FJ62 Exhaust Question

[sundaypunch]

I'm going to be replacing the exhaust on my FJ62. It's pretty much rusted out plus I have an exhaust leak at one of the downpipe flanges. Somewhere along the line my cat's were eliminated. I'm not too concerned with the exhaust being high performance as I'm pretty much just cruising back roads in a rural area. I did the search here and it seems like the most common advice is-

-Use 2.25", Y into a single free flowing cat
-Keep O2 sensors in about the same position
-Eliminate the pipe outside the frame
-From cat back use 2.5" pipe


I have a couple of questions. I stopped by my local shop today. They recommended that I use 2" pipe into a Y and then 2.25" from there back. He said without cat's it would be very loud with 2.5" pipe. I'm not sure if this will be too restrictive?

I'm also debating whether to go with a cat. or not. No emissions here but if I ever sell the truck it seems like it would be better to have one even though it's not the factory setup. The exhaust does smell really strong right now and I'm guessing part of that is due to not having the cat. Aside from extra $$ is there a big power loss if I go with a single cat?

Thanks in advance.

 

[90FJ62]

I am in the same situation. My 90 FJ62 needs new exhaust as it looks like swiss cheese.... From the info I have read running it without atleast 1 cat on will hurt the power. My plan is to keep the o2 in the stock place run a 2.5 in Y pipe to 1 hi flow cat and then 2.25 into a flow master and out behind the tire....

 

[sundaypunch]

Don't you want to start small on the pipe and then get bigger rather than go 2.5 down to 2.25 ?

 

[jharris979]

I wonder why not having one cat would hurt performance?

I talked to a salesperson at Flowmaster and he recommends the 50 series Delta Flow.

http://www.flowmastermufflers.com/50_delta.html

 

[90FJ62]

Don't you want to start small on the pipe and then get bigger rather than go 2.5 down to 2.25 ?

I thought the same thing, but was just passing along info i got from someone else. When I do mine, I will probally run 2.5 all the way back.

Dave

 

[djawahir]

I have a 50 series deltaflow on my 60 and I put 2.5" from the cat back. It sounds like a stock muffler with a little growl. I get a little more power at high rpms than I did with the stock muffler...

 

[tonkota]

I have a modified exhaust, 2 1/4" into a y and from there, 2.5" back to one cat then 2.5" the rest of the way back and out right behind the rear tire.

It's not loud at all. It sounds like a truck should sound. I really enjoy hearing it and it's not intrusive on long highway trips.

 

[bigbertha]

2.25->2.5

You want to go

2.25 downpipes->beefy y-pipe->single cat->2.5->muffler->2.5 out.

I have run without a muffler and it is too loud IMO.

I now have a magnaflow straight welded bullet muffler and it is still loud in low rpms, but not deafening. At highway speeds it is a medium hum.

If your system is too free flowing you will lose a little low end torque.

IMO what i am running is ideal. Good torque, awesome accel from stop and great power on highway...compared to crappy restrictive stock configuration.

 

[gaylonw]

I went back with Toyota stock and it bolted 'up like it was made for it'. The best I have ever seen.
Cats are nice, I put them on my Mustang Cobra, a Dakota,and a couple of Jeep Wranglers and they always seem to require mods or at least a lot of persuasion.
The Toyota stock exhaust went up EZ...........gm