Mufflers, Cats and Welders oh my!

[WJM]

Ok....so back in the day before my 5SPD and 4WD conversion...i was running the stock EA82T with a 3AT....i was getting 22 mpgs driving somewhat normally....

 

Cut the intake, hack the muffler....gut the cats and run nothing but the DP....24 MPG's doing whatever I want...mostly WOT tho.

 

Skip on to the 5spd conversion and the 9.5:1 engine, and a similar exhaust....no cats once again...29 MPGs....increase mostly due to 5spd.

 

Now...on to dragging some 4wd components....28 mpgs.

 

Now...onto FT4WD!! 28 MPGs on any given day.

 

Now...onto an emissions legal exhaust...both cats and a muffler. Back down to 24....

 

Now...no muffler! 26!

 

Now....back to exhaust before emissions....back to 28.

 

Ok...so the 9.5:1 engine gave up....back to 7.7:1 and cat'ed exhaust, but no muffler....to 26-28 MPGs.

 

Now...onto cats and stock style muffler....22! WHOA. No way. Also, going from open back to OE stuff....throttle responce down, turbo lag comes back...and most notibly, the MPGs decrease. Which is a BIG deal considering the price of gas and I ALWAYS run 93 octane in it...more on that later.

 

So...gutted the DP again, and put a DP-back large diameter with gutted cat on. Ahhhh.....there we go, my noise is back, so is the power. Now lets see about the MPGs since Ive not run a size of pipe more than stock. The DP i have has been redone from the cat back to the second cat...and from the 2nd cat back, its 2.25 inch exhaust. Lets see what happens on the I-state now.

 

Now onto fuel.....

 

I ran 87 for a tank ful since i am doing ALOT of driving cuz I have to move back into my parents place....nope, never do that again...the fuel that is. Power was DOWN DOWN DOWN...even after palying with timing again. The engine pulled, but was WEAK!! Could barely get the rest of the wagon going to pass someone...DOWNHILL!! Ok...93 back in...WOW...what a HUGE difference. PULLS like mad now, especially with the stright thru exhaust restored.

 

So...note to all turbo people...stright pipe TBE and 93 (or highest octane possible in your area) fuel and you'll get some MPGs and HPs over stock for sure.

[baccaruda]

I found out part of the power loss problem on my wagon was due to the turbo flange having separated 75% from the rest of the crossover pipe! got that out and welded up (for free, thanks to Guy @ Muffler Mart) and will go back in soon. wagon should be a little more responsive. too bad this doesn't fix the half compression issue... this means I'll want to tweak the timing and run premium in it, as I have 2.5" open exhaust all the way.. thanks will!

[WJM]

yeah...ive found out over the course of THREE (3) crossover pipes...that when they break....power is no more.

[86subaru]

i have a 88 turbo a/t full time 4wd wagon w/ 88,000mi , i get 23 city 28 hi way, big cat cut out ,2in pipe all the way back turbo muffler , i run 87 octine , but i may try a tank of 93 or 94 from shell ,

[theDirtyRue]

How hard/easy is it to gut a cat? I'm running a glasspack for a muffler after no muffler for a while, and i saw a pretty big loss in the power. Anything else thats an EASY fix for better fuel efficency? I drive a lot and i dont make very much:( .

 

Thanks,

[WJM]

EASY to gut the second cat....long metal rod and a hammer...might need some long needle nose plyers for the mesh stuff.....the first cat...need to hack the 'neck' off neatly right at the cannister....easy'est to use a long llong drill bit and drill it out....or can use the punch out trick as used for the second cat.

 

Now the hard part....you have to WELD the neck back onto the cannister JUST RIGHT or the DP wont bolt back up right....luckily Ive done this several times so I can do it blind folded almost...and it helps that I have a welder at home now.

[The Scooby]

EASY to gut the second cat....long metal rod and a hammer...might need some long needle nose plyers for the mesh stuff.....the first cat...need to hack the 'neck' off neatly right at the cannister....easy'est to use a long llong drill bit and drill it out....or can use the punch out trick as used for the second cat.

 

Now the hard part....you have to WELD the neck back onto the cannister JUST RIGHT or the DP wont bolt back up right....luckily Ive done this several times so I can do it blind folded almost...and it helps that I have a welder at home now.

all i did today was use a cutoff wheel on a dye grinder at Aaron's, cut off the bottom heat sheild, just the tack welds, then cut a large C in the bottome, then just hammered a long flathead screwdriver and put it through about 4 times and it all fell out, then got the needle nose and pulled out the mesh.

now i just have to weld it back up as well as the flange tot he DP itself where it bolts to the turbo, its cracked almost 50% around the pipe, so looks like i got to do that also now.