8 Guests, 0 Users

Author Topic: Exhaust Diameter  (Read 12243 times)

0 Members and 1 Guest are viewing this topic.

Offline From_Jonah

  • Pinto Full Member
  • ***
  • Posts: 155
  • FeedBack: +0/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Fifth year Anniversary Mobile User Topic Starter Signature Poll Voter
Exhaust Diameter
« on: September 14, 2013, 11:40:03 PM »
What size exhaust does a 2.3 with a header need. It's a wagon and it will have no cat converter and I'll change the muffler to a glasspack.
1977 wagon - baby blue full restoration project.

1980 wagon - (77 front clip) converted to cruising wagon. (Sold in 2015. Canít find her again.)

RSM

  • Guest
Re: Exhaust Diameter
« Reply #1 on: September 15, 2013, 12:14:15 AM »
Usually a header comes with a reducer and those dictate pipe size. It's probably 2" What brand of header are you using?

Offline 74 PintoWagon

  • Pinto Sr. Master
  • ******
  • Posts: 3105
  • FeedBack: +540/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #2 on: September 15, 2013, 07:47:40 AM »
Too big can hurt performance, if it's just a daily driver and not a race deal I don't think I'd go bigger than 2"??, just my worthless .02...
Art
65 Falcon 2DR 200 IL6 with C4.

Offline From_Jonah

  • Pinto Full Member
  • ***
  • Posts: 155
  • FeedBack: +0/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Fifth year Anniversary Mobile User Topic Starter Signature Poll Voter
Re: Exhaust Diameter
« Reply #3 on: September 15, 2013, 04:47:04 PM »
I've not bought it yet but most likely Hedman. Seeing how it's the least expensive route. I'm wanting to build a 2.3 to more like a ministock motor but for the street so I'm wanting to squeeze as much hp as possible out of it.
1977 wagon - baby blue full restoration project.

1980 wagon - (77 front clip) converted to cruising wagon. (Sold in 2015. Canít find her again.)

Offline 74 PintoWagon

  • Pinto Sr. Master
  • ******
  • Posts: 3105
  • FeedBack: +540/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #4 on: September 15, 2013, 06:07:30 PM »
Been using Hedman for a lot of years on quite a few different vehicles and never had a problem, hard to beat them for fitment too. I wouldn't go any bigger than what the collector is though, and I'd use a good free flowing muffler.
Art
65 Falcon 2DR 200 IL6 with C4.

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #5 on: September 15, 2013, 11:27:30 PM »
FYI, when putting on headers we often cut the head flange between cylinders, it allows the individual pipes to pull up better to seal better. If you actually remove a small section then plugs easier to change as well. Pretty much stops header bolts from coming loose too. When they do header flange after welding it they commonly use a grinder to do so and like a butcher in most case. Carefully using a like 4" right angle grinder to detail the flanges to a better flat and then cutting flange like said and you can pretty much kiss gasket leaks goodbye and for the long term. After that they were as reliable as a factory manifold was leakwise.

One glasspack will probably be pretty loud. Depending on how the louvers are punched in the core, mounting muffler one way may be quieter than the other way or flipped end for end. Four cylinders are harder to keep quiet than eights, the eights have more cylinders to interfere with each other to kill noise.

Offline tbucketjack

  • Pinto Full Member
  • ***
  • Posts: 107
  • FeedBack: +0/-0
  • Gender: Male

  • Total Badges: 6
    Badges: (View All)
    Topic Starter Poll Voter Linux User Mobile User Windows User Fifth year Anniversary
Re: Exhaust Diameter
« Reply #6 on: September 16, 2013, 12:32:45 AM »
I run 2" pipe and a Cherry Bomb "Turbo" type muffler. Much better than the straight pipe I was running!!!

Offline Wittsend

  • Pinto Master
  • *****
  • Posts: 2256
  • FeedBack: +241/-0

  • Total Badges: 8
    Badges: (View All)
    Tenth year Anniversary Mobile User Topic Starter Poll Voter 1000 Posts Linux User Windows User Fifth year Anniversary
Re: Exhaust Diameter
« Reply #7 on: September 16, 2013, 10:42:41 AM »
2" sounds about right.  A lot of people think bigger is better, but that isn't so.  On the other side some people say you need back pressure and that isn't so either.  What you want is velocity. That is, you want the exhaust to move as fast as possible through the pipe.   The benefit of that is it promotes a scavenging (drawing out) of the exhaust gases from the combustion chamber.

Like all things you would ideally have multiple pipes sized for all situations. That being smaller for part throttle, normal driving and larger for full throttle power.  Sort of like an inverse, progressive two barrel carburetor. Barring doing that most exhaust are sized as an appropriate average.

Lastly turbo motors seem to like very large pipes. As best I can tell the turbo kills a lot of the velocity.  Thus, the exhaust, (now having been slowed down) needs volume (not velocity) as the most expedient way of getting the exhaust out.

Tom

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #8 on: September 16, 2013, 10:38:54 PM »
I've read a lot of Dave Vizard and from what I've seen he is probably the major proponent of high exhaust velocity. I don't necessarily buy all of that. Especially in the latter half of a system. Scavenging is much more complicated than just getting fast exhaust speeds in the pipe. For instance, get fast exhaust speed in the tailpipes and then remove them completely to where the exhaust speed drops like a rock because now at atmospheric. Yet watch the power increase by 20%. Slow down the exhaust on purpose, or even choke it up much worse like a two stroke bike exhaust expansion chamber does and watch the power go up as much as 50%. It ain't quite that simple. Exhaust power is about TIMING wave action to do what you want it too, you may need to speed up or SLOW DOWN the exhaust flow to do that. Two distinct things you are manipulating there, actual exhaust plug passage and a sonic wave that moves through pipe much faster than the exhaust plug ever could. No physical way you can EVER get the exhaust to move as fast as that wave does, so the two must be made to work together when they can.

'Necessary back pressure' is a myth, and straight from the old codgers running cars in the '20s and '30s who did not understand wave tuning. Any race vehicle I ever worked on worked increasingly better the less back pressure you have on it. Indeed the opposite is true, get system to where it can create a vacuum and power goes up like a rocket. There are ways to get that in exhaust by either speeding up or slowing down the flow.

Turbos need pipe as big as it can get to simply dump exhaust as fast as it can, you have no wave tuning with a turbo, it approaches power making from a whole 'nother angle. The waves are still there but not used for power, sometimes they even get in the way.


Offline Wittsend

  • Pinto Master
  • *****
  • Posts: 2256
  • FeedBack: +241/-0

  • Total Badges: 8
    Badges: (View All)
    Tenth year Anniversary Mobile User Topic Starter Poll Voter 1000 Posts Linux User Windows User Fifth year Anniversary
Re: Exhaust Diameter
« Reply #9 on: September 17, 2013, 01:12:36 PM »
The wave tuning is well beyond the average persons ability to measure and tune to great effect. And Flowmaster style design aside, any mufflered car likely isn't maximizing exhaust flow period.   Thus, we are pretty much left with pipe size as a variable.  Also, typically most power gain is measured in some form of high rpm racing (ET for example) or "end result" dyno run.  I doubt that a whole lot of effort goes into maximizing the 1,000-3,500 rpm cars typically operate in.  I'm not trying to be argumentative, only practical as to a daily driven car with some performance aspiration.

I'd love to see dyno tests as pure science rather than executed with a purpose. Hey, maybe this is one for Mythbusters.

An exhaust test that always rings true for me is one done on a mild Mopar 360.  The difference between stock 318 cast exhaust and the expensive 340 Hi Po manifolds was about 5 HP at 5,800 RPM. The difference between stock 318 cast exhaust and $800 TTI headers was 10 HP at the same 5,800 RPM.  Maybe in racing it counts for something, but not on the street. Note, all cast exhaust had 2" pipes 24" long.

Tom

Offline slowride

  • Pinto Sr. Member
  • ****
  • Posts: 279
  • FeedBack: +18/-0

  • Total Badges: 3
    Badges: (View All)
    Topic Starter Windows User Fifth year Anniversary
Re: Exhaust Diameter
« Reply #10 on: September 17, 2013, 05:38:24 PM »
I've not bought it yet but most likely Hedman. Seeing how it's the least expensive route. I'm wanting to build a 2.3 to more like a ministock motor but for the street so I'm wanting to squeeze as much hp as possible out of it.
Make SURE you don't use the Hedman with the slip on collector. it WILL leak, and will NOT stay sealed no matter what you do. Made that mistake.......

Offline tbucketjack

  • Pinto Full Member
  • ***
  • Posts: 107
  • FeedBack: +0/-0
  • Gender: Male

  • Total Badges: 6
    Badges: (View All)
    Topic Starter Poll Voter Linux User Mobile User Windows User Fifth year Anniversary
Re: Exhaust Diameter
« Reply #11 on: September 17, 2013, 08:02:12 PM »
Another hint: copper gaskets seal much better and don't blow out.

Offline 74 PintoWagon

  • Pinto Sr. Master
  • ******
  • Posts: 3105
  • FeedBack: +540/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #12 on: September 17, 2013, 10:46:11 PM »
Make SURE you don't use the Hedman with the slip on collector. it WILL leak, and will NOT stay sealed no matter what you do. Made that mistake.......
Slip on collectors aren't sealed they leak no matter who's header it is that's race stuff not for the street, gotta weld them up for that and even then you can't get to the back side of them, learned that myself many moons ago..
Art
65 Falcon 2DR 200 IL6 with C4.

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #13 on: September 18, 2013, 02:12:56 AM »
LOL, while I prefer flat flange collector hookups I have had a slip on ended Hooker header on my Mustang II/Pinto like forever and never any leak at all. Used them 100% of the time on bikes as well and no leak at all. On car you must have some form of resilience built into at least the first exhaust hanger/mount after the collector or engine mount flex will quickly leak the joint. I've been known to mod or add slots too for better seal.

Rule of thumb as someone just suggested, give up wave tuning if you run a full to rear wheel exhaust system. You CANNOT wave tune that. Personally, at our shop (early '70s-early '80s) we considered both Flowmaster and the at the time highly favored 'turbo' type mufflers to be crap. Back then our favorite was no tailpipe setup at all and using big core header collector mufflers alone. Short enough you could easily get some wave tune benefit out of them. In fact I took a small cubic inch AMC built to spin pretty high and had it buttoned to a latest trick 2 1/2" dual piped dual turbo muffler setup, it ran like a dog after the initial engine break-in with open headers. Ran in the high thirteens capped up at the strip or horrible. Car felt dead as a doornail, wouldn't hardly break tires loose. Came back home and immediately cut all pipe off to put on Thrush header mufflers with 2 1/2" cores using same headers. Next run after that car was busting off 12.50s same day (on regular hard rubber street tires) and no other changes, car felt like motor found another 75 HP and an honest to God powerband now. Traction became a huge problem and leaving at 2500 rpm. Motor before not wanting to go over 6000rpm was now revving cleanly to 7500. Tailpipes absolutely destroy small inch high rpm predisposed engine tuning. Bigger motors the same just a bit less depending on how radical the cam timing was.

You can only wave tune when you have your tuned length and must have zero pressure atmosphere pretty close to your figured tuned length, start adding tailpipe length and the more you do, the more that tuned effect goes away. Pipe length destroys wave tuning.

'The wave tuning is well beyond the average persons ability to measure and tune to great effect.'

Measure? Can't without some form of statistical measuring. Tune? Oh, yes you can absolutely make it better. You can wave tune lower rpm as well but that usually lowers upper rpm power and we Americans are very greedy, we want all we can get. Pretty much all your FI PCMed cars now use wave tuning in the intake manifold lengths, much of it geared toward low to mid better result, you can tell by looking at the length of the individual runners. It helps at the lower rpms found using overdrives on modern transmissions. Or better mileage. And now many actually use variable cam timing and intake runner volume changes to gain low to mid as well as ultimate top end power. Like having cake and eating it too. 

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #14 on: September 18, 2013, 02:22:45 AM »
http://www.amazon.com/Scientific-Exhaust-Systems-Engineering-Performance/dp/0837603099

You better like numbers and formulas before you tackle this one........... ..BTDT.

Totally 100% pure science there.

Also, I know nothing of the header company or other extinuating circumstances on the Mopar issue, but I CAN say that only 10 HP increase on a 360 inch motor is pretty absymal, maybe they used a single exhaust or something else to choke power. I'm used to getting a minimum of 10% and often up to 15% power increase on a stock 4 bbl. dual exhaust engine, on say 350ish cubic inch and around 300 HP, that should be at least 30 HP over stock cast iron logs there. The header design could have been pure crap, I dunno. I do know that when I see a good one I pretty much know. After looking at so many you kinda get where you know what a good one should look like. Anything coming out now referred to as 'shorty' headers are pure garbage to me. The numbers I spouted above are for a good long tube close to equal length header with normal not oversized primary pipes or can.

Offline Wittsend

  • Pinto Master
  • *****
  • Posts: 2256
  • FeedBack: +241/-0

  • Total Badges: 8
    Badges: (View All)
    Tenth year Anniversary Mobile User Topic Starter Poll Voter 1000 Posts Linux User Windows User Fifth year Anniversary
Re: Exhaust Diameter
« Reply #15 on: September 18, 2013, 04:47:34 PM »
Well, I stand slightly corrected. Compared to stock 318 cast manifolds it was 15 HP for the Pricy ($800) TTI headers and 8 HP for the also expensive ($300-$400) cast 340 manifolds.  RPM was 5,400 not 5,800.  I was going from memory when I posted.  Here is a link to the article with all the particulars (there is a dyno results chart):
http://www.moparmusclemagazine.com/techarticles/engine/mopp_0307_mopar_crate_engine_exhaust/viewall.html

But, going back to the initial post he was asking regarding the pipe size for a header and implied a full exhaust.  Myself and two others suggested 2". The rest of my post was to in general terms let him know why a 2-1/2" or 3" exhaust would have not been an asset.  Regardless, I appreciate your contribution.  It always allows me to learn and contemplate something new.

Offline 71HANTO

  • Pinto Sr. Member
  • ****
  • Posts: 507
  • FeedBack: +108/-0
  • Gender: Male
    • Older site

  • Total Badges: 6
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User Webmaster Fifth year Anniversary
Re: Exhaust Diameter
« Reply #16 on: September 18, 2013, 09:33:50 PM »
http://www.amazon.com/Scientific-Exhaust-Systems-Engineering-Performance/dp/0837603099

You better like numbers and formulas before you tackle this one........... ..BTDT.

Totally 100% pure science there.
Here are some pictures of a wave tuned header that an engineer and fellow racer hand built for my Lotus Pinto using the same book above. He was all excited to show me all the graphs and formulas but it just hurt my head too much. :o You may be able to see the primary tubes are small then they get a little bigger, then even bigger before the collector. The equal length tubes are all exactly 26.5 inches long. This maximized my power band from 4000 thru 7500 RPM. The concept is to scavenge the gases except at the exact time the cylinder is just about done filling the chamber with air/fuel. The cam overlap allows some fuel to bleed past the closing exhaust valve. The pulse backs up (or what I call echo) and stops the flow for a nanosecond keeping the fuel in the cylinder to be burned. Hence more power.
 
71HANTO
 

"Life is a series of close ones...'til the last one"...cfpjr

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #17 on: September 18, 2013, 09:38:14 PM »
Certainly not correcting you, and I go off memory a lot as well. It's just that I've done plenty of stuff chasing wave tuning and can bring other things to the table.

I used to pipe and port 2 strokes as well, probably the best way to see how striking wave tuning effect can be. It can really open your eyes sometimes.

The 2 inch will work fine, I might go to 2 1/4" in some isolated occasion.

Here's the thing. If you can fake the engine into thinking the exhaust has hit atmospheric then you approach true open conditions. One way is by putting a much bigger area around the length you would normally expect to find open end of a tuned pipe, some high-perf small engine cars can do that by adding a big area converter entry that has bocou flow in it, the exhaust thinks it has hit open air with the big cross section change. Another on dual exhausts is to add a cross over pipe (old Mopar trick that still works) between the two sides right in that area. A single exhaust to dual outlet, it doubles the area. Added benefit is the extraction the other side can add by its' plug going down pipe. What Vizard's high velocity does, the speed pulls exhaust plugs behind it along for the ride.

Nobody ever does it on cars because of space considerations (except on say formula open wheel race cars), but adding a megaphone bell can really help there. It does greatly on bikes but the extra noise there has forced almost all competition exhausts to go to canister muffler type and lost power there. Problem with the meg is you are wave tuning the exhaust AND the sound too, or the incredible loud noise they bring, proof they work.

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #18 on: September 18, 2013, 09:56:51 PM »
There you go, 71HANTO. Am I seeing that right, actually a 4-2-1 there with 1 and 4 paired together and 2 and 3 as well? That should work like gangbusters.

Noise means it's working, it gets even louder than that with a bell on the end. MUCH louder. I bet that setup sounded great.

If you use a bell there then you add a reversed short piece of bell to the end at appropiate spot and that does the end of zoop port plugging you want. The same thing as the reverse cone on a two stroke chamber. The big bell produces vacuum at the port and right at the end the reverse sends back a positive stuffing wave that stops over extraction at that point. Touchy stuff, the lengths and angles must be just right.

Basic rule. Every time a positive pressure pulse rockets down a pipe, it has a negative following it. The negative provides the extraction. When the positive pulse hits atmosphere it sends a reverse positive pulse back UP the pipe to, if timed right, provide that positive stopping plug that ends the scavenge action.

Like they say, you'll know when the exhaust is about right, pipes will go everywhere and it'll be hard to fit it into the car.

Offline dick1172762

  • Vintage Pinto Racer
  • PCCA Management Board
  • Pinto Sr. Master
  • ******
  • Posts: 2623
  • FeedBack: +362/-0
  • Gender: Male
  • I'm a llama!

  • Total Badges: 7
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts Tenth year Anniversary Fifth year Anniversary
Re: Exhaust Diameter
« Reply #19 on: September 19, 2013, 09:22:04 AM »
One thing that nobody has talked about, is that all glass pack mufflers that I have looked at, have a 2 inch core!!!! Makes no difference what size pipe is used, if the muffler used has a 2 inch core. There are mufflers that have a bigger core, but they are not stocked by your local parts store. Lobak makes both street and race mufflers with a core that match the pipe size. And they cost very little more than a cherry bomb. Stick with a 2 inch system. Plenty big for any street driven Pinto. And if you want a cheap header, just go to your local junk yard and get one off a 2.3L Ranger pick up. Very nice and made from stainless steel. It will out live the car. Get the down pipe too, to make a do it at home job easy. For a real nice sounding system, put a short glass pack under the car, and one at the tail end of the tail pipe at the rear bumper. NO RICER FART CANS PLEASE!!!!
Its better to be a has-been, than a never was.

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #20 on: September 19, 2013, 09:53:27 PM »
The way the louvers are punched into the inside core makes a big difference too, I've seen some 2 inch that were necked down smaller simply by all the louvers hanging out in space there. Also, some louver construction means the muffler will provide different noise output as well as power depending on how it is installed end for end. If done right the muffler will be seen as pretty much a straight piece of pipe. At our shop back in the day we always steered clear of any muffler that changed the direction of flow, when you turn the flow you lose there. Why we didn't use Flowmaster as well as others. Anytime you u-turn flow you will lose power I don't care who or what big name makes it. The problem? Flow will go around turns if the pipe is round, pressure waves then pretty much don't see the turn unless it is really bizarre. But when you start turning flow in a place that has oddball shapes and flats like the inside of a classic muffler case, well, round pressure waves don't like that at all. Of course, that's why muffler is shaped like that, to destroy the wave, or what carries most of the noise.

Offline 74 PintoWagon

  • Pinto Sr. Master
  • ******
  • Posts: 3105
  • FeedBack: +540/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #21 on: September 20, 2013, 08:15:56 AM »
Hmmm strange, if chamber mufflers are so bad wonder how I gained power and mileage in my dually???..
Art
65 Falcon 2DR 200 IL6 with C4.

Offline Pintosopher

  • 33yrs SCCA, 19yrs Egroups/PCCA ,40yrs enlightenment
  • PCCA Charter Member
  • Pinto Master
  • *
  • Posts: 1993
  • FeedBack: +383/-1
  • Gender: Male
  • Essses my Nirvana , Liberty to play, my mission

  • Total Badges: 8
    Badges: (View All)
    Topic Starter Signature Poll Voter 1000 Posts Windows User Tenth year Anniversary Fifth year Anniversary Photographer
Re: Exhaust Diameter
« Reply #22 on: September 20, 2013, 03:00:43 PM »
Of course, If sound levels weren't  an issue, an open ended cone  of proper size would really wake up that exhaust flow.  :o
Yes, it is possible to study and become a master of Pintosophy.. Not a religion , nothing less than a life quest for non conformity and rational thought. What Horse did you ride in on?

Check my Pinto Poems out...

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #23 on: September 20, 2013, 08:26:51 PM »
Never said you couldn't gain power with 'chambered' mufflers, you just won't get as much. Look at the race mufflers, you won't see one not straight through.

Once wave tuning is tossed out the window then the improvements come by reduction of impedance to flow only. Or, reduction of possible back pressure. ANY back pressure is bad for engine output if not intended for some certain effect.

Two totally different things although they can heavily overlap. Once pipe gets long you start looking to just improve flow with no waves involved. The waves pretty much destroyed anyway, the classic exhaust system is set up to do so. Waves=noise=bad.

If properly designed you can MAKE MORE power with a straight through muffler, you can only RECOVER some lost with a reverse flow muffler. That in relation to an engine with a stated amount of output before either one used.

Offline 74 PintoWagon

  • Pinto Sr. Master
  • ******
  • Posts: 3105
  • FeedBack: +540/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #24 on: September 21, 2013, 11:31:10 AM »
Well, anytime you put something in the flow it's a restriction that's a no brainer, but you're also talking about extracting all the power you can get out of a motor, in that case why use mufflers(unless required by a class)just use a collector. But the street is another world altogether, I've only done 2 vehicles with chamber mufflers, a dually and my current C-10 short bed, both had headers and crappy glasspacks when I got them, I put 3 chamber mufflers and crossover on the dually and it was night and day, with a self contained 11 1/2' camper and towing the race boat mileage increased 1 1/2mpg on the average and the hills were almost cut in half, of course it's not just a matter of bolting on an exhaust system and go the tune up changes as well, the whole package has to come together to get the full potential and there was some trial and error in the process. The other day I discovered a crack in the exhaust manifold on the pinto,(not leaking yet)so I'll be looking for a "good" header and I'll be putting on a chamber muffler on it, be interesting to see what I can squeeze for mileage out of the 2.3.
Art
65 Falcon 2DR 200 IL6 with C4.

Offline From_Jonah

  • Pinto Full Member
  • ***
  • Posts: 155
  • FeedBack: +0/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Fifth year Anniversary Mobile User Topic Starter Signature Poll Voter
Re: Exhaust Diameter
« Reply #25 on: September 21, 2013, 03:18:58 PM »
Well that's a lot of good info! haha. I was planning on probably using the Headman header. As far as noise goes, I have a Dynomax Super "turbo" muffler on there now. Just to keep it quiet for now. I don't really like the sound of it. I did drive a Pinto a while back with a cherry bomb at the very end of the exhaust and I thought it sounded pretty good and surprisingly wasn't very loud. I also haven't decided where I wanna exit the exhaust though. I'm kind of thinking about bringing it out in front of the passenger side rear tire.
1977 wagon - baby blue full restoration project.

1980 wagon - (77 front clip) converted to cruising wagon. (Sold in 2015. Canít find her again.)

Offline 74 PintoWagon

  • Pinto Sr. Master
  • ******
  • Posts: 3105
  • FeedBack: +540/-0
  • Gender: Male
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #26 on: September 21, 2013, 06:06:47 PM »
I was thinking of a Ranger header?, but if go with a full header Hedman is what I'll use for sure, 2" all the way and exit in the stock location behind the passenger side tire.
Art
65 Falcon 2DR 200 IL6 with C4.

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #27 on: September 22, 2013, 03:42:09 AM »
Four cylinders commonly can call for two mufflers, they are very hard to keep quiet. Harder than V-8.

Offline 71HANTO

  • Pinto Sr. Member
  • ****
  • Posts: 507
  • FeedBack: +108/-0
  • Gender: Male
    • Older site

  • Total Badges: 6
    Badges: (View All)
    Topic Starter Signature Poll Voter Windows User Webmaster Fifth year Anniversary
Re: Exhaust Diameter
« Reply #28 on: September 22, 2013, 08:50:32 AM »
There you go, 71HANTO. Am I seeing that right, actually a 4-2-1 there with 1 and 4 paired together and 2 and 3 as well? That should work like gangbusters.
Sorry it took so long to respond. Been working hard on both my Pintos. Yes, it is 4-2-1. The guy who built it also took into account the firing order. You may be able to see his grease pencil numbers in one of the pictures.
 
71HANTO
"Life is a series of close ones...'til the last one"...cfpjr

Offline amc49

  • PCCA VIP
  • Pinto Master
  • ***
  • Posts: 1256
  • FeedBack: +242/-1
  • Another Pinto Driver

  • Total Badges: 4
    Badges: (View All)
    Topic Starter Poll Voter Windows User 1000 Posts
Re: Exhaust Diameter
« Reply #29 on: September 23, 2013, 12:35:20 AM »
Yeah, the good firing sequence there, 1-4, and 2-3, 180 degree pattern....... ......I never liked the 1-2 and 3-4 that street bikes use. You can tell the difference instantly when motor is cranked up, and some extra power there too, the scavenge is even instead of lopsided.

They used several headers like that on some of the Kawasakis used in the original Mad Max movie, you can hear the rasp of 180 firing clearly there as them bad boys rip over the flatlands there.