Exhaust Pipe and big improvement

Romer · 10-11-06, 10:14 PM

I had some damage from Flat Nasty with some of my exhaust hangers and a section of pipe that needed to be replaced. We (the shop) replaced the 2.5" section between the cat and muffler, didn't want to do anything to mess up the O2 sensor.

I previously had replaced the muffler with a Magnaflow.

The pipe from the muffler back got replaced with a 3" pipe (vs. the 2.5") and I had the resonator (spell??) removed. I also angled the tailpipe out behind the wheel so it would not get scrunched by the bumper again.

The Toyota installed pipe had an area where it was routed above the frame that was pinched that brought it down to about 1" there. The tech said that was from the factory and several of my friends said they have the same thing. They did this to make it easier to route the pipe.

Well the 3" pipe fits in that area without have to crimp it if you make the right bends before and after. It's tight, but does not bump anything.

So I removed the restrictive pinch above the frame. Replaced the 2.5" from the muffler back with 3" and lost the resonator.

Boy can I tell the difference. Not sure if you could on one that isn't supercharged. It's much quicker on the pickup.

I didn't have my camera at the muffler shop, so I don't have any pics of the pinch.

Simple, cheap mod that I would recommend. Was thinking of doing some kind of custom exhaust, but with the 3" pipe and the Magnaflow, I feel I have reached all the customization required.

jamisobe · 10-12-06, 06:12 AM

Try swapping out the two stock cats for 1 high flow dynatech. I also went with 3" pipe from the headers back tucking all much higher up under the body and next to the frame. I noticed a significant difference in power. I am starting to wonder about adding one of those superchargers. Was it tough to install?

Romer · 10-12-06, 07:22 AM

I had someone do it. Didn't look to difficult, The crankbolt I'm told can be a PIA

fzj80kidpen · 10-12-06, 07:30 AM

Romer,
I would really like to see a pic or two of the tail pipe routing. Mine is on it last days. Resonator is gone and it is cut all the way back to where the bend beside the tire is. I do not like the way the exhaust goes under the frame rails. Just seems like it will get smashed and I would like to avoid going that way. What model of magnaflow do you have and how do you like the tone. I can barely tell the resonator is not there only when the radio is off. When its on I can not tell.

Romer · 10-12-06, 07:34 AM

It is throatier (is that a word), but I like it. I'll snap some pics this weekend and add them to the thread.

DanKunz · 10-12-06, 07:35 AM

I am soon to do this as well...my between the cats flange is well bent and leaking. I also have an aftermarket muffler and a juge rattle from broken hangers, etc.

DTAYLOR · 10-12-06, 08:21 AM

Quote:

Originally Posted by Romer

I had some damage from Flat Nasty with some of my exhaust hangers and a section of pipe that needed to be replaced. We (the shop) replaced the 2.5" section between the cat and muffler, didn't want to do anything to mess up the O2 sensor.

I previously had replaced the muffler with a Magnaflow.

The pipe from the muffler back got replaced with a 3" pipe (vs. the 2.5") and I had the resonator (spell??) removed. I also angled the tailpipe out behind the wheel so it would not get scrunched by the bumper again.

The Toyota installed pipe had an area where it was routed above the frame that was pinched that brought it down to about 1" there. The tech said that was from the factory and several of my friends said they have the same thing. They did this to make it easier to route the pipe.

Well the 3" pipe fits in that area without have to crimp it if you make the right bends before and after. It's tight, but does not bump anything.

So I removed the restrictive pinch above the frame. Replaced the 2.5" from the muffler back with 3" and lost the resonator.

Boy can I tell the difference. Not sure if you could on one that isn't supercharged. It's much quicker on the pickup.

I didn't have my camera at the muffler shop, so I don't have any pics of the pinch.

Simple, cheap mod that I would recommend. Was thinking of doing some kind of custom exhaust, but with the 3" pipe and the Magnaflow, I feel I have reached all the customization required.

Romer,

This sounds like a most excellent mod! I would love to see some pics. Can you also outline / break down the cost? I'm also planning a Supercharger in the late winter or early spring (depending on cash flow).

Thanks,

Dan

Romer · 10-12-06, 08:26 AM

The cost to replace the pipe from the muffler back was $175. I bought the muffler a while ago and can't remember that. Don't even remember the model number off the top of my head. I think I have the receipts, so when I take pics I'll post that info as well.

How much was the Dynatech cat?

jamisobe · 10-12-06, 08:34 AM

Quote:

Originally Posted by Romer

The cost to replace the pipe from the muffler back was $175. I bought the muffler a while ago and can't remember that. Don't even remember the model number off the top of my head. I think I have the receipts, so when I take pics I'll post that info as well.

How much was the Dynatech cat?

The Dynatech cat was 170 from Summit.

http://store.summitracing.com/egnsea...=KeywordSearch

Romer · 10-12-06, 01:55 PM

Did you have to do anything special with the O2 sensor?

jamisobe · 10-12-06, 02:01 PM

Quote:

Originally Posted by Romer

Did you have to do anything special with the O2 sensor?

We installed the forward, pre-cat O2 sensor in the flowmaster y-connector. If you look closely in the pic you can see a wire barely looping down from behind the y.

Jegs had an O2 sensor nut to weld in.

Romer · 10-13-06, 07:01 PM

Here are pics of the routing of the pipe over the Frame. It comes out the back behind the tire. I might cut that back and angle it down though (Christo's suggestion)

It's crimpes a bit over the frame, but there is at least 2" of flow vs. the 1" crimp that was there.

jamisobe · 10-13-06, 07:37 PM

3" pipe w/mandrel bends... http://www.man-a-fre.com/pa2/3inchce...ackexhaust.htm

Information obtained at the time indicated that with the headers, high flow cat, and custom collectors 4.5 liters is the minimum displacement for 3" back without having a negative effect on low end response. Higher RPMs is where I feel some nice pull.

Like my Eastern Ohio/West Virginian clay coating?

jamisobe · 10-13-06, 08:00 PM

Here is my choke point. Attica, IN was a little rough.

I recently found someone who can help me with fabrications in San Antonio. I need help fixing this and a couple of other things. Good help can be hard to find.

RavenTai · 11-03-06, 01:16 AM

Edit: oops wrong thread

Koffer · 11-03-06, 08:56 PM

Quote:

Originally Posted by Romer

Here are pics of the routing of the pipe over the Frame. It comes out the back behind the tire. I might cut that back and angle it down though (Christo's suggestion)

It's crimpes a bit over the frame, but there is at least 2" of flow vs. the 1" crimp that was there.

Ken
You better do something about that brake line as its getting too hot and melting like

Romer · 11-03-06, 09:03 PM

Good catch, I will take care of that.

I have decided it's probably louder than I like and will eventually put a glass pak or turbo muffler in series to see how that does.

cruiserland · 11-29-06, 07:53 AM

I replaced cats with 1 high flow and went over the frame with 2.5 inch into a dynamax muffler
cat lasted six months, where upon inside desintigrated
removed guts and put back on
sounds like muffler is wasted now, truck is unbearably loud,even put resonator back on which helped a little

would like to find replacement muffler that is not loud and would last
tried FM big block stainless before dynamax, that was insanely loud, sounds great on 2F in 60 tho....

whats the best muffler for the 80 (1996)?

Romer · 11-29-06, 07:56 AM

I plan on adding another high performance muffler (Turbo or galsspack) in series. Did something similar with my 40 and it worked great with out reducing performance.

locrwln1 · 11-29-06, 08:06 AM

Romer,

Slight thread hijack, but did you ever post up your gas mileage after SC install? I was wondering if it went down, stayed the same or improved slightly. I know you have moved up in tires and soon to be gears, but when you were still stock gears with 285's what were you getting for gas mileage?

Thanks,
Jack

Romer · 11-29-06, 08:30 AM

Before SC I was getting about 14, after SC I was getting 13.5. Thats a mostly city driving

locrwln1 · 11-29-06, 09:20 AM

Quote:

Originally Posted by Romer

Before SC I was getting about 14, after SC I was getting 13.5. Thats a mostly city driving

Thanks,
Jack

sseaman · 11-29-06, 10:05 AM

any body have an idea on size of pipe for a 3fe? would 3" be to big?

jamisobe · 11-29-06, 03:23 PM

Quote:

Originally Posted by sseaman

any body have an idea on size of pipe for a 3fe? would 3" be to big?

This is a good link that will provide some discussion and reasoning that could help you with your question.

The key is to keep your exhaust hot as it leaves your pipe with as little restriction as possible. If you 3fe is really cranking 3" may work. Otherwise, it may hurt performance as your exhaust begins to cool too much before it exits.

ginericLC · 11-29-06, 07:51 PM

I went 2.25" on my 3FE. No cats. It made a huge difference. I went 2.5" on my 94 and I'm not as satisfied with it.

jamisobe · 11-30-06, 02:30 AM

fixed the link.

Lockd97 · 11-30-06, 08:31 AM

Has anybody thought/tried this?
Seems expensive for the oval tubing but I like the idea of not losing cross section.

jamisobe · 11-30-06, 08:51 AM

Quote:

Originally Posted by Lockd97

Has anybody thought/tried this?
Seems expensive for the oval tubing but I like the idea of not losing cross section.

Good post. I may have an idea to make that piece work if I reroute my exhaust between the muffler and the cat. Ihaven't delved in that deeply to know if it would be neccesary.

Bear80 · 11-30-06, 02:15 PM

jamisobe -- so are you in San Antonio, if so we should meet up some time since the LSLC chapter down there is no more.

Anway, with that new cat you put in, did you have any issues with the rear O2 sensor throwing codes?? I want to do somthing similar so I can get the pipe routed over the frame like the '93/'94s.

jamisobe · 11-30-06, 02:44 PM

Quote:

Originally Posted by Bear80

jamisobe -- so are you in San Antonio, if so we should meet up some time since the LSLC chapter down there is no more.

Anway, with that new cat you put in, did you have any issues with the rear O2 sensor throwing codes?? I want to do somthing similar so I can get the pipe routed over the frame like the '93/'94s.

No code throwin'.

We used new sensor nuts from Jegs in locations similar to stock. Everything worked fine. I will say that I had to replace one of my 02 sensors previously.

I'll pm you regarding meetin' up sometime. How often are you in the San Antonio area?