Any performance gains (obvious. spool faster) with gutting our stock downpipe of the -->
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Any performance gains (obvious. spool faster) with gutting our stock downpipe of the -->
pre cat and is there room to put a couple non foulers on the 02 bung so you can trick the 02 sensor, anyone done it or think it might have some benefits?
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I think you mean "gut the stock catalyst".. yes?
there's nothing inside the stock downpipe to remove..
I did gut a hi milage factory cat (it had been replaced due to codes)
the good:
the engine made more midrange power... a noticable amount
it ran VERY quiet... there's no increase in noise level at all
the not so good:
compared to the MUCH more substantial power increase produced by a 3 inch down pipe.... the power increase hardly justified the effort
AND, the effort was substantial... it's a b*tch to remove the internals from the cat. It's a VERY robust honeycomb structure. There's no easy way to do it. It took several hours with a low speed, high powered drill and a long 3/4 inch bit to repeatedly drill through and break the honeycomb out of the catalysts... remember, there's 2 small parallel cats in the stock system, so you do it twice
second: 2 non foulers stacked, fit Ok, but they're not enough to stop the CEL's in this configuration. I continued to get "converter low efficiency" codes. Wayne Schmidt's block might do it, though
bottom line: gutting your cat is more trouble than it's worth...
I did gut a hi milage factory cat (it had been replaced due to codes)
the good:
the engine made more midrange power... a noticable amount
it ran VERY quiet... there's no increase in noise level at all
the not so good:
compared to the MUCH more substantial power increase produced by a 3 inch down pipe.... the power increase hardly justified the effort
AND, the effort was substantial... it's a b*tch to remove the internals from the cat. It's a VERY robust honeycomb structure. There's no easy way to do it. It took several hours with a low speed, high powered drill and a long 3/4 inch bit to repeatedly drill through and break the honeycomb out of the catalysts... remember, there's 2 small parallel cats in the stock system, so you do it twice
second: 2 non foulers stacked, fit Ok, but they're not enough to stop the CEL's in this configuration. I continued to get "converter low efficiency" codes. Wayne Schmidt's block might do it, though
bottom line: gutting your cat is more trouble than it's worth...
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