MIBagentQ

iTrader: (3)

Does anyone have any experience with this cat? Curious to what the diameter of the piping is and the reliability of the core. I have the rx7store.net high-flow cat but after 4 years my car now stinks and does this now so I need to replace the cat.

David Hayes

iTrader: (6)

Interesting. You might want to call Magnaflow and ask them about the flow rate of the unit so you can compare it to your rx7store unit.

gracer7-rx7

iTrader: (16)

Keep blowing massive flames out the tail pipe and you'll BBQ the next cat also.

jacobcartmill

iTrader: (6)

i would personally recommend that if you use a big brand like Magnaflow, make sure it's a hi-flow cat, and not a typical honeycomb style.

i recently used a 3" universal magnaflow cat, and it cracked down the middle because (i think) of the rotary heat while cruising on the interstate.

99.9% of the cars on the road are piston engines, so i think these typical cats are made for piston engines' relatively cool exhaust (compared to our rotaries).

MIBagentQ

iTrader: (3)

I went ahead an ordered it anyways since my focus this year is to simply drive the car on the street whereas previous years I was doing time attack and really needed the power more. I really do need to reduce the smell and smoke more than anything else right now, my wife won't even take a ride with me the way it is :S

Compared to the rx-7 store cat, there appears to be more core volume at least looking from the outside, inner diameter is much smaller at 2.25" versus 2.8" for the rx7store cat, this represents about a 36% reduction in cross sectional area.

A few pictures:

j9fd3s

iTrader: (3)

in the 21st century the rotary EGT is about the same as a piston engine, especially with a factory ECU.

the difference is that the rotary has much stronger exhaust pulses, so its almost literally like hitting the cat with a hammer.

the smaller piping doesn't help, but i would imagine that the restriction is going to be the cat in either case...

jacobcartmill

iTrader: (6)

i'd be willing to bet the rotary EGTs are hotter both while cruising and while at full throttle.

Natey

iTrader: (19)

I have a newish cat (+- 50 miles or so) that I use to smog the car, then I take it straight back home and put in my old blown-out Bonez that flows better.
Save yourself a few bucks and keep the new one around for that ONE day.

j9fd3s

iTrader: (3)

the key word is stock ECU, with the stock tune you won't see any higher than about 720c, because the cat melts @650c...

the newer BMW turbo engines run @1150c at wot (and like 250f coolant, and 300f oil temps), somehow they don't melt cats...

Sgtblue

iTrader: (16)

Late arrival, but I don't know about that magnaflow. If it were a "direct-fit", why undersize the inlet and outlets?
I have Bonez that's likely over 15 yrs old (had the car 11 yrs and it was far from new then). Lost the back half of the matrix this past winter because I dropped the damn thing on the shop floor taking it off for a transmission R & R. Removed all the loose bits and stuck it back on. A little louder, but it still doesn't stink. Probably replace it over the winter....and it's be another Bonez.

Dvst8

iTrader: (6)

OP, any updates or opinions on this Magnaflow cat?

DaleClark

iTrader: (55)

I think Magneflow was trying to copy the stock main cat, that's why the pipe diameter is so rinky dinky.

Almost wonder if it would be worth getting that cat and a midpipe and replacing the piping.

On a bone stock car, I imagine performance would be similar. Which is the idea here. It's not a performance part, it's a stock replacement.

FYI, it's $222 from Amazon.

Dale

04G35S

iTrader: (10)

I think at that point it would be cheaper to just buy a new 3" cat and have it welded into the old midpipe. Cut out the burnt up one and weld in a new one. Way easier, cheaper, and you can retain the 3" pipe.

I would return the Magnaflow ASAP!

Sgtblue

iTrader: (16)

Except most aftermarket cats won't last very long. Those that do aren't all that cheap/inexpensive.