Punched out the Cat and increase power

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Fiatracertracer
Posts: 160
Joined: Sat Aug 23, 2014 11:12 pm
Your car is a: 1982 Fiat Spider - Lip Stick Red
Location: Wilton, Connecticut

Punched out the Cat and increase power

Post by Fiatracertracer »

I was experiencing poor performance, EGR light was on steady so i decided to remove and look through the cat to see what it looked like inside, and I couldn't see through the mesh, no light through it. I knew then that a new cat would be in my future.

But before going out and buying a new replacement catalytic converter, I wanted to see if I could clear out the innards of the old CAT, reinstall it and see if there was any noticeable performance gain..... and was there ever.

I punched out all the catalyst using a 24" long 3/4" pipe from home depot and a small sledge hammer. Then pulled out all of the surrounding mesh with a long needle nose pliers and a heavy duty vise grip as a lever to pull it out.

The performance gain is incredible. My take offs and throttle response is now better then it ever was. Not sure what the HP gain is but it feels like I may have gained about 100 more HP give or take LOL :). Kidding of course but whatever the HP gain is ..... punching out the cat is worth it.

The EGR light went out and the car sounds throatier.

Here is what I have done so far:

Changed the oil... Mobil 1 - 5w40 turbo diesel truck.
Changed the rear end gear oil .... 80-90.
Changed the manual transmission oil .... GL-1.
Changed all the shocks with KYB, ball joints and tie rods.
Removed the CAT, gutted it and reinstalled it.

Fist time that my speed needle went past the end of the dial, while the car tightly hugged the road and remained steady and true.
Last edited by Fiatracertracer on Mon Sep 14, 2015 6:22 am, edited 1 time in total.
1982 Fiat Spider in restoration
zachmac
Posts: 1278
Joined: Sun Aug 24, 2008 9:20 am
Your car is a: 1978 Spider [1979 2 ltr engine]
Location: Aiken, SC

Re: Punched out the Cat and increase power

Post by zachmac »

Dude, feeling empowered by knocking out a feline is hardly cricket! :D Better make sure PETA doesn't hear about this.

Seriously though, its basically a poor man's "test pipe". I assume you are somewhere emissions exempt?
Jeff Klein, Aiken, SC
1980 FI Spider, Veridian with Tan (sold about a year ago), in the market for another project
1989 Spider, sold
2008 Mercedes SL65
2008 S600 Mercedes V12
Fiatracertracer
Posts: 160
Joined: Sat Aug 23, 2014 11:12 pm
Your car is a: 1982 Fiat Spider - Lip Stick Red
Location: Wilton, Connecticut

Re: Punched out the Cat and increase power

Post by Fiatracertracer »

zachmac wrote:Dude. I assume you are somewhere emissions exempt?
Yes.

Doing wholeshots at take offs now.

New cat on order, I plan to test the difference.
1982 Fiat Spider in restoration
TStark
Posts: 127
Joined: Thu Sep 26, 2013 10:24 am
Your car is a: 1975 Spider
Location: NE CT

Re: Punched out the Cat and increase power

Post by TStark »

Punching cats and kicking pigeons in the park...

Careful with the launches tiger, less you want to source a new rear axle!
TX82FIAT
Posts: 1814
Joined: Mon May 03, 2010 11:04 am
Your car is a: 82 Fiat Spider 2000 CSO
Location: San Antonio

Re: Punched out the Cat and increase power

Post by TX82FIAT »

Did the CAT modification years ago before going to a straight pipe, resonator, muffler set up. It does make a difference. However, I did notice on my car there was a tin (tinny) sound that came out at certain RPM levels.

Yes, I live in an emissions exempt city.
Buon giro a tutti! - enjoy the ride!

82 Fiat Spider 2000
03 BMW M3
07 Chevy Suburban
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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: Punched out the Cat and increase power

Post by bradartigue »

We used to punch out the shells to pass visual; the numbers were still well below threshold. Another example of the Spider being a clean running engine.
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