All Small Six Effective 170 Exhaust System-What Should It Be?

[GreasyNRusty]

Question: Current thought--What should the exhaust system look like? ("Aluminized or stainless steel color look" is not a good answer).


I'm getting to a point where I need to start planning the total exhaust system.
Street use, hopefully everyday-use, 170 4-dr. '63; torque-oriented; some head-work, 9-1 CR, RV-cam, nuthin' fancy. Headers and free-flow exhaust a must.

I'd prefer dual exhausts, underneath the bumper at the rear...just because they look cool. But I'm not totally wedded to that idea; this (ahem) 2.8L needs all the help it can get...if a single-outlet exhaust works better, so be it.

I am definitely going with tube headers, l-o-n-g tube headers: Should they be 6-into-1 single-exhaust or 3-in-into-1 x 2 dual exhaust?

Not doing 3-1 straight duals; from prior experience--way, way too loud with unpleasant overtones, but since that car (30 years ago) woke up neighbors and cops alike, "H" pipes, then "X" pipes have been developed.

Duals with"H" pipe or "X" pipe? Or just single? Pipe diameters in either case? And no, I am NOT retrofitting a converter.

What type and brand muffler(s)?s? Turbos? Glass packs? (I rilly, rilly don't want this thing to sound like a Civic).

Suggestions?

Eddie

 

[bmbm40]

Good info here:

B

All Small Six Thread 'exhaust sounds good is a v8 though, how would six sound?'

Dec 25, 2024

Post #16 exhaust sounds good-it is a v8 though.

Opinions on Single exhaust for v8

I’ve been running dual exhaust on EBs for over 25 years . I love the sound of duals but I have been fighting fuel vapor lock for many years . I was thinking of going with a 2 into 1 to a magnaflow muffler. I have a mild build 289 and in process putting on a AX-15 . I like the fact that it will...

classicbroncos.com

• bmbm40
• Replies: 23
• Forum: 144-250 "Small Block" Six Performance

 

[Frank]

Question: Current thought--What should the exhaust system look like? ("Aluminized or stainless steel color look" is not a good answer).


I'm getting to a point where I need to start planning the total exhaust system.
Street use, hopefully everyday-use, 170 4-dr. '63; torque-oriented; some head-work, 9-1 CR, RV-cam, nuthin' fancy. Headers and free-flow exhaust a must.

I'd prefer dual exhausts, underneath the bumper at the rear...just because they look cool. But I'm not totally wedded to that idea; this (ahem) 2.8L needs all the help it can get...if a single-outlet exhaust works better, so be it.

I am definitely going with tube headers, l-o-n-g tube headers: Should they be 6-into-1 single-exhaust or 3-in-into-1 x 2 dual exhaust?

Not doing 3-1 straight duals; from prior experience--way, way too loud with unpleasant overtones, but since that car (30 years ago) woke up neighbors and cops alike, "H" pipes, then "X" pipes have been developed.

Duals with"H" pipe or "X" pipe? Or just single? Pipe diameters in either case? And no, I am NOT retrofitting a converter.

What type and brand muffler(s)?s? Turbos? Glass packs? (I rilly, rilly don't want this thing to sound like a Civic).

Suggestions?

Eddie

Dynomax super turbo mufflers sound great. Not loud, but noticeable. Never raspy, no drone. My favorite on a big6. They flow plenty, made in USA by Walker.
For max power at least use a X pipe or a Y pipe into a single. Torque is lost with dual exhausts.

 

[aussie7mains]

Performance wise, there isnt much to note here, anything low restriction will work, I find a big single works best in most cases, and is tonnes easier to fit. So use your headers, long or short, it matters little, then run a single pipe with turbo type muffler in no smaller than 50mm. Duals will work when the six has 6 separate exhaust ports, the 170 doesnt, so mothing to gain here. Look for inspiration on BMW sixes, they have simple fabricated manifolds with 2 outlets, they give plenty of power.

 

[awasson]

I tend to agree with @aussie7mains. In my mustang with the 200, I may opt for duals at some point just for looks but at the moment I chose to go with a 6 into 2 header and then put a Y pipe at the colllectors and the single all the way back to a turbo type muffler, then up and over the axle and a turn down just at the bumper. The collectors are 2-14” so I went with 2-1/4” throughout. It’s pretty loud. If it were my daily driver I might put a resonator before the muffler.

EDIT: It’s unlikely to ever sounds like a Honda Civic, especially with a header and low restriction exhaust.

 

[aussie7mains]

I tend to agree with @aussie7mains. In my mustang with the 200, I may opt for duals at some point just for looks but at the moment I chose to go with a 6 into 2 header and then put a Y pipe at the colllectors and the single all the way back to a turbo type muffler, then up and over the axle and a turn down just at the bumper. The collectors are 2-14” so I went with 2-1/4” throughout. It’s pretty loud. If it were my daily driver I might put a resonator before the muffler.

EDIT: It’s unlikely to ever sounds like a Honda Civic, especially with a header and low restriction exhaust.

Resonator probably better right down the back, easier to fit there too. Dont use reversed glasspacks (we call em hot dogs) pretty useless as a muffler, OK as resonator.

 

[powerband]

(Port Divider will effectively make the small six one port per cyl'... )
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...'built' motor will most always sound different (better?). Most small six's will develop dreaded drone at certain RPM/Road speed. Big bore mufflers and typical glaspaks' seem to aggravate the low drone.
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works for me:
Two OEM - stock mufflers on the 'Pursuit 170' '63 for no drone, quiet cruise and @ 1/2 the backpressure as a single out.
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'built' 250 in '61 uses two "Smithy" mufflers to show some attitude and not overwhelm at cruise with NO DRONE.
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both use Hooker long tube duals', use of flex fittings encouraged .
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have fun
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[GreasyNRusty]

And:

He finally replies...(hopefully nobody has been holding their breath waiting for the event)

Good help and ideas; Thank You(s)(?) one and all; I missed on the '63, which is OK-ish 'cause what I rilly want is a '66/'70 2-door Falcon.

I'm still up in the air whether it's to be dual exhaust or single, for all the pro-and-con reasons and pics listed above.

I would like to contribute one link to a REAL COOL dual-outlet header/X-Pipe to true dual piece that Vintage Inlines has catalogued:
https://www.vintageinlines.com/product-page/copy-of-starter-kit-dual-exhaust-stainless

That piece would definitely bring the exhaust system up to current thot plus make a dual-outlet/dual system way easier to fab. VI also provides it in mild steel, which would be my choice.

Eddie

 

[awasson]

Just to muddy the waters a little bit more, earlier this week, I had the local Midas Muffler guys update my exhaust and as far as the fit finish and tone is concerned, I’m really happy with it. It’s back with them at the moment because the pipe that goes over the axle was too close to the axle and hits at full suspension travel but that’s besides the point; they are replacing that section on warranty of course.

I have my Mustang 200 L6 attached to an EBay Header 6 into 2, followed by a Y-pipe to a resonator and then into a Walker one inlet to two outlets. It’s 2-1/4” from the collectors to the rear. I think the tips a 2-1/2” or 3”. It used to be quite loud but it sounded cool. Now it still sounds cool but not as loud. The muffler I used is the one for the 5L (305) Camaro. I think it’s a Walker 18375 Steel Direct Fit Muffler.

Normal operating temp idle around 500-600 RPM
View media item 313
Cold start and high idle (from about 1200 at start up to about 2,000 RPM as it gets to speed)
View media item 317

 

[ActionYobbo]

I am running the larger cast iron manifold with a port splitter on 3&4. The pipe is 1-7/8 to a muffler with 1 in and 2 out then 2 pipes to the rear at 1-1/2. So far it’s doing the job and it’s quiet.
I ran the largest stock cast iron manifolds on my budget build drag car for 2 years before I got some tuned length headers for it. Made exactly no difference. Ran the same on the quarter and the dyno looked almost the same with a 3hp increase at mid range. That was 1990 since then I just use the cast irons on builds.

 

[DON]

I’m no exhaust expert, but no one has addressed the question of what to make it out of. I have a stainless system from Magnaflow, and I love it! It’s not shiny but it’s not rusty either, I used the stainless band clamps, nothing is welded, removal is easy, I did polish the outlets. And if you do want to clean a section, remove and WITH RUBBER GLOVES, use muratic acid for swimming pools CAREFULLY!! Watch out for fumes! Rinse throughly It cleans up nice. It’s been 10 plus years and looks good .