Exhaust Mods for FJ62 (1 Viewer)

[Charlie]

89 FJ62, want to know what the scoop is on if Headers, Hi Flow Cats and a FLowmaster will improve power or do they build too much heat under the hood and create problems with the O2 Sensor and any other related smog devices. Sure would like to know what you all think

I saw the MAn-A-Fre Headers and HI Flows in their catalog, what do you think??? are they good ones or are there better??? also I'm not set in stone on Flowmaster, if they're better I'm open.

Thanks

Charlie

 

[Degnol]

Most muffler shops carry a "turbo" style muffler that does not carry the Flowmaster name. I've run them on a Yukon and now on my '40 with no problems. They're aluminized and look factory. Nice throaty sound and reduced backpressure. The one on the Yukon was $85 and the '40 was a little less. If you want to go big, get the ceramic coated headers from JetHot or the like. Run a lot cooler under the hood and as rustproof as you can get with a header. It is a lot cheaper to get the headers already coated than it is to buy them and send them off. JetHot sells headers, but so does MAF, i think,
already coated.
.02
Ed

 

[yooper]

Headers are a waste of money - they will gain you no significant performance improvements and will generate alot of heat. The stock exhaust manifold on an FJ62 is pretty well engineered. The rest of the stock exhaust system is just plain stupid, with two expensive catalytic converters and pipe that goes up and down and all around, with several sections exposed to trail hazards.

Take your truck to a small shop that does custom exhaust work and tell them what you want (see below) and they will make it happen. Don't go to Midas/Meineke/etc. as most of them can only do bolt-on work of existing parts, won't be willing to change your basic configuration (two cats, etc) and will charge you much more for an inferior final product. There are a few of these chain shops that do custom work as well and will do a good job, but only a few.

The following exhaust configuration is tried and tested on many FJ62's, including my own:

- stock exhaust manifold
- custom y-pipe into a single hi-performance generic catalytic converter (Catco makes a nice one, available from Summit Racing)
- all 2.5" pipe (if you go larger you will lose some low-end torque)
- free flowing muffler of your choice - the custom exhaust guy will have an inexpensive one to recommend
- keep everything going straight back, and keep the pipes tucked up into the frame
- reinstall the oxygen sensors in the y-pipe arms at approximately the same locations along the pipes that they were in before. If your oxygen sensors are old (more than 100K miles), replace them with new generic ones from http://www.oxygensensors.com
- tailpipe straight out the back, but cut just before it reaches the bumper, so it doesn't get pinched on the trail

good luck!

 

[dd113]

I wish I had done what Yooper has done. I kept the stock manifolds, headers are way too much money and trouble on a 62 for limited gains. 2.5" pipe back to 2 catco cats from Summit; around $90 ea then to a flowmaster also from Summit around $80. I kept the 2 into one style and it sorta sucks. I got pipes all over the place. I dont know if going to a single pipe system like his has any downsides such as loss of flow etc..... I figure OEM must be that complicated for a reason ??? I plan to modify mine to the single pipe and find out.

 

[tclndcrz]

yooper- great information man. I will eventually redo my exhaust (either doing exhaust or arb bull bar in May) and have figured i would do exactly what you just said. Im probably going with a 40 series flowmaster for the extra tone plus its not too expensive.

 

[yooper]

Hey you guys: I learned this stuff by being a member of the 3FE email list, an excellent source of info on FJ62's and FJ80's, and an excellent community of friends. Go here to check it out: http://autos.groups.yahoo.com/group/3FE/

 

[Ming89FJ62]

Put the MAF ceramic coated 3FE headers on about a year ago. So far better acceleration from the line and lots of additional heat :-[ . Damn carb cooling fan never ran before and now runs even at -10 F. I figured since the cast iron exhaust manifold needed to come off and be resurfaced (labor being a wash) I'd spring for the headers since they're a direct drop in (which they are). Probably would not do it again; I'd just have the old cast iron anchors machined and put back on. BTW MAF seems to be the only source for the 3FE headers; I ordered from JTO (instruction for a drop ship) and when they arrived they had shipped directly from MAF complete w/ RGA instructions.

Ming

 

[Charlie]

Great info Yooper & Ming !!! Thanks. I live in California and when I got my 62 smogged last year the first thing the smog guy did when he was doing his inspection was to see the vehicle had two Cats, so I'm not sure if I can go to one pipe. If anyone has done it and got it to fly, please let me know.
Also, the header issue, I've heard the same on the headers on other websites and I'm leaning now towards leaving the stock manifolds in place.

Again, thanks for the great info, this is a great website

Charlie

 

[Charlie]

Update!!, I talked to the smog referee and he looked up the vehicle and said "It must have two Cats to pass" so I called a local muffler shop that did great work for me in the past and the guy has done a few 62's. He stated he can re-work the exhaust, the new cats and new muffler so they are not in harms way.

I'm scheduled this Friday so I'll update you all on Monday

Thanks for all your ideas and help

Charlie

 

[Charlie]

Update on the exhaust mod for the 62. Express Muffler in Santee, Ca did the work and it turned out great. Learned a bit from the guy there about "Hi-Flow Cats". It turns out there are two types, one which is more restrictive and the other which isn't (Sorry I don't remember what he called them , something like one has pellets and other one a membrane, please correct me if I'm screwed up) but here's what he told me about the 62, the stock cats are the less restrictive ones so if you're thinking of putting on "Hi Flow Cats" they are same ones as the stock ones and if your vehicle has passed a recent smog test (as mine has here in California) they're still good. So it ends up all I ended up doing was getting a "Cat back" only job which included a new 2-1/2" pipe back to a Flowmaster and out the back much like the stock. I asked him about the goofy twin stock pipes that run from the manifolds down to the cats and he said they were in good shape and didn't need replacing at this time. I think I will evaulate them in the future and then post for ideas on how to make them less obtrusive.

The 62 sounds better, don't know about any additional power (will evaulate tonight when I'm driving down to the desert) and I'll update

Have a great weekend to all

Charlie

 

[fsusteve]

Years ago, I took my 62 to a muffler shop for a new exhaust, kept the manifolds, changed the rest. Threw the guy an extra $50 to cut the cats out completely (no smog test here). Noticed absolutely no difference in power or milage either, but got that pipe off under the frame finally.

 

[TJDIV]

I took my Cruiser to get the full exhaust done (headers-back) and instead of sticking with my Turbo Dual Chambers I went to Dual Chambered Flow Masters.

Now, I run this behind a SBC350, which I know makes a difference to my experience here, but anyone who says the Dual Chamber Cherry Bomb Turbo's, or any other imitation dual chamber, hasn't gone from them, directly to a FlowMaster. It made a ridiculous difference on my Cruiser. The biggest difference actually, of any of the aftermarket stuff I did.

I know an SBC is different, but if you get even a fraction of the difference between mufflers that I got, it would be worth it ten times over to spend a little extra dough.

Or, play it cheap, realize it's just not what you wanted, and then up-grade.

 

[dd113]

I was at an exhaust shop today with another 62 and the owner got it on the rack for me. I explained some of the issues and complications. My idea was to get 2 cats back in between the frame rails then back to my flowmaster. He said he could do it but offered a better suggesstion that I did not even know existed. 2 down pipes with stock o2 locations to a dual inlet/dual outlet cat. One cat body with 2 internals. He claims it will be considered the same a 2 independant cats for SMOG police. It goes from there back to the flowmaster with dual inlets and single outlet.

His idea allowed for the stock or better flow and back pressure. he said that going with a single cat would not allow enough flow. I dont know if this is true but he sounded convincing.

The 2 in cat installed with dicking with the pipes and using existing muffler would run around $375 with the new cat taking up $300 of that.

 

[Charlie]

Report on the "Cat Back only" work. We'll I went down to the desert this weekend and towed my 16ft enclosed trailer with my quad in it. The last trip I did with this set up, I had to go to first gear (25Miles per hour) climbing the grade out of Borrego Springs (East of San Diego) this time I climbed out around 30 (2nd gear), so no big change and (totally un-scientific example) but the what I did notice is the temp gauge stayed in the middle the whole time I was climbing. (not sure if ambient was cooler but I was liking it). The 62 ran great !!!

Thanks

Charlie

 

[yooper]

[quote author=dd113 link=board=1;threadid=11258;start=msg105122#msg105122 date=1076822758]
I was at an exhaust shop today with another 62 and the owner got it on the rack for me. I explained some of the issues and complications. My idea was to get 2 cats back in between the frame rails then back to my flowmaster. He said he could do it but offered a better suggesstion that I did not even know existed. 2 down pipes with stock o2 locations to a dual inlet/dual outlet cat. One cat body with 2 internals. He claims it will be considered the same a 2 independant cats for SMOG police. It goes from there back to the flowmaster with dual inlets and single outlet.

His idea allowed for the stock or better flow and back pressure. he said that going with a single cat would not allow enough flow. I dont know if this is true but he sounded convincing.

The 2 in cat installed with dicking with the pipes and using existing muffler would run around $375 with the new cat taking up $300 of that.
[/quote]

Sounds unnecessarily expensive and might possibly still make you fail, depending on which knucklehead off the street is doing the inspection that day (no offense meant to any Cruiserhead emissions inspectors out there, although I doubt there are any). Why not just go with two cheap free flowing aftermarket cats rather than the expensive and complex dual chamber one, and while you're in there spending money on pipes, replace the old muffler with something better? My muffler was like $50 and flows way better than the factory one did. I think my cat was $100 at the most.