what are you running for exhaust?

[IDIoit]

today i installed a new exhast system on my 87 project.
cut the flange to the turbo down to about 2".
replaced the 2.75" down pipe with some 3".
3" collector flange out to 4" pipe.
8 feet of straight 4" dumping out right before the rear wheel.
good gawd she sounds great!
esp. when i down shift to 2nd
even spooked a teenager in the back of a prius....
what are you guys running?

 

[chris142]

the 2 inch pipes off the manifold go into a "y" that goes to 3 inch pipe all the way back.i have a 3 inch flowmaster. i often wonder if duals would have been a better choice. or possibly a 4 inch pipe instead.

 

[IDIoit]

my buddy also has 4" on his non turbo IDI, damn near sounds like my FE390, without the RPMS.
if its not turbo'd, id say 3" duals all the way.
but then again, i love a throaty exhaust.

 

[Dieselcrawler]

3 inch DP up to 4 inch under the passenger seat. then diamondeye 4 inch dual output kit for a 95-97 stroker.

 

[PwrSmoke]

the 2 inch pipes off the manifold go into a "y" that goes to 3 inch pipe all the way back.i have a 3 inch flowmaster. i often wonder if duals would have been a better choice. or possibly a 4 inch pipe instead.

That's a pretty optimal setup for a NA 7.3, Chris. Big single pipes produce better power than duals unless the duals use an X-pipe or crossover to connect the two banks. Bigger isn't better with exhausts. It's a "Three Bears" thing that can all be calculated out. Which I did in a post some years ago here. Of course, so many don't want to believe any of that because "bigger is better." Once you reach the point where the system is big enough, going bigger is a waste of money, won't deliver any more power and, if too big, can actually COST power... as least at the low rpm part of the curve.

The weak link for a single system is where the front pipes connect. Optimally, the two front pipes are of nearly equal length (as long as possible) and meet at a nice-flowing Y. Three inch pipe flows more than enough for an NA 7.3 as long as the muffler isn't an impediment... and a Flowmaster won't be. Don't get exhaust envy, Chris!

 

[KZF250]

3" no muffler and dumps behind passenger rear wheel. Sometimes when driving in traffic I just turn the radio off and listen to the exhaust...Simple things in life bring the most pleasure. Also impressed at how quite it is a freeway speeds.

 

[A48WillyzGuy]

Mine is what I'm assuming to be the stock pipe back to around where the front fuel filler is. From there, I put a 4" Magnaflow muffler attatched to a Dynomax tailpipe made for a 99-03 Super Duty. I've got a 45 deg bend in the mail that should put the exit right behind the rear tire. Then I'll slip on my MBRP 4"x5" tip.

It currently sounds like a mild 460. I wanted quiet and a performance gain. This setup dropped my egt's around 150 deg across the rpm band from the stock exhaust/deleted muffler that came with the truck... and was obnoxiously loud. It also made a big increase in low end power.

 

[FORDF250HDXLT]

i dunno how you guys can stand that.i tried with a short straight through muffler first and that was way too much.running empty was ok but when you hit the hills at 12-16k gross it got so old real fast.
then i went to turbo and then walkers big truck muffler setup on both trucks now.a bit too much whistle on chip truck with the windows down but nothing i can't stand and no more screaming demon noise under load up the hills when they downshift.

 

[sjwelds]

ATS full 3" dp to 3.5" pipe off an OBS powerstroke. muffler replaced w walker 21470. Dumped straight down right before the axle. I think it sounds great.

 

[chris142]

the reason i questioned the 3inch with a flowmaster is that it did not make any power difference. i was very confident that just losing the stock tailpipe with those screens in it would be a huge improvement.i did not notice any difference using my butt dyno and timing myself to the same telephone pole every morning

 

[icanfixall]

I have a length of 4 inch without a muffler. Only bend is to reach up over the rear axle and dump out behind the passenger wheel. I found out the Banks sidewinder down pipe is not 3 inch but 2 7/8 inch so I had that inlarged to 3 inch. Then the piece of 4 inch straight pipe was reduced to meet that 3 inch. What joins the 2 pieces is a band clamp. Now its simple to remove the down pipe. No more trouble with the u bolt pipe clamps that crush the pipes. Its really surprising how much noise is reduced by the turbo too. Untill I really start working the engine. Then it speaks up telling me its working hard pulling.

 

[theguruat12]

Whatever came standard y-pipe with the original Banks turbo, then the downpipe that came with the kit, then 3" to a standard turbo muffler, then 3" all the way out to stock location. I didn't install it, original owner did. Sounds decent when I really gun it. Eventually going to replace with maybe 4" from end of downpipe back, with a different muffler, mostly because the turbo muffler is so damn big.

 

[blacksmoke94]

3" ATS dp, 4" Diamond Eye straight pipe and 5" Diamond Eye tip dumping out behind the rear wheel. Can hear the turbo really well and going down a hill at 70 and turning the overdrive off it sounds like an exhaust brake. It's loud but I like it. I couldn't believe how much the muffler actually dampened the noise. The kit came with an 8" flow through, 4" in/out. I did actually notice a power gain by removing the **** and going to the straight pipe.

 

[ToughOldFord]

Factory piping after the down pipe, glasspack instead of the stock restrictive muffler. No, it's not loud.

 

[Black dawg]

when truck was NA, started out with a big glasspack rest of exhaust stock. sounded good no real power gain.
Next was built a good y pipe and 3 inch back to the glass pack, and used stock tail pipe. This made very noticeable power improvement, and sounded good, but very mellow

Ended up keeping that exhaust after I added the turbo, and it seemed to work just fine.
Next I cut the down pipe as short as possible and ran 4 inch straight tubing, no muffler, and pre bent 4 inch tail.
Was a decent step up in power, but the real gain was over 100 deg egt less when working it really hard.
One of these days it will get a muffler again.