TTI Exhaust

[directconnection340]

I have purchased TTI headers for my 72 340 Duster. Im looking at the 3" exhaust that came with it. Im considering ordering the 2.5 version of the exhaust because the 3' seem too big. Any suggestions from anyone?

 

[RustyRatRod]

There's no such thing as too big. Just ask a woman.

 

[TF360]

I think 2.5 is perfect, and it may fit better. Unless you have a serious race car

 

[directconnection340]

Thanks I thought so!

 

[rumblefish360]

I have purchased TTI headers for my 72 340 Duster. Im looking at the 3" exhaust that came with it. Im considering ordering the 2.5 version of the exhaust because the 3' seem too big. Any suggestions from anyone?

A lot depends on power output.
An open 2-1/2 pipe or one with a glass pack type of muffler (straight through) will handle 600hp.

If you’re not making above 600hp+, the 2-1-2 will do right. Fit easier, weigh less.
From here, the muffler choice is the only power limiting item in the exhaust.

 

[AJ/FormS]

You already own the 3".
Race cars run open headers; is that too big?

I installed the 3" on my 367, in 1999, and I've never been sorry.

 

[Darter6]

I think 2.5 is perfect, and it may fit better. Unless you have a serious race car

It's all in what you like. 2.5 for all my stuff.

An open 2-1/2 pipe or one with a glass pack type of muffler (straight through) will handle 600hp.

Agree. But others may feel different. My 472 Indy Hemi Belvedere ran 2 1/2 with DynoMax Turbo mufflers. Not a problem. BUT it was a street car only.
Yes, I'm sure it gave up horsepower but was quiet until the loud pedal hit the floor.

 

[George Jets]

TTI 2.5" >

☆☆☆☆☆

 

[directconnection340]

Thankyou

 

[4mulas]

3" is pretty big. Not a lot of clearance between the gas tank and rhs leaf spring. 2.5" was/is tight there. I recommend 2.5"

 

[RustyRatRod]

I have the TTI 2.5" single exhaust on the slant 6 in Vixen. It made a big difference. If I had a V8 in it, I'd gone with 3".

 

[rumblefish360]

It's all in what you like. 2.5 for all my stuff.

Agree. But others may feel different. My 472 Indy Hemi Belvedere ran 2 1/2 with DynoMax Turbo mufflers. Not a problem. BUT it was a street car only.
Yes, I'm sure it gave up horsepower but was quiet until the loud pedal hit the floor.

LOL, I’m sure you did though max hp and loud isn’t always needed. There is a lot to be said for ear drums not hurting and being able to hear while driving and well after driving.

This is my thought process on my current ride, the ‘79 Magnum. While you can hear a bit of a rumble at WOT, at cruise, conversation is easy to do. It’s a driver and a go anywhere driver at anytime.

The 5.9 in it has mild mods so it feels good under acceleration and still gets respectable mileage w/3.55’s.

 

[BrianT]

I have purchased TTI headers for my 72 340 Duster. Im looking at the 3" exhaust that came with it. Im considering ordering the 2.5 version of the exhaust because the 3' seem too big. Any suggestions from anyone?

You already have the 3" exhaust? If you decide to go with the 2 1/2" exhaust I might be interested in the 3". Can you post a pic of the tail pipes? Thanks!

 

[CFD244]

LOL, I’m sure you did though max hp and loud isn’t always needed. There is a lot to be said for ear drums not hurting and being able to hear while driving and well after driving.

This is my thought process on my current ride, the ‘79 Magnum. While you can hear a bit of a rumble at WOT, at cruise, conversation is easy to do. It’s a driver and a go anywhere driver at anytime.

The 5.9 in it has mild mods so it feels good under acceleration and still gets respectable mileage w/3.55’s.

What mufflers are you running? Any drone?

 

[340sFastback]

I run 2 1/2 TTI pipes with Dynomax Ultraflo straight through mufflers. Zero back pressure in mufflers. No drone and with overdrive trans hums along at highway speeds just a mellow rumble is all you hear.

 

[ir3333]

If you are under 400 hp the stock 2 1/4" exhaust is fine and leaves lots of wiggle room.
...but you didn't want to hear that.

 

[340sFastback]

If you are under 400 hp the stock 2 1/4" exhaust is fine and leaves lots of wiggle room.
...but you didn't want to hear that.

The stock 340 head pipe on driver's side is 2 inches off the manifold with a giant pinch to clear torsion bar at least thats how original pipe was. Then you have original chrome tips that are around 1 5/8 inner diameter choking flow. The original 2 1/4 system choked them down. A true 2 1/4 system no pinches or chokes anywhere on stock cammed 340 yeah would be fine....

 

[ir3333]

I think the original drivers' side down pipe may have been 1 3/4" and probably won't make a difference on the street?

 

[Robzilla]

I have the 2.5" kit on my Swinger and Demon. Fits nicely.

 

[RustyRatRod]

I have purchased TTI headers for my 72 340 Duster. Im looking at the 3" exhaust that came with it. Im considering ordering the 2.5 version of the exhaust because the 3' seem too big. Any suggestions from anyone?

Ain't no way in hades I'd swap out a 3" system I already had for a 2.5" system. I'm a huge proponent of leaving the exhaust the same diameter as "whatever" the header collector is. I don't care what the argument is or who makes it. A restriction is a restriction and going to a smaller pipe RIGHT off the header is a big restriction. I know. Here come the bullcrap arguments about "increased velocity" out of the warped imaginations of people who've probably never even made a dyno pull. AJ is usually so fulla crap his eyes are brown, but post #6 got it right.

 

[directconnection340]

You already have the 3" exhaust? If you decide to go with the 2 1/2" exhaust I might be interested in the 3". Can you post a pic of the tail pipes? Thanks!

 

[RustyRatRod]

And hey yall, he's got TTI HEADERS why ON EARTH are yall talkin about manifold down pipes and torsion bar pinch pipes? Just to increase your post count? To try to sound intelligent? He'll benefit 100% from a 3" exhaust right off his HEADERS. Down size to a 2.5" system? Ridiculous.

 

[directconnection340]

if you look at both pics the whole exhaust is there. Over the axle 1 piece and h pipe mid section also tips and all hardware except mufflers

 

[RustyRatRod]

I run 2 1/2 TTI pipes with Dynomax Ultraflo straight through mufflers. Zero back pressure in mufflers. No drone and with overdrive trans hums along at highway speeds just a mellow rumble is all you hear.

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I'm not being a smartass, I'm just asking. Have you actually MEASURED back pressure?

 

[ir3333]

Rusty, Did you get up on the wrong side of the bed? Lots of enthusiasts read these posts...manifold down pipe info may benefit another member. The poster will gain nothing but weight with the 3" exhaust. There, i said it!