the flanges are HUGE. I know RRM does this so it will fit aftermarket downpipes and catbacks, but it just caused problems. I had to double up on washers just so I wouldn't lose the washer in the hole.

Performance
After install, I took it for a spin on the highway/on/off ramps to test it out at high speed. As I hoped, no pending CEL for the o2 sensor. I don't think its much louder than stock, in fact, it sounded a touch quieter than stock cat, but it was really close

As far as leaks, I think i'm good to go, didn't feel any escaping gas around the flanges, and I didn't hear anything, so I think I'm good.

Top end feels pretty good. The only thing I can compare it to is slapping on headers for the first time. 60 to 80 mph felt a lot better, like going from stock to aftermarket headers. Didn't feel too much difference down low, but up top it was a bit better. I'm not talking 20hp here, probably just a handful if that, but still a worthy addition. And I'm still n/a, so FI guys should feel a good difference.

Overall, pretty good mod, almost a must for guys planning to go or already have gone FI. Definately a better option than the loud test pipe, so its all good. I think RRM needs to make a few tweaks to the flange size and position, and then it will be perfect.

 

sounds good, nice write up. seems that for all that the HFC is worth they should have things right the first time. especially with the bolts, i mean c'mon. i have to go find bolts and washers too?

 

yeah, well, ya know, maybe this thread will bring some stuff to robs attention to make it even better.

i think if you are FI, this or another HFC should already be on your car, so hopefully a HFC is on your shopping list arch

 

i hope rrm corrects their oversights on this product. sounds nice, when i get exhaust ill have to order one

 

nah, i got the test pipe.

 

 

YOU HEARD ME!

 

oh yeah, forgot to mention:

did a bit more driving and the car feels alot better. before i was having some troubles, it felt like someone stole 50% of my hp, but now the lancer feels back to normal, like it should

i honestly think the messed up readings coming from my o2 sensors before threw it into some closed loop of death (had the MIL eliminator wired up, but it never worked, and got a "slow response from sensor" error code.

but with everything wired up right and reading like it should, it just feels better going around town. hard to explain, but it feels good.

i was even pushing it hard on the highway again, but had to slow down when my alarm went off "danger to manifold"

 

nice write-up, please dont refer to F&F, lol. i guess i'll be buying one of these after i get everything for the turbo including ur header on my car. i have the cash btw, i just gotta go deposit it tomorrow and send u the money!! please pm me w/ ur info. paypal, etc. rite now i gotta a STINKY test pipe, but it'll have to go.

 

yeah, i'm not a personal fan of the test pipe, even if it does yield 15hp over a hfc (not sure if it does, just example): its obnoxiously loud and spews out stinky polluted gas (more than a cat converter would)

YGPM

 

The highflow cats are made on the same jig that the testpipes are made on with the same flanges used as on the testpipes. For over 2 years and a couple hundred test pipes there have been no issues with fitment. The flanges used are so that people going with different manufactures exhaust systems have some slack on installs. It would really **** people off if they couldn't bolt their catback up to the cat due to slightly different flanges between different manufacturers.

As for the bolts RRM provides all 4... they must have been a shipping error. I'm forwarding this post to ROCK so he can follow it.

Agian another good critical post from one of RRM's favorite customers. Great review and glad it all worked out overall.

 

ROFL......even i gotta admit that was good


yeah, i know about the flanges: you want it to fit like a glove, but then again you want some "slack" in the system to fit different headers and exhausts, so yeah, i know you can't have it both ways, its just one of those things. As long as there aren't leaks, then its all gravy (another reason to get fresh gaskets).

also, i didn't mention this before, but some minor fitment issues may have been caused by the fact that i strapped it on backwards. Not sure, but thought I'd mention it

good to hear about the bolts. I thought RRM was just teasing us by providing 2. thanks

 

Did you have to extend your first o2 sensor wire? If so how long and where?

 

Thanks for write up. We know it takes 4 bolts and nuts. One of my guys goofed. We owes you a couple bolts and nuts. Everything else is by design.

ROAD/RACE

 

yeah, had to extend it i'd say about a foot or less. where? if you look under your car, right about the cat location, there is a rubber thingy (grommet maybe) 4 wires are poking out of (white, blue, 2 black). i just snipped them off 3 inches from the rubber thing and extended the sensor tail with the sensor off the cat (was a lot easier to do when your not under your car)

but you do need to solder the extended tail back onto the short wires underneath your car, which can be a little hard unless your pretty good. i just used a micro butane torch because i couldn't be too precise with my soldering tip.