How to gut your primary cats (Dyno results to come soon)
06-26-14, 02:57 PM
#31
Instructor
something I would never EVER do. I maybe old I guess now, but the smell and odors for 10 HP to me isn't worth it.
I hate smelling like exhaust, even after putting several cats in my mk3 2jz no it still stinks, There is nothing like an OEM cat, too bad there isn't a company that makes a real quality high flow one.
I hate smelling like exhaust, even after putting several cats in my mk3 2jz no it still stinks, There is nothing like an OEM cat, too bad there isn't a company that makes a real quality high flow one.
06-26-14, 03:08 PM
#32
Lou
Last edited by flowrider; 06-26-14 at 03:59 PM.
06-26-14, 07:43 PM
#35
Yeah not sure I'd decat the entire exhaust... the F is a refined sports car, don't want it smelling like an old muscle car. Defeats the purpose of gutting the primary cats only to restrict flow by adding aftermarket cats. My current setup with the secondary cats and mufflers removed doesn't smell like anything.
Last edited by VtotheJ; 06-26-14 at 08:00 PM.
06-29-14, 08:11 AM
#37
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My brother has a Joe Z exhaust (which smelled totally stock) but once he threw on a set of Sikky Headers on his ISF which removed his primary cats, the gas smell was very prominent. If he idled too long at a light the fumes would enter the car through the AC vents. I just sold my supercharged vette that did the same thing. I could never let the car idle in the garage (even with the garage door open) or it would fume up my garage and it would be unbearable. A part of me likes the sound, but the other part of me fears cancer from the fumes haha.
On another note, this spark plug non fouler trick may work in place of the O2 sim! You can buy two pairs of them from auto zone for like $4 a pair, and drill 2 of them out with a 1/2" drill bit, then stuff some steel wool in between. It goes 02 sensor > drilled non fouler > steel wool > undrilled non fouler > and then the header or exhaust. Not sure how effective it is on the lexus, or if its a good idea to use in the headers, but definitely worked for my 350z I used to have when I removed the cats and went with a straight pipe. My CEL turned on for a couple days and never came back again after this trick. I can post the link to the DIY with pics from an old 350z forum if I'm allowed by the mods to share it here. Again, not sure how effective it will be with our cars but worth a shot.
On another note, this spark plug non fouler trick may work in place of the O2 sim! You can buy two pairs of them from auto zone for like $4 a pair, and drill 2 of them out with a 1/2" drill bit, then stuff some steel wool in between. It goes 02 sensor > drilled non fouler > steel wool > undrilled non fouler > and then the header or exhaust. Not sure how effective it is on the lexus, or if its a good idea to use in the headers, but definitely worked for my 350z I used to have when I removed the cats and went with a straight pipe. My CEL turned on for a couple days and never came back again after this trick. I can post the link to the DIY with pics from an old 350z forum if I'm allowed by the mods to share it here. Again, not sure how effective it will be with our cars but worth a shot.
Last edited by RedlineAZ; 06-29-14 at 08:19 AM.
06-29-14, 11:11 AM
#38
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My brother has a Joe Z exhaust (which smelled totally stock) but once he threw on a set of Sikky Headers on his ISF which removed his primary cats, the gas smell was very prominent. If he idled too long at a light the fumes would enter the car through the AC vents. I just sold my supercharged vette that did the same thing. I could never let the car idle in the garage (even with the garage door open) or it would fume up my garage and it would be unbearable. A part of me likes the sound, but the other part of me fears cancer from the fumes haha. On another note, this spark plug non fouler trick may work in place of the O2 sim! You can buy two pairs of them from auto zone for like $4 a pair, and drill 2 of them out with a 1/2" drill bit, then stuff some steel wool in between. It goes 02 sensor > drilled non fouler > steel wool > undrilled non fouler > and then the header or exhaust. Not sure how effective it is on the lexus, or if its a good idea to use in the headers, but definitely worked for my 350z I used to have when I removed the cats and went with a straight pipe. My CEL turned on for a couple days and never came back again after this trick. I can post the link to the DIY with pics from an old 350z forum if I'm allowed by the mods to share it here. Again, not sure how effective it will be with our cars but worth a shot.
06-29-14, 04:07 PM
#39
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http://my350z.com/forum/engine-drive...-fix-pics.html
In talking to a guy from that forum, he PM'd me this stating it wasn't a good idea to use any sort of spacer for the 02 sensor in the headers.
"you have two sets of o2 sensors. upstream ones (before the cats) in the headers. down stream ones (after the cats).
the upstream sensors are what the ecu uses to control the fuel trims.
the downstream ones are simply there as a check to ensure the cats are working... they run a check to see if the exhaust is cleaner than what the upstream sensors are seeing.
the nonfoulers space the sensors out of the path of the direct path of the exhaust. You don't want to play games with the upstream sensors because they, like I said, play a role in how much fuel the car is being fed"
In talking to a guy from that forum, he PM'd me this stating it wasn't a good idea to use any sort of spacer for the 02 sensor in the headers.
"you have two sets of o2 sensors. upstream ones (before the cats) in the headers. down stream ones (after the cats).
the upstream sensors are what the ecu uses to control the fuel trims.
the downstream ones are simply there as a check to ensure the cats are working... they run a check to see if the exhaust is cleaner than what the upstream sensors are seeing.
the nonfoulers space the sensors out of the path of the direct path of the exhaust. You don't want to play games with the upstream sensors because they, like I said, play a role in how much fuel the car is being fed"
06-29-14, 04:30 PM
#40
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Yea, you would use them in the rear 2. I've had some success with that method on other cars.
The best method is turning the code off completely in the ecu but not really an option on this platform lol. Wonder if sard can atleast accomplish that if one is spending a fortune for their flash.
The best method is turning the code off completely in the ecu but not really an option on this platform lol. Wonder if sard can atleast accomplish that if one is spending a fortune for their flash.
06-29-14, 08:01 PM
#41
Yea, you would use them in the rear 2. I've had some success with that method on other cars.
The best method is turning the code off completely in the ecu but not really an option on this platform lol. Wonder if sard can atleast accomplish that if one is spending a fortune for their flash.
The best method is turning the code off completely in the ecu but not really an option on this platform lol. Wonder if sard can atleast accomplish that if one is spending a fortune for their flash.
07-01-14, 08:48 PM
#44
Lexus Champion
From a recent thraed I posted in
"I'll be your dyno....
Me and Slay raced not to long ago. We both data logged our cars, wot runs and A/F mixtures were great.
We raced from a 40mph roll till 160mph. We were head to head. At 90, 120, 140mph I jumped a foot at each. At 160mph I was only up by 3 tiny feet.
My car: afe filter, ppe header, iss des cat back, iss scoops (a whole lotta $)
Slays: gutted primary cats w/ ppe 02 conditioner, replaced mufflers & secondary cats with straight pipes (he saved a lot of $, lol) "
"I'll be your dyno....
Me and Slay raced not to long ago. We both data logged our cars, wot runs and A/F mixtures were great.
We raced from a 40mph roll till 160mph. We were head to head. At 90, 120, 140mph I jumped a foot at each. At 160mph I was only up by 3 tiny feet.
My car: afe filter, ppe header, iss des cat back, iss scoops (a whole lotta $)
Slays: gutted primary cats w/ ppe 02 conditioner, replaced mufflers & secondary cats with straight pipes (he saved a lot of $, lol) "
07-02-14, 08:03 AM
#45
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Dyno is booked July 12th at noon
Yes there is a CEL associated
Yes the Sikky conditioner removes the CEL
Yes there is a smell associated... not sulphur, more gasoline/ rich combustion
Yes the dust from the CAT is bad ****, wear a longsleeve, mask and eye protection.
Yes the car is much quicker
All directly from the car owner...
Yes there is a CEL associated
Yes the Sikky conditioner removes the CEL
Yes there is a smell associated... not sulphur, more gasoline/ rich combustion
Yes the dust from the CAT is bad ****, wear a longsleeve, mask and eye protection.
Yes the car is much quicker
All directly from the car owner...
