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Smithers
01-03-2010, 10:47 PM
I thought I should go ahead and start a thread for my headers and exhaust. This is a pretty hot topic and I don't mind sharing. It's such a labor intensive process that I recommend anyone attempting this kind of work make friends with professionals in their area that do this type of work. I didn't do this all myself. There are much better TIG welders in my area that were happy to help out. I'm "ok" at welding but learning to do precision TIG welding on curved surfaces is just banging your head on the wall. So enjoy the pictures and I hope they give you some ideas on how to arrange your own exhaust system on your 1UZ-FE powered project.

I'll be posting pictures later. I have detailed pics of working on the headers to get them to wrap around the steering shaft and also to point downward from the collector in order to point down before the firewall. I'll also make sure to get some good video and sound of the music it will put out. :D

Smithers
01-17-2010, 02:08 AM
Not sure if I want to do the side exhaust thing. It would probably be louder compared to having these mounted inside of the frame which is something I'm not really going after.

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_03.jpg

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_02.jpg

Smithers
01-17-2010, 02:14 AM
Messing around some more. I'm kinda leaning towards putting them on the inside of the frame and having them slant downwards. I would like to put a down tip on the ends of them but that would just take more time.

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_04.jpg

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_05.jpg

Smithers
01-17-2010, 02:21 AM
Just getting things in a pile ready to begin piecing things together tomorrow. And yes these mufflers are Aprilia 2.5" titanium motorcycle mufflers. I used to run one of these on my streetbike. I replaced it with a carbon fiber one and I always knew I would find a good use for it one of these days!

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_06.jpg

Smithers
01-17-2010, 10:58 PM
It was raining this morning but that's not stopping me from working on the last chapter in this V8 Tacoma build. I went over to my good neighbors house and borrowed his chop saw and went to work. The goal with this system is to keep it lightweight and simple. If I really like the sound of it then I'll weld some outlets to the ends of the cans and run those back down the frame and then over and have them dump out in front of the rear wheels. But for now I want to make sure they work ok.

Cut a couple radius's, tack'd em up and all ready to weld them up.
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_07.jpg

And the end result
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_08.jpg

Smithers
01-17-2010, 11:05 PM
And here is a shot showing the general angle that they had to be made to follow. On the drivers side the one side must go out and around the transfer case a little more and the fuel tank limits how far back I could run it. I have these tucked right up close to the cab so that there is NOTHING hanging down below the frame. A great benefit of the cab lifted a bit off the frame is that I can raise everything up and after I build a new cross member for the transmission there won't be anything hanging down past the frame so I could seriously build a flat belly pan/ skid plate like an RC or race truck. I'm sure that would afford me a couple more MPG which would be a fun experiment... in all my free time, yeah right.

These pipes don't weigh hardly anything! The next time I have these off to weld on the hangers I'll put them on a scale.
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_09.jpg

Smithers
01-17-2010, 11:09 PM
Here is a shot showing everything underneath now that I'm nearly ready to roll. I'll be building a trick heavy duty crossmember sometime soon and I'll just extend the posts up on the crossbar that is closest to the camera in this picture. I had to put this patchwork crosspiece in a long time ago because jumping the Tacoma and offroading it hard causes the cab to sag in the middle. The best way to fix this is with a whole rollcage that is welded to the body at the top and bottom. I'll have to fix it the right way this summer. :D

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_10.jpg

Smithers
01-17-2010, 11:15 PM
Also you can note the transfer case that is offset to one side. This is normal and you can also see how I moved the whole transmission and case upwards a couple inches above the stock location. This is why I'll be fabbing a new crossmember to allow the whole mounting system to be between the main frame rails and not hang down underneath it. This arrangement worked out great because it allows for the best positioning of the V8. Factors in the exact engine placement include, being able to have room for the front sump oil pan, being able to still remove the oil drain plug from that pan, being able to use the factory oil filter mount, the wide overhead cam heads will interfere with the shock towers, the two piece drive shaft is very well built and allows for great flexibility, room for exhaust headers, room for ventilation around the front and rear of the engine and a few other things that I'm sure I left out.

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_11.jpg

Smithers
01-17-2010, 11:20 PM
Passenger side view. I can't be happier with the amount of room I have to work in around the engine and exhaust. I hated those fenders but of course I'll have to make some custom aluminum ones in the near future. This project will probably never end. :\

As soon as the engine fires and runs in a somewhat normal state of tune I'll quickly size up the wiring harness and clean all of that spaghetti up nice and tidy. Of course I need to go buy a handful of weather proof fuse holders and a spool of heat shrink.
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_13.jpg

Smithers
01-17-2010, 11:24 PM
Without the wires on the drivers side it looks much better. All you can see are fuel and brake lines. I really need to reinforce the spindles. I can't believe they have held up all these years!

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_12.jpg

jdmhn8
02-18-2010, 03:17 PM
I really like this independent setup, but it looks like you have a ton more room in front of your gas tank up to the header down pipe than on a 4Runner. Don't think there's enough room for a cat then muffler this way.

Where's your fuel filter at? Is there any issue with having mega hot exhuast pipe near the fuel lines?

Smithers
02-18-2010, 04:23 PM
Well I'm getting exhaust gas in the cab so I am changing things here real soon. I haven't been driving it hardly at all cause I need to tune the computer and build a real exhaust. It sounds awesome though. :)

On the 4 cyl Tacomas the fuel filter is bolted on the engine right up against the intake manifold. So I simply moved it up and mounted it to the wall on the drivers side. The truck has so much air running under it heat isn't an issue even when the exhaust is so close to the fuel lines. It would take some catastrophe for anything to happen with the fuel. The lines are super strong and bendable for safety reasons. Hopefully soon I'll have time to build a header back system with the new Tundra muffler I have waiting.

Jay351
02-24-2010, 03:53 PM
Make sure you get a video clip with the muffler, so we can hear that thing sing!

Smithers
02-24-2010, 05:11 PM
Oh yes I'll get more video. Here is all I have so far just incase anyone missed the first good one. :]

-8grTIRTG3w

Smithers
02-25-2010, 12:34 AM
So tonight I worked late when I had a chance just to get this thing closer to being a daily driver. I just continued on from the back of those mufflers and made some pipe to go over the carrier bearing crossbrace and then made a y-pipe to join into the Flowmaster muffler I had behind my old engine. The stock Tundra muffler was just too long and would have been a really tight fit but the smaller Flowmaster is an easy fit. Making the Y was a chore but I just made a rough one to get the thing installed and on the road. I was shocked at how much quieter it is now. Oh well I just need to be able to drive it comfortably which it sure is now.

Nice and simple.
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_16.jpg

So I guess this is my street exhaust system and I'll be building a different one that is louder when I go ahead and build the roll cage. It's really quite nice driving a quiet truck and you can definitely still hear the engine. I'll just be adjusting the clutch so I can get on the gas now and see what it's got.

The Flowmaster Muffler hangs exactly where it did behind my 4 cylinder.
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_15.jpg

Smithers
02-25-2010, 12:51 AM
It was a last minute thing to go ahead and finish the exhaust tonight but I had to. It's been miserable not being able to drive this thing. The short exhaust would instantly just start spewing fumes into the cab and the sound was incredibly loud so I had to tip-toe through town. As soon as I would give it any throttle it would crackle and just make sounds you could hear for blocks. It's definitely strange now that it's quiet. I must admit this muffler is cutting down on some flow so I'll be deciding on another muffler to throw on there later on. Maybe a larger Flowmaster. The Flowmaster brand is the only muffler that lasts. All the other brands I have tried just break off really quick when you start getting crazy offroad.

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_17.jpg

And my friend really likes to get up close when he welds! He doesn't realize how close he's getting so I need to show him this picture so that he backs up from now on. This isn't good and it's splattering back onto his brand new helmet.

This is way too close! :)
http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_18.jpg

Smithers
02-25-2010, 08:50 AM
And while we are on the subject: A PDF with some info on how to make power out of your exhaust system. These are just things that exhaust fabricators think about all the time. Most people don't realize the science behind building headers or an exhaust system but this will help show what kind brain work goes into a proper system.

Headers, tube size, collectors, X-pipes and more exhaust technology summed up in a brief article here in this exhaust system PDF. (http://www.fourwheelperformance.com/phorum/ex_articles.pdf)

Smithers
12-05-2010, 09:58 PM
Hmmm I need to update this thread. I put that Flowmaster on and it created some back pressure which caused the Aprilia mufflers to absorb almost ALL of the sound. It really sounded like a Cadillac or some luxury vehicle. It was so quiet and soft which would make a great exhaust for a road trip. What I ended up doing it cutting off the Flowmaster and just adding an extension tube to dump the exhaust further back without muffling it. This created just enough back pressure to allow the race mufflers to absorb some more sound. It's perfect now. I can let off the throttle and drive normal to keep the sound down but when I put my foot in it the decibels crank up for sure. This is pretty crude for now but once the roll cage is built I'll probably change most of the exhaust layout anyways so I didn't need to spend time making it pretty for now.

http://www.fourwheelperformance.com/1uz_tacoma/1uz_exhaust_19.jpg

Here's a video to demonstrate:
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