Starting car without Y pipe & info on cats

[bigdoggee]

Just wondering if anyone has ever tried it? Or does anyone know if there are any problems if I were to do it? I'm trying to figure out if I need cats. I have taken the y pipe off... I just don't know how to tell if the cats are any good. Would like to save the expense of replacing if possible...

 

[sdpatt]

It will be VERY loud and very bad for your health with the exhaust in the engine and passenger areas. The lack of an exhaust system will rob the engine of the scavenging effect of the flow in the exhaust tubing. Not a good idea.

To check the cats you must check the cats. Use a leaf blower or other low pressure, high volume air supply (an air compressor is high presure, low volume) to find out if the flow through the cats is without obstruction. Good cats won't change the pitch of the leaf blower motor much at all. Indicating that there is little resistence to the flow. If the cat is plugged, the motor (engine) will speed up because there is less flow through the pipe and less work for the motor to do.


------------------
Scott

1991, 252K miles, glass hood, police grill, SVO shifter, Catz fogs,
K&N, 73mm MAF, Superchip, PP Y-pipe, Borla cat-back, 190 lph pump
Eibach/Tokico/polyurethane, SHO Shop front & rear strut braces,
16x7.5" Moda R1, 225/55ZR16 Bridgestone RE730, -1 deg camber x 4,
Class II hitch, Silver award at the SHOklahoma Car Show

 

[RStalveyARFF]

I started it up once before I had the y-pipe back in after doing my clutch, just to hear it. I think it may be louder than a open headered V8. You'll throw CEL codes like crazy also since the O2,s won't be talking to the computer. Finally, the exhaust will be the richest you've seen, since the 02's won't be there the help meter the fuel flow.