Guess the cats dont like a 175 shot huh?

 

I guess not. I need to get a breaker bar on these damn bolts. Spray and heat did nothing. I dont know why the hell these damn things are so tight.

 

I used a long impact extension and impact socket on my stock manifold bolts to get them off. The first time was a PITA for sure, PB Blaster works really well too.

 

cant you just weld in 2 pieces of straight pipe??

 

sure, that would be easy. But I want it to look 100% stock. So if they peek under during an inspection it looks stock.

 

ok i have a question. if i was to gut my cats on my sierra would it run a lot richer. Doesn't the lack of catalytic ceramics inside the cat cause the O2 to read funny and then dump more fuel into your motor? I heard this some where is this wrong or wat. need help.

 

Thats some BS old people at muffler shops say. They have no idea how technology works. The FRONT O2's measure fuel, the rear O2's read the exhaust gas coming out of the cat. A cat burns unburned fuel, the rear O2 looks for a high 17:1-20:1 A/F ratio. They have absolutly nothing to do with engine tuning, they just let you know when the cats arent working efficiently.

 

I finnaly get the y-pipe off with the help of a 1/2" breaker bar. I'm a strong guy and it took several tries with everything I had to break them loose. After a few nonproductive minutes I just went ahead and cut the Y at the cats. The welds are pretty well hidden and smooth aside from the splatter. Damn craftsman welder isnt very adjustable.

With it all mounted back up it sounds AWSOME!!!!! Its is a little louder but has less resonance than before. It sounds mean now, and at highway speed its got alot less drone. Its got a real deep growl. It seems to run alot better to. It takes less gas to get moving and WOT is WAY better. It pulls much harder than I can remember it ever pulling NA. Also its pulling a steady 36lbs. of air and steady 33* timing. It was pulling 32-33lbs before. The O2's were right at 890-900mv. I figured it would run better but damn. The bottom end is noticibly better, mid range is cake, and WOT screams.

Why the hell did I wait a year to do this. LOL

 

finally did it huh. i guess you bought a welder like mine. so its not loud in the cab with them off. how much louder did it get? vid time

 

Its really not much louder. Its more agressive sounding. I borrowed my in laws welder, it has a high and low amp setting and a high and low speed setting. I finnaly got a decient bead with max power and slow speed. Its freaking weak. I loved your welder. LOL I was a pro with that thing.

Its alot quieter than your truck was with the 4" catback. You would love it, its old school kinda mean. No popping on decel either. Its realy amazing how much diff it made. You gotta do it. I had to drop the trans crossmember too.