Cat Delete Project

[DoctorV8]

Fubar,

What kind of gains are you expecting from your cat delete project?

I, for one, have grown tired of the smell of my catless Lingenfelter stroker ZR-1, and plan to install a set of high flow units on it. The incremental performance gain isn't worth it to me.

 

[Fubar]

What kind of gains are you expecting from your cat delete project?

Honestly, I am not expecting any hp gain or very little. Changing the exhaust systems has never produced much hp gain for me. I just wanted an excuse to get in to my GT's engine bay and look around. The primary objective is to test different exhaust sounds (volume/tone). I may have a short header made. One that would fit in to an otherwise stock system. I hadn't given any thought to the "smell." Too much gas in there?

 

[BlackICE]

Fubar,

What kind of gains are you expecting from your cat delete project?

I, for one, have grown tired of the smell of my catless Lingenfelter stroker ZR-1, and plan to install a set of high flow units on it. The incremental performance gain isn't worth it to me.

I am running the FRPP pipes and the smell was bad at 1st. Now after the car is warmed up the smell is almost gone. I can pull the car into the garage after a drive and let it run for minutes without the garage smelling like an EPA cleanup site! The fix is to finely tune the MAF table in the lower range especially during idle, with and without the a/c turned on. I had to make corrections greater than 10% in some of the cells! Letting close loop operation zero in the correct fuel mixture every time is not as good as it can be with the MAF values closer to reality. Someday I hope to get the car on the sniffer to see what it is acually putting out. My nose to the tailpipe tells me it will be very clean for a catless car.

 

[Fubar]

Okay, I have run into my first snag. One of my wheels fell over and the front side was damaged. This wheels are painted right? (not powder coated). Anyone know the paint code? These are standard wheels.

 

[kumar]

am i the only one that likes that smell?

 

[BlackICE]

am i the only one that likes that smell?

It is a smell that can kill you!

 

[Ed Sims]

smells like?

Hey, if looks can kill why can't smell kill?

Ed

 

[ViperJoe]

Okay, I have run into my first snag. One of my wheels fell over and the front side was damaged. This wheels are painted right? (not powder coated). Anyone know the paint code? These are standard wheels.

The wheels are powder coated which largely negates a touch up. I tried touch up using ~ 4 different shades and couldn't get close to a match. Finally sent the wheel out for refinishing. Looks great now!

 

[S592R]

OUCH! oh well here's your chance to have the wheels polished. :wink

 

[Fubar]

The first stage of the project is complete. I have reinstall the factory manifold (now ceramic coated). The cats are gone via Ford Racings Cat Delete kit. It is louder but still not ridiculous.

Pix:

My assistant

Stock manifold before coating

Manifold after coating

Manifold with copper nuts (I like the contrast)

Manifold with heat shields in place (they were ceramic coated also but with a metallic finish)

I will let you guys know what it Dyno at when I get the numbers. I think I need to run it a bit just to let the computer readjust (battery was disconnected for two weeks).

Then I will go through this process again with the headers.

 

[Fubar]

Scary things:

I just ran the beast on a Dyno Dynamics machine. HP was as I expected 550whp (add 18% for Dyno Jet conversion) but the A/F was scary lean. 16.5 to 1. It may have been operator error, they were pulling the A/F out of the tail pipe not an O2 bung. Has anyone had problems with a cat delete doing something like this to the engine? One of the tech suggested that the post cat O2 sensors might see that the exhaust has a lot of fuel in it and tries to lean it out. However, I thought that WOT was a preprogrammed set of A/Fs?

 

[californiacuda]

If there is a slight leak in the exhaust track, when the cylinder firing pulses, air can be drawn back into the exhaust. The O2 sensor sees some air from the leak and reads lean.

You can check with a cheap pair of automobile stethoscope for any exhaust leak. I recently reworked my exhaust and had this happen to me. Oh, the exhaust from the car smelled rich, because to O2 sensor read lean from the outside air, and was adding fuel to compensate.

 

[Fubar]

Thanks, that makes perfect sense. (I love this forum)