homewrecka

Hello all! I have a 89 v6 4runner. It is a project in waiting. I purchased a set of Downey headers for it. Where I live, it seems that alot of people favor Flowmaster mufflers. Don't get me wrong, I have nothing against them but, I would really like to give Magnaflow a try. My question is. How would a dual exit exhaust compare to a single? Should I go with a single or double exit setup? Please help!!! Any and all info/ help will be greatly appreciated. help, help, help...

CoedNaked

Running a dual exhaust on these trucks is virtually impossible. Put your truck up on a lift or go under your truck and try and picture a 2" pipe running down the right side of the underbody by the gas tank, etc. Too hairy. Besides there isn't much data on this being done properly, and I don't think the 3.0 puts out enough air to warrant needing a dual exhaust unless you went to really small pipes. Cost wise, and logistics wise, I think you're better off with sticking to a 2 1/4" straight single pipe out the left side. Have a custom crossover made if the Downey stock one doesn't work. I would personally run a 2 1/4" pipe after the two pipes join, as long as it's mandrel bent or welded mandrel bends. If not then consider running 2 1/2" pipe if it's pressure bent.

As far as muffler choices go well the sky is the limit. It think someone said there is one flowmaster muffler that has a single in/dual out design. That might give you the effect of a dual exhaust as far as looks go, and supposedly it's nice and loud which some guys like. I don't think you could go wrong with any of the mufflers out there really - give Borla some consideration though, and really put some though into what type of pipe you're going to run after the headers (mandrel bent, crush bent, 2 1/4" or 2 1/2"?).

rockota

Duals on a 3.0? Not a good idea.
Run the Downey's into a free flowing Cat into a mild muffler all w/ 2.25 or 2.5" tubing and call it good. I have the magnaflow, I think it's too loud, especially w/ the top rolled up.

89red4x4yota

i have the flowmaster muffler with a custom 2.25 catback, single. i like it i think its just right for the 3.0, i have the least amount of bends possible, i think three total (after the cat) sounds good two. i agree with the rest of the guys if you want the dual look get the dual exit muffler, the dual exits are for the look the don't do much, maybe a bit louder

1985 4Runner

I had duals on a 89, but it was all custom work, split after the cat. Sounded great, no gain or loss in performance for about $350. Go to a shop that does exhaust only & ask around.

Sonofmayhem

if you do dual go single till the rear end and dueal it out. its really good looking, but i like my side swept dynaflow it sounds narly too.

homewrecka

Hi guys!
Thanks for the replies! I intend to use 2 1/4 pipe on my exhaust system. Rockota, you said that you used a freeflow cat. Was there a certain brand that you used (catco,magnaflow, etc.)? I was told that Magnaflow part #11225 was the muffler to get. I believe that I got that # from the exhaust write up somewhere in this forum. Anybody got any other suggestions or useful info that I may be able to use? Thank you all so much for your help. I really appreciate it!
Mike

MadCityRich

I'm happy with my 2.5 inch non-mandrel bent exhaust. I replaced the cat and everything back of the cat. Noticed a mild gain across the rpm range. I ended up with a Flo Pro muffler. Supposed to be like Flowmaster. It's pretty loud, but I don't care.

MadCityRich
'95 3.0 4x4 PU
Man hubs
4.88 gears