removing cats, do or don't?
#27
Is that thing Turbo?
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loose the cats if you can, made a huge improvement on my car and i had bonew highflow, i never felt the car with the tock cats i can't imagine the diff it'll make
#28
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Re: removing cats, do or don't?
Originally posted by boogerboy
I was thinking about removing the cats on my automaical 88 gxl, Should i only remove the precats? or both? or should i leave well enough alone, I have access to a pipe bender, welder, and probally anything else except a cnc shop (that would kick if i did though). im starting with the free mods to the car first, then as money builds up, a tranny swap is commin.
thanks for all the help!
clay
I was thinking about removing the cats on my automaical 88 gxl, Should i only remove the precats? or both? or should i leave well enough alone, I have access to a pipe bender, welder, and probally anything else except a cnc shop (that would kick if i did though). im starting with the free mods to the car first, then as money builds up, a tranny swap is commin.
thanks for all the help!
clay
#29
Rotary Freak
i have a 91 n/a automatic i am going to be taking off the cats but i dont know what to put in its place i dont want to mess with the 5th 6th ports will 1 bonez high flow cat work and replace the second cat with a straight pipe
#30
Rotary Freak
i have a 91 n/a automatic i am going to be taking off the cats but i dont know what to put in its place i dont want to mess with the 5th 6th ports will 1 bonez high flow cat work and replace the second cat with a straight pipe please answer some one that knows the for sure answer
#33
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Originally posted by DEZERTE
how do you "gut" a cat? (please dont make feline jokes )
how do you "gut" a cat? (please dont make feline jokes )
#35
whats going on?
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Originally posted by uRizen
Lol, that would be pretty bad ***, but I wouldn't want to get char marks on my bumper or end up setting some punk *** kid that happened to be walking by on fire.
Lol, that would be pretty bad ***, but I wouldn't want to get char marks on my bumper or end up setting some punk *** kid that happened to be walking by on fire.
#36
Originally posted by 91mazdarx7
did you replace both cats with a straight pipe or just 1 also did you have any engine mods or problems with your 5th 6th ports opening
did you replace both cats with a straight pipe or just 1 also did you have any engine mods or problems with your 5th 6th ports opening
#37
Rotary Freak
i got a stock s5 n/a can i replace the first cat with a high flow one and replace the second one with a straight pipe i wont suffer any problems with my 5th 6th ports or anything
#38
represent
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hmm, basically. but i have had rb headers, presilencer and catback, and im very very pleased with it. my car runs a small bit on the rich side of things, so the exhaust smells extra sweet and if i punch it a little bit and it happens to be night time, i can see the flash in the rear view of the '***** of fire' that come out of the pipes...someone described them as sort of molten looking ***** of gaseous fire...love it. oh, and its incredibly loud...if the windows are down it rings in my ears and people flick me off when i go past...its pretty amusing. but the whole racing beat exhaust will open up the airflow very nicely in the fc, and i havent had any problem with the 5th/6th ports not opening.
#39
Rotary Freak
yea i know the whole exhaust would be great but it would only be for alittle bit because im doing a tII swap so since its stock it would be better to have a high flow cat and a straight pipe for the second cat THIS WOULDNT GIVE ME ANY PROBLEMS WITH THE PORTS OPENING RIGHT? ........... also i know the heat would destroy a high flow cat but i forget where to get a high flow cat made for rotary engines can i get a link to buy one
#40
Resident autoglass pro
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I removed my primary cat. and replaced it with a stock pipe from a S5, gutted the secondary cat. and gutted the main cat. The exhaust is stock except for the gutted cats. With gutted cats. and no mufflers, just the Y-pipe, the car was LOUD. The secondaries open fine, but I routed the air pipe back to the main cat. since I retained it after gutting it. To gut my cats I just used a decent sized sledge, and a crow bar, a tire iron, and whatever else was long enough to jam down in there to remove the ceramic, or whatever is in them. I replaced all the gaskets, and used silicone sealer too. If you stock exhaust is in decent shape, this is probably the cheapest thing to do...
#42
XBL** Ownicus
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Ok, so by gutting the cats, you aren't loosing back pressure? If this is the case, I was kidna thinking maybe removing the first pre-cat, gutting the second, and adding a silencer in place of the main cat might be the way to go. I don't want to drive the neighbors nuts, but after some consideration, flame shooting wackiness sounds great to me.
#43
I used to have straight pipe all the way back on my 87 N/A. I just wanted to try it, and let me tell you...it is LOUD and it sounds like ***. Its not even a nice loud sound...its more like a huge gargling fart at lower RPM's, and it sounds like a pencil sharpener on crack at redline. 2 days later I put the exhaust back on.
-Joe
-Joe
#44
XBL** Ownicus
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lol @ pencil sharpener on crack. Does gutting the cats basically have the same effect as just putting a straight section there, or do they cause turbulance and deaden sound still?
Last edited by uRizen; 05-18-04 at 10:26 AM.
#45
Jesus is the Messiah
No, it doesnt. Its not a even good shape for flow. Just make a streight pipe and bolt it on, seriously. Dont destroy a perfectly good cat!
PS: Hey, just mail me your good cat and I'll mail you a streightpipe the same lenth, hows that?
PS: Hey, just mail me your good cat and I'll mail you a streightpipe the same lenth, hows that?
#46
Rotary Freak
so just 1 high flow cat will be enough for back pressure and not worry about the ports not opening and replace the other 2 cats with straight pipes? please answer quick thanks
Nate
Nate
#48
Rotary Freak
ok thanks everyone but where do i find the high flow cat made specifically for the rotary engines and which cat should i replace for the high flow cat on the closest to the manifold the middle one or the rear one
#49
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On the punching out a cat. No pun intended, I'm just wasted right now. I used a drill and one of those paddle bits. The ones that are flat for making big holes in wood.
#50
Rotary Freak
ok thanks everyone but where do i find the high flow cat made specifically for the rotary engines and which cat should i replace for the high flow cat on the closest to the manifold the middle one or the rear one
anyone?
anyone?