1HD-T 3" straight piped. Post install thoughts

Cruisin'

Out in the shop, building something cool!
 
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Well, my stock exhaust started to rust out near the flex joint at the front, so that was all the excuse I needed to redo the system from the turbo back :D After reading some threads about exhaust noise, and straight piping a turbo I decided to go for it. Bought a 3" flex joint, a few flanges and gaskets, a 7' length of 3" pipe, and a mandrel bent 'U'. Around $170 all in.

I figured it would be simpler to run the new exhaust down the outside of the frame, and put the outlet just ahead of the rear tire. What with already having sliders on, this proved to be a tighter fit than I had expected, but the straight section fit, so it was just a matter of getting the elbows to line up, and fabbing a couple of custom mounts using the original Toyota rubber isolators.

The noise level was slightly higher than I was expecting, though at cruising speeds its barely louder than stock. Sounds throaty when you step on it though. And I love hearing the turbo spool up:grinpimp:. The best part was when the :princess: took it to the grocery store and came back saying "its not that bad, besides it's a big burly truck, it's supposed to be kinda loud". And that's why I love her:cool:

And now for what you've all been waiting for... Pics!
Down Pipe.jpg
Straight Pipe.jpg
Outlet.jpg
 
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like it!
How far inboard is that down-turned tip? Seems like it could be a rock/branch grabber. And a warm one at that (I worry about dried twigs igniting a field fire around here)

I'm pleasantly surprised that it fits so well outside the frame rails.
 

Cruisin'

Out in the shop, building something cool!
 
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like it!
How far inboard is that down-turned tip? Seems like it could be a rock/branch grabber. And a warm one at that (I worry about dried twigs igniting a field fire around here)

I'm pleasantly surprised that it fits so well outside the frame rails.
The turn down is just inside of the slider. It only sticks down a little over an inch. Its somewhat protected by the slider, and the suspension arm behind it. If it becomes a hang-up I can always weld a guard to the bottom of the slider to protect it.

I'm not too worried about starting fires... Most of the year its somewhat damp (or downright soggy) where I live.
 

Cruisin'

Out in the shop, building something cool!
 
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Forgot to mention in my original post the performance improvement with the opened up exhaust. Get-up-and-go off the line is dramatically improved, and it takes less throttle to maintain speed on the highway and up moderate hills. Definitely a noticable improvement in power and throttle response. Based on the two tanks I've been through since doing the job I've seen a little over a 1mpg improvement in fuel economy also. More power and better fuel economy... NICE!
 

Cruisin'

Out in the shop, building something cool!
 
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I'd love to hear it on a video. Do you have any smoke issues, asking 'cuz my 81 is quite smoky.
I don't have any video, but I'm hoping to get out for a club run or two in the spring, you can hear it in person.

Mine doesn't smoke too bad, so its not a big issue. It is best to have the driver side doors closed for the first puff when you start it though.
 

Cruisin'

Out in the shop, building something cool!
 
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do you think you could have made the turn-down more flush?

am I making a mountain out of a mole hill?
The picture was taken from quite low. It looks like it sticks out more than it does. I wanted to try to get the tip out into the air flow at least a little. But yeah, its kind of a mountain out of a mole hill thing. I guess I'll find out when I get out wheeling:meh:
 

romey

 
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great job cruisin! hey, did you play around with the boost? up to 14psi is what i keep reading with the 3" exhaust... or you just left it alone?

and a nice shot of those purdy sliders you got there...;) looks beefy!
 

Cruisin'

Out in the shop, building something cool!
 
Joined
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great job cruisin! hey, did you play around with the boost? up to 14psi is what i keep reading with the 3" exhaust... or you just left it alone?

and a nice shot of those purdy sliders you got there...;) looks beefy!
I've yet to mess around with boost or fuel settings. I don't want to start changing anything there until I get boost and pyro guages installed so I can keep an eye on things. I'll have to get funding approved by the :princess: for that. The exhaust was easy, the old one was going swiss cheese.

Gold Boy,
I considered if I should do side exit. I know I'm not the only guy in the lower mainland running this way, but if push comes to shove and I have to change it, its just a couple mandrel donuts and a weekend's worth of :wrench: and it sticks out the back of the truck again.
 
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Another take on a 3" side exit pipe. The lowest point of the pipe is actually no lower than the chassis rail but then I do very little off roading so not even an issue. Sounds 'NICE' ;)

 
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I don't want to call you a liar-- but are you sure that muffler doesn't extend below the frame rail? Looks really low from the photo.

But most important: if it works well for your purposes, then it works!
 

Cruisin'

Out in the shop, building something cool!
 
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Towpack,
Yours is spiffy and shiny looking and worthy of display. Nice job.
Mine is a chunk of steel pipe and worthy of being hidden. Above the slider worked nicely!
-J
 
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Hope you don't get pulled over by the inspectors DOT it is illegal to have your exhaust end under the body of the vehicle or ahead of the rear tires,being in the Wack you probably won't be stuck in traffic jams and get exphiated by the exhaust.
 
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Hope you don't get pulled over by the inspectors DOT it is illegal to have your exhaust end under the body of the vehicle or ahead of the rear tires
As far as a VI in concerned, what if he ended it just before the rear axle, instead of the stock up and over?:hmm:

BTW nice common sense mode. :beer:
 

Cruisin'

Out in the shop, building something cool!
 
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Looks good! Did you re use/weld to the existing flange where it attaches to the turbo or did you buy a new one, if so where?

Thanks
I used a new flange. I bought 2 boxes at Mopac in Langley that contained 2 flanges, gaskets and hardware each. About $10. The flange bolted up to the turbo, I just had to open up the holes a little as the studs were spaced just a little bigger than the hole pattern on the flange.

-Jason
 
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