Agree!
Like he said, the crossover was just the major contributor. A ding in a header tube is different than a squeezed pipe that has to accommodate four cylinders. Unless clogged, even stock cats aren’t super restrictive but I’m betting they do contribute to the loss. Have you had a close up look at your crossover? Also, he mentioned the frequent early failure of the left bank #2 02 sensor. He said they fail earlier and much more frequently than the right bank.Do you think that makes sense?
Thanks

 

I had my cats fail which lead to a reductiom in power and mileage. Did have a CEL and appkoed proper diagnosis only to realize its not the sensors but the cats. I had them replaced with HI flows while the secondaries deleted but I had the engine swapped at the same time so cant really give a objective review on the cats. I smell some gas at startup but other than that all good ( i blame the cam for the smell )

 

The downside with the MagnaFlow for the Alpha H3 is that it only gets rid of the small section of crushed pipe on the diver side, not that in front of the bolt flange on the passenger side. Still a nice improvement as it uses 3.0" pile aft of the Y point collector. I will installing mine Friday after work. It has been sitting in its box for almost 2 months cause "other stuff" always gets in the way.

 

Hey Doc,
Have you decided on a programmer to go with your exhaust etc.? If you haven’t, consider the BAMKS # 66112. BANKS folks are great and with their help, I ended up downloading SPORT 87 and using BANKSTUNE options for both engine and tranny. Since my tranny is built t0 exceed 4L75 specs, I was a bit hesitant to load their tranny tune but I did and I’m happy with all aspects. With the tune being pretty aggressive for 87 octane (about 700’ elevation here) I have chosen to run only mid grade fuel. Whatever you do, I know you’ll enjoy that super nice ALPHA!

 

Good stuff.

Yes, I saw a couple posts of yours a while back talking about the Banks AutoMind 66112... so I scored a new never used one off Ebay at a great discount when I bought the MagnaFlow Exhaust. Already have an Air Doc Intake, just need to install the exhaust and then I will try the tune.

I had the MagnaFlow cat back on my 07 since it was like 6 months old, good quality product and super easy install. Now that I am 12 years older, it will still be an easy install, just going to take a few beers longer.

Thanks for the heads up back when about the Banks Tuner. Looking forward to having the time to get it done.

 

Well, I ordered the Magnaflow kit. It should be here in time to install over the long July 4th weekend. Loos simple enough....hoping it is! A tuner to follow before too long as well, just gotta figure out which to buy.

 

Really easy install! One hint.......the original crossover is a bit hard to get out of there, so (carefully) cutting it into two pieces with a sawzall makes the job less stressful. Best of luck!

 

Thank you for that tip! I will definitely do that.

 

(Doc,
........any updates regarding your latest upgrades? One of our guys down here (will not say on the forum) is waiting to see if you give thumbs up before spending the bucks on the exhaust and maybe tuner.

 

Got the exhaust done weekend before last like I was planning, about an hour to get the old crap off and an hour to install the new Cat Back. Silicone spray is your friend..... smarter not harder. Spray up all the old hangers before you pry off the old system, spray them again and the new ones before sliding the new hangers in the rubber straps.

Basically follow the write up in Four Wheeler. See the slideshow. Sawzall the old pipe in front of the resonator, undo the clamps and remove from hangers. I did it on the driveway, stuck jack stands at the frame just in front of the rear leafs with the rear tires just barely on the ground so the old system could be removed over the axle. That Y pipe came out without much of a fight just some careful maneuvering.

I got a pic of the crushed pipe vs new MagnaFlow replacement piece at home, I'll post it soon. Haven't got to applying the Banks Tune yet, wanted to drive it without for a bit to see what just the exhaust does. Sounds great, not too loud. Like the article below says, a low burble of a note.

http://www.fourwheeler.com/project-v...aflow-exhaust/