Home Brew Exhaust

[jb034]

Id say thats the set up for me then. As for the o2 sensor, it will be put right before the passenger side cat like stock?

 

[MOBS]

Id say thats the set up for me then. As for the o2 sensor, it will be put right before the passenger side cat like stock?

Wait, how many cats did your's have? Mine was a single dual in/single out catalytic converter. I just had everything from before the Y-split in front of cat all the way to dual exhaust tips removed and replaced with dual pipes running side-by-side; the O2 sensor was up on the driver's side down pipe, like 2-3feet from where pipes were cut and added onto. Where's your O2 sensor located?

 

[jb034]

Mine is litteraly right in front of the cat. Ive only got one cat after the y pipe

Also, for money purposes, should i get a di/do magnaflow instead of two si/so? would it be that much of a different system than a true dual?

And should I run all 2.5" pipe or 2.25"?

 

[MOBS]

ya ever use it as a highway racer? like 70-90 bursts of speed where you'd need the larger pipe? actually, i guess i should ask if you're planning on using the engine in the 3k+ rpm range alot....now even with the 2" pipe, mine still has amazing torque once it hits 3k, more than it did with the single 3" pipe. For instance, on cruise, it'll pull 35+degree interstate/highway hills without losing any speed in OD. So the 2.25" i would think should be fine man. You're going with magnaflow right? I'm guessing you already have the muffler chosen? If you're doing full length exhaust, and want pressures to be equalized, then go with the di/do....it'll save space underneath and is cheaper. If you dont care about equalizing pressures, or if you prefer the twin muffler look, then go with the (2) si/so.

Whatever you do, it's your truck and I wish you the best of luck. I wanna hear it when you're finished too.

 

[jb034]

Thanks man, Im gonna go with 2 highflow cats and a di/do 18" magnaflow

 

[1990GMCSIERRA]

should sound nice,,def run 2.25 or 2.5 inch pipe tho

 

[Horns]

run true duals or it was completly pointless of u getting those headers

True duals create more back pressure because you loose the scavenging effect. Duals with an H or X pipe in the middle is the best way to go.

 

[MOBS]

Horns, what about the old way of thinking that once you reach the speed of sound, there's enough negative air pressure that it SUCKS the air outta your exhaust? then ya won't need the scavenging effect....but ya may need a new paint job, i hear the air friction is extreme.

 

[Horns]

Ahahaha! Maybe we make and market a high flow vacume that sucks the air out of your exhaust!

 

[jb034]

All this scavenging talk is interesting haha but lets face it i like the idea of only having to buy one muffler. Ive made up my mind on 2.25" pipe from the headers back through 2 cats and a di/do magnaflow. Once im home from school in two weeks ill find a shop to do it and have vids up for all to enjoy!