BNK

Hi everyone. This is my first post on Yotatech forums. I recently purchased a 1988 4runner SR5 V6 4WD. It only had 109,XXX miles on it. My dad and I had the whole motor rebuilt so its like brand new. The first thing i noticed is that there is not that much power out of the V6 so i decided for my first mod, i was going to buy Downey Headers, Cross-over exhaust and a hi flow cat and muffler. The headers and cross-over exhaust piping are already sitting in my room collecting dust because i need some help with the cat and muffler selection.

I've already decided that i am going to get the Magnaflow 2.5 18" 24" (Part # is 14356). Now my question is: Is this the quietest muffler size from magnaflow for the 4runner?

Now for the car-sound (magnaflow) cat question: Do i need to by a cat with an O2 sensor boss or buy one without an O2 sensor boss? The stock cat under my 4runner doesnt have the O2 sensor in the cat, it has it in the piping before the cat. I made sure to check the cross-over exhaust for an O2 boss, but there is none on any of the piping. (Part # for the cat w/ O2 boss is 91036) and (Part # for the cat without O2 sensor boss is 91006)

Thanks for the help. After reading members post's and responses, i already can see that this is a much better automotive forum than the last one i was a part of.

Kevin

JL8Jeff

Downey sells the O2 adapter pipe that will bolt to the stock cat-back. But it necks down to 2" or 1-3/4" so I wouldn't waste time with it. You could just get a muffler shop to weld the Toyota style O2 bung into the 2-1/2" pipe that goes from the crossover Y to the cat. The cat with the O2 sensor fitting built in is for a screw in O2 sensor, the 88 Toyota uses a different style of O2 sensor. Go to Ebay and find a 2-1/2" cat for under $40 and have the O2 bung welded into the lead in pipe like I posted above. I plan on doing that sometime soon with my truck. I have the Jardine 2-1/4" cat-back and my truck seems to like it. I'm getting around 19 mpg with 32's and I still have the stock cat with 144K miles on it.

BNK

So is the the Magnaflow 2.5 18" 24" (Part # is 14356) is the quietest muffler size from for the 4runner?