2.5, 2.75, or 3” Exhaust for new 95-97 Wit’s End Turbo? (1 Viewer)

mudgudgeon

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Builds - Reviving "the wife's" 80

Pages 5 & 6 show where I am so far.

Nice work.
I took a different approach. Mine is on the inside of the frame rail all the way. No crossing over the main frame rail.

My aim was to minimise the number of bends as much as possible. No bends greater than 45°, apart from the dump pipe, I mostly achieve this.

Pics in my turbo build thread linked in my signature.
 
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My next thing to do when I’m finally at home for a second is to unwrap and inspect the injector harness, eliminate the egr and throw the drivetrain back in. Before I start driving it I have some body parts to finish painting. The original radiator support and RHF fender were super rusted.

I have a 5:30 am flight from Fresno tomorrow to get home at a decent time in Michigan.
 
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I’m the new caretaker of LandCruiserPhils turbo 80. It has. 3” exhaust and while it is definitely not quiet, I think it sounds great. Between the turbo whistle and the exhaust growl, you might think it was a diesel. I am no expert but I can say the 3” works very well.
 
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I have to make mamas 80 stay quiet while still being able to breathe. It gives me the freedom to maybe add a couple of inches of spring height and maybe a 3-link to free up the front end someday...
 
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Cheapest and most free flowing would be cut a hole in the hood and have a 3" pipe right out the top. Install a flap so water doesn't get in. Hopefully between shifts youll see some flame. Youll also have to install a bench seat, grow a mullet, and have a chick in the middle seat while cranking some country.
Fitting a 3" pipe is pretty tight over the rear crossmember. I should have put it in a press and made it someswhat oval for mine to give a little more room for error during fabrication.
 

mudgudgeon

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Fitting a 3" pipe is pretty tight over the rear crossmember. I should have put it in a press and made it someswhat oval for mine to give a little more room for error during fabrication.

I think mine has about 3/8 clearance here. Flattening in a press a little would help a little.
Mine has no rattles, even with 3/8 clearances in several places. The braided flex pipe is key to this.
 
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Great thread, i’ve Been thinking about the same thing. I’m thinking about getting a big GM or dodge OEM muffler that’s about 2.5 and have local shop to do a cat back. Once the turbo is here then everything before the turbo will be changed too.


After some searching found that Chevy 6.2 mufflers have enormous flow so might do a 3 inch cat back with Chevy muffler.
 
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thatcabledude

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Great thread, i’ve Been thinking about the same thing. I’m thinking about getting a big GM or dodge OEM muffler that’s about 2.5 and have local shop to do a cat back. Once the turbo is here then everything before the turbo will be changed too.


After some searching found that Chevy 6.2 mufflers have enormous flow so might do a 3 inch cat back with Chevy muffler.
Not enough room unless you do the enormous muffler sideways behind the rear axle.
 

thatcabledude

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A turbo and cats won’t be very loud with just pipe the rest of the way. An 18” magnaflow that fits nicely in stock location would be sufficient I’m pretty sure.
 
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I was going to have this started recently, but due to a move back to North America sooner than expected I've put it off due to time constraints.

3.5" all the way through, the solution to go over the crossmember is 3.5" oval tubing. This measures 2 3/8" short side so easily fits with 1" clearance. If you want to do 3" equivalent that'll be 2 1/8" short side. I do expect it to be pretty loud before the turbo build... Also, the turbo I have going in will be just a tad bigger. :devil:

3.5" Burns Stainless 1-Stage Muffler
3.5" Vibrant Performance Resonator
3.5"ID/4"OD Magnaflow Cat
3.5" Burns Stainless Oval Tubing + Transitions
img_20181127_191319-jpg.1840679
 

mudgudgeon

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I was going to have this started recently, but due to a move back to North America sooner than expected I've put it off due to time constraints.

3.5" all the way through, the solution to go over the crossmember is 3.5" oval tubing. This measures 2 3/8" short side so easily fits with 1" clearance. If you want to do 3" equivalent that'll be 2 1/8" short side. I do expect it to be pretty loud before the turbo build... Also, the turbo I have going in will be just a tad bigger. :devil:

3.5" Burns Stainless 1-Stage Muffler
3.5" Vibrant Performance Resonator
3.5"ID/4"OD Magnaflow Cat
3.5" Burns Stainless Oval Tubing + Transitions
img_20181127_191319-jpg.1840679

I think you would almost be able to eliminate the 3.5" oval tube and just butt the two transitions together over the crossmember. You still need to get a flange of some sort over the crossmember during installation, or weld a join in situ under the truck

finding space for your transitions, and bends might be tricky too
 
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I think you would almost be able to eliminate the 3.5" oval tube and just butt the two transitions together over the crossmember. You still need to get a flange of some sort over the crossmember during installation, or weld a join in situ under the truck

finding space for your transitions, and bends might be tricky too

True, I considered just joining the two transitions. But picked up the extra oval tube just in case. Might have to do some pie cuts in the oval tube to do transitions and bends before and aft the crossmember. Before shouldn't be bad at all though as I'm running a much shorter resonator so ample room to play around with. Have still yet to decide on flanges. Vibrant makes oval flanges, and with some elbow grease should squeeze right through the opening at the crossmember. It's something we'll just have to figure out once it's time I guess.
 
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you guys should have a look at this video. might change your opinion on exhaust flow.

https://dai.ly/x3vupq0

Correct me if I'm wrong, maybe my theory isn't correct, but I think denting each individual header makes less difference than disrupting exhaust flow post collector. You'd need dual 4" exhaust to roughly surpass the flow of 8x 1 5/8" header. So would like to see them do a test where they disrupt flow post collector. Post collector should see faster air velocity than in each individual header tube, no?

1 5/8" = 2.76 square inches
8x 1 5/8" = 22.08 square inches
Single 4.5" = 15.9 square inches
Dual 3.5" = 19.24 square inches
Dual 4" = 25.12 square inches
 

AussieHJCruza

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Another 3" here - Safari Turbo setup. Single muffler, no cats (Oz market truck, so no factory cats, EGR etc)
I think it sounds nice, it's not quiet but certainly not annoying on highway - the turbo + the KM2s are louder on cruise.
 

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