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cat converter delete?

Fred Gwynne said:
:lol:


Didn't the cat kind of kill off the muscle car thing back in 1972?
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Massive drops in compression ratios due to octane changes killed the so-called muscle cars.

Catalytic converters converters made their way onto the scene in the mid-late 70's and the technology was primitive. Massive bead-filled containers that sucked the life out of an engine... but that was before we went to extruded ceramic core cats.

Converters today are efficient and cause relatively little power loss. I'm not sure why you bumped a three year old thread for this. Did the owner of the "catless" 240 have his car dyno tuned before and after or perhaps does his butt dyno need to be recalibrated?

Me personally after having NOT run catalytic converters for years can tell you the stink of a catless car outweighs any trifling power loss. I've used the spun-metal core cats for a couple years now and haven't noticed anything in the area of loss.

ymmv.
 
PromiseRing said:
I bashed out the innard of my car and noticed no difference in sound/power. I think it may have stunk a little bit though. You may be able to sell it for $20 as well.
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Are you the previous owner of my car? Because that was done to mine. Was a nice surprise when I had my first emissions test.
 
740atl said:
I'm not sure why you bumped a three year old thread for this.
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As stated in my post dated 8/15/18 at 8:09 PM, I bumped this thread because I want to read some comments/thoughts about the possible performance benefits of cat removal and the value of the post made on thevolvoforums.com.

Thankfully there were some pretty good responses and I learned a few new things. Give yourself a pat on the back because you did a good job.



And FWIW I'm not gutting or removing the new cat on my car that was installed this past May.
 
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Not sure if it applies here particularly, but I would unbolt and bolt-on the cat on my old 944 (Porsche) and there were definitely sound AND performance differences. Although louder without the cat bolted on, there was definitely some performance LOSS. I chalk it up to lack of back pressure since it was NA and basically open exhaust at that point.

I would venture to say with an NA engine, removing the cat would cause a loss of power, albeit very miniscule; with a forced induction engine, it makes sense there would be a slight gain. Obviously it's gonna be louder without the cat.
 
I would like to add, my 83 B23E has no cat, the testing station man has commented a couple of times about it and I just tell him it predates them.

The exhaust looks factory, never touched from memory.
 
ogamer777 said:
Not sure if it applies here particularly, but I would unbolt and bolt-on the cat on my old 944 (Porsche) and there were definitely sound AND performance differences. Although louder without the cat bolted on, there was definitely some performance LOSS. I chalk it up to lack of back pressure since it was NA and basically open exhaust at that point.

I would venture to say with an NA engine, removing the cat would cause a loss of power, albeit very miniscule; with a forced induction engine, it makes sense there would be a slight gain. Obviously it's gonna be louder without the cat.
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psych element factor:
louder exhaust, with zero power change can make you feel "hmm, usually this much noise make me go faster, must be down in power. YMMV.
 
I just bought a stainless vibrant performance 7100 2.25 cat with metal core. I can't give it a review yet as I'm still waiting on my coated manifold before I install everything.
 
Might be a while. Looks like a need another manifold to send. Got damaged. Also I bought the Vibrant based on reviews, the core material, and the fact it was cheaper than a standard stainless cat(with the deal I got on ebay).
 
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