OK, So Bill (the Local Exhaust shoP) Put a 2.5 inch Flowmaster Cat on right at the Y-pipe, and I think (He said he was going too anyway) put the O2 sensor right between the Y & the Cat. Then 2.5 in stainless about 3.5 feet of it the a Flowmaster Standard 40 then 2.5 in stainless tail pipe and the 2.5 inlet - 4.5 outlet chrome tip...
Here's the results:
1. The 3.slow sounds like a 1972 L-88 corvette. Sounds very sweet, but way to loud. I have 800 watts of bass, and it screws with it. It definately sounds like there is a well tuned V8 under the hood. The 18 - 30 year old crowd would love this thing. sound like a riced out chevy small block. (I'll try to record some Sound data and Post it)
2. Lowend Torque beyond compare. This thing is a low end monster.
3. However, at 70 she's about done. There is no topend get up at all. It will get up to 70 with the best of them. I even got the 4high 4 wheel barker out of it with the 31x10.5 Dueler H/Ts made marks with all 4 of them at the same time. But at 70 I matted it and got 80 about 10 seconds later... It was crapped out at 70... I'm guessing that there is to little back pressure at the high RPMs.
4. With that in mind, At 70 I normally run about 3K RPM before the K&N Drop in, and the exhaust. Now I'm about 2.5K to 2.6K at 70....This may be a week O2 sensor maybe? It may be that the O2 sensor is dirtied up from 12 years of use, or just plan worn out after 195K miles.
That's the results... Now the next step. After, doing what I should have done in the first place, Calling Flowmast Tech support. They are very helpful folks. You tell them what you have, and what yoou want and they will tell you how to achieve it... SO I called Bill, and told him that that 40 was just to much interior resonance for a middle aged guy to have going on. Then that I wanted to replace it with a 2.25 in stainless from the cat to the muffler, and a series 50 delta flow 3 chamber 2.25 inlet/ 2.5 outlet. He said that he had told me that it was going to be loud. I agreed and explained that I was pretty stupid, and did not mind paying him to for my stupidity as long as he was not punishing me. He said fine, that will be $75 for the muffler, 2.25 stainless, and the work. I said that sounds like a great deal, and if he were to Saw-all the muffler I could probably sell it, and recoup alittle of my stupidity. He said fine, and 1 week from Monday he would be ready becouse he had to order it, and would be closed all next week anyway. Bill is like semi retired, and s pretty good guy to I would say.
The guy at Flowmaster said that no matter what you should never go with anything bigger than 2.25 on the 3.slow 4Runner becouse it needs some back pressure, and any bigger will release to much. He also said that the header were only needed if you were going to be pulling stuff, or 4x4, or crawling or like that. I plan on driving to and from work mostly with some additude ,the occational trip to the dump with the trailer, or hauling my bike or tractor on a trailer. He said the same about the full cold air kit. He said the drop in K&N was some pretty serious intake flow. I'm replacing the O2 sensor as well. I'm also going to ensure that the MAF Door is functioning well.
I'll get the results out when it's done... of that..
My friends chevy with true duals doesn't have an h pipe so he gets an odd noise and its not even and I'm sure he's lost a little torque. I really want to run true dual's so I've had a little time to think about what i would do. Howevery I'm not looking to experement with my only ride. So maybe someday.
