Hi-Flow aftermarket cat?

[romcat]

Hi:

Time for a little more power from my 93 Loyale wagon. Is anyone using an aftermarket hi-flow catalytic convertor. Not a gutted one but a working hi-flow model. If so what was the effect on power delivery and fuel economy.

 

I figure to initially replace the Cat, larger bore muffler/exhaust, K&N in the air box that should move more air through.

 

Maybe go up a wheel size also.

 

Cheers,

Gareth

[erik litchy]

id get a 2.25" 2 way cat to replace the stock 2. 2.25" exhaust from the cat to the tailpipe with the muffler of your choice (but most muffles dont fit unless they are very short in the oem spot). that would be a lot more efficient that the stock exhast that necks down to 1.5" in some areas.

[idosubaru]

i have a high flow converter but my mods and order of doing them are too convoluted to determine any changes. if you open up the exhaust too much you may see some low end loss which is annoying if you're driving up hills and such. highway gas mileage definitely goes up on the XT6 if you open the exhaust up a little (straight through muffler like dynomax is my preference), but too much and it goes nowhere and you loose low end power which is annoying if you live in hilly areas (at least to me it is).

 

i think kevin has some dyno plots of some before/after exhaust mods on his XT6 on http://www.xt6.net if you want to check there. he also has a high flow converter on one of his i believe.

[Myxalplyx]

Hi:

Time for a little more power from my 93 Loyale wagon. Is anyone using an aftermarket hi-flow catalytic convertor. Not a gutted one but a working hi-flow model. If so what was the effect on power delivery and fuel economy.

Cheers,

Gareth

 

Gareth,

 

Here's something I purchased from Autozone for my RX Turbo.

http://www.ultimatesubaru.org/forum/showthread.php?t=29648&highlight=cat+converter

 

For your wagon, I'd go to a 2" for better low end or a 2.25" for better overall performance. Try searching an autozone for a part # close to this one but in a smaller size. The one pictured is 2.5".

 

Here's what it looked like after being installed and sprayed with high temp paint.

http://www.ultimatesubaru.org/forum/showthread.php?t=29957&page=1&highlight=cat+converter

 

Gary,

That 3" cat converter is what I had already from a turbokit that I purchased off of 'Eric Witte' for that failed turbo XT6 job. Luckily, it did not seem to hurt the low end at all on the XT6. Kinda fascinating, wouldn't you say ole chap? (where that come from? )

[romcat]

Hey Kevin:

 

I followed your link. Looked good. Are these a higher flow unit than the stock piece?

 

Cheers,

Gareth

 

 

 

Gareth,

 

Here's something I purchased from Autozone for my RX Turbo.

http://www.ultimatesubaru.org/forum/showthread.php?t=29648&highlight=cat+converter

 

For your wagon, I'd go to a 2" for better low end or a 2.25" for better overall performance. Try searching an autozone for a part # close to this one but in a smaller size. The one pictured is 2.5".

 

Here's what it looked like after being installed and sprayed with high temp paint.

http://www.ultimatesubaru.org/forum/showthread.php?t=29957&page=1&highlight=cat+converter

 

Gary,

That 3" cat converter is what I had already from a turbokit that I purchased off of 'Eric Witte' for that failed turbo XT6 job. Luckily, it did not seem to hurt the low end at all on the XT6. Kinda fascinating, wouldn't you say ole chap? (where that come from? )

[Myxalplyx]

Hey Kevin:

 

I followed your link. Looked good. Are these a higher flow unit than the stock piece?

 

Cheers,

Gareth

 

I have no proof. My memory is foggy and I can not remember if the box it came in stated it was a higher flowing unit. I did dyno the car afterwards and it didn't seem to hurt the power delivery. I do remember asking for a high flowing cat instead of the OEM one and that is what I ended up with.

[romcat]

Hi Kevin:

 

What other mods had you done to the car before that? With a free-er breathing cat and reduced back pressure there should have been more power BUT only if the exhaust-muffler and the intake-improved air filter allowed more air passage themselves.

 

Cheers,

Gareth

 

 

 

I have no proof. My memory is foggy and I can not remember if the box it came in stated it was a higher flowing unit. I did dyno the car afterwards and it didn't seem to hurt the power delivery. I do remember asking for a high flowing cat instead of the OEM one and that is what I ended up with.