Ok exhaust gurus .. I recently read a thread about how dual exhaust and our sir cooled motors dont mix ... well I need some serious help ... I have 74 2.0 with dual exhaust that I have come to learn may be bad .. I have a set up with twin flow master mufflers, one on each side ... Is this bad ? I also have an ANAS system brand new that I can put on the car. Should I expect a performance improvement ? man I cant type the wine is getting to me ... help a brother out .. should I replace my current system with the ansa or leave it alone ? I have a stainless set of headers that I can couple up with the ANSA muffler ... keep in mind this my wife's car .... will it be too loud ? ... Wsould I pass out I'll check back in the am ... Helpppp .....

Aww .. come on I know your out there !

I thought you had more experience than "most of us combined".

The fact that you'd even consider the dual muffler arrangement without any scavenge characteristics tells me all I need to know....

OOOps.

Lets try this....


Yea dude...!!!!! Do it.. it will make huge Horse Power and you will love it. And with 2 flow masters it will NOT be loud at all....

Bitchin... Please send pics when you are done... Your wife will love you for it.

C

You'll need a hitch to tow a gas pump behind you.... and a gas mask for tuning the engine.... Take a few sets of spark plugs as well cause she'll be fouln' em like hell!

He did say 2 cylinder. That might have been Briggs & Stratton.

awlright .. your just bein mean ... If'n you want to build the absolute meanest harley I can help .. but ... these flat fours are alien too me ... how do I say I'm sorry .. I suck .. help me out .... What I can say is that my typical two cylinder will most defintely have an expansion chamber ... my "lo-tech" motor will make 100 squared at 1550 cc ... which is pretty low compared to Jake ... but pretty good for us back yard guys .... I appologize if I offended you guys .. I've been in the two cylinder game for 15 years and build some killer motors but I'm not sure it transfers to the 4 cylinder game .... sorry if I offended .... I will more then likely need your help in the future .... So please accept my humble "i"m screwed appology" .....

No problem... This engine has as much in common with a Harley as it does a Chevy....

No worries.

Gas pump in town ... no crap ... we're not lookin for mileage here ....

Ok ... so back on topic ... should I scrap the "dual" exhaust ? wait .. I think you all helped me answered my own question ... duh ! Ok but will I see an improvment in how it runs ? cause it runs pretty darn good right now ... i'm not sure how it could be improved ??

Dual exhaust destroys the scavenge of the engine mostly due to the firing order of the TIV.

If you want to lose 20-30+ HP go ahead and run duals... You'll always think something is wrong with the carbs because they'll always run rich- thats just the lack of efficiency biting you in the sass..

You NEED to listen to our two part 4th dimension radio show on exhaust design and implementation onto various engines..

No collector= no power.

Let me be clear .. this "set-up" came from you west coast folks ... I didnt touch it since it got off the truck ... your brothers got some splain'in to do Lucy!

uh, Jake isn't west coast



Georgia.....

Lots of fools on the West coast too...

Bursch exhaust with SSI HE's works really well or CFR Header get you 5-10hp!

I noticed your radio show but havent had time to listen to it yet ... You can bet its on my top of the list to listen to .... i will most definitely "ditch" the duals and go for the collector I have sitting in the garage ..

4 into 2 into 1 is best. 2nd best is 4 into 1, 3rd best stock heat exchangers into common collector into high flow muff. or some thing like triad. then stock type
exhaust. then duals or open heat exchangers.

any one agree

these are based on general principles

based on Dyno Results not seatofthepants!

Geez ... I'll just shut up now ... talk about put foot in mouth ... help I cant stop ... man oh man ... gotta be the "soda" ... forgive me ... I'm not to sure where "air cooled heaven" is ... see I'm a stones throw from "road america" so its all foreign to me ... hell I'm polish to boot ...

Awright ... I've got a set of SSE's and an ANSA muffler for the car... so what your saying is I need to upgrade ? ... damn ... I had plans for that money

Listen to my Radio shows and you'll know that I am not from the left coast.... Aircooled heaven is 20 acres on top of a mountain in North Georgia. It's a land where watercooled vehicles are prohibited from entering and it's the mecca for Type 4 development.

hey doper if'n yur build'n hoggs you otta know that a equal length 2 in to 1 with the right size pipe for diameter and length primaries [the two part of the 2 into 1] and the right diameter and length on the collector [the 1 part of the 2 into 1] tuned for the displacement and rpm range of the engine will make best power than 2 straight pipes ever will.


right?

just agree and we'll never know the difference.

that stuff will be ok, not the best but ok.

not as loud as the flowmasters

Awright folks ... see you in the am ... its officially 12:00 am ... and the wife aint too happy gotta go .... thanks for the help ... and the work .... geez and I was gonna sleep in tomorrow ...

Doper,

Read this.

Dual exhaust thread. Dated Yesterday



Clayton

Ok .. one last reply .. Mesix .. your right duals on a harley rob power beyond what the "loud" guy next door thinks .... I switched from a really nice "shot gun" style system to a dual system and lost the whole "top end" like 20 hp ... Duh ... long story .. dont ask something to do with a bet but I knew better... but If you want help with a twin I can get some pretty "interesting" components ... some day I might confess how ... but not tonight ...

Clayton,

thats the one that got me asking questions about what I have ....

Doper

I run SSHE's and a Anza (Not sure if that is the same as a"ANSA muffler ") muffler,

I have been happy with the performance and the sound.

I have built many M/C engines for MotoX as well as sand drags, (2 cycle) and

we do use chambers, but I have never heard of putting a chamber on a 4 cycle.

I wrenched for Bills M/C in Glendora, CA. building mild to wild. Never put a

expansion chamber on any of the 4 cycle engines. I am not saying that you

haven't, I am just saying that you might want to try running a different style

of pipe I will guarantee you they will run worlds better.

Thats exactly what I'm going to do ... me thinks the POS was a bigger idiot then I and thats tough

Google a Harley "Thunder Header". Looks a bunch like an expansion chamber.

And they work GUD...!!!!!

C

hey doper , do you have any furniture on your front porch?


i mean 80 cars? how many on cinder blocks?

It does kinda look like a chamber but it would not work like one. I have seen

them on drag bikes.

yep ... my good buddy ... developed a killer system for 2.0 twin ... oops ... midwest ... go figure ... what do I know ... nothing ! or maybe a little who knows how many millions are at our disposal.... I use my friends ! .. if you cant screw your friends who can you ? .... no dont take that literally ! I value my buds more then they will ever know .. but I know more then I should ... after all I'm "just" a chassis guy ...

naw thats not it. it's just to add volume to the muffler. i cuts the noise and allows the exhaust gas to cool b4 it exits the exhaust.

expansion chambers need to be right off the exhuast port to "pull"the exhuast gas as it expands out of the combustion chamber on a 2 cycle engine. you need an expansion chamber for each cylinder to be effective.

Sh$t ... I recently was part of a "cylinder" contest ... the one with the most cylinders wins ... crap .... I won ... No .. I've ad 80 .... but thru support of those like yourself I'm down to 5 toy cars and 5 dailies ... geez ... that sounds bad ... honey which one do you want today .... whatever .... she always takes the buick ..

I built an H-1 for this big fella, those three chrome chambers coming back by the

swing arm was a thing of beauty...Scary Fast.

Yep .. but its a tuned length to effective .... you just cant throw a pipe and muffler at it ... they work in sinc ... as you folk should know ...

the buick huh? that must be the one that starts up every time.

Damn ..I was done an hour ago .. you guys gonna help me smooth crap over with the ole lady?

An expansion chamber does not have to be right off the exhaust port, it's tuned for the combination (damn i sound like Jake now). An expansion chamber should work on 4 cylinder motors too, just not as effectively as the damned exhaust valve gets in the way. Can still get the exhaust pulses to create more of a vacume in the cylinder.

The packaging problems will be huge. And i agree there needs to be one per cyl for it to work properly (can do it after the collector if primaries are short enough, but it's even harder to build and tune).

BJH

yah i was just refering ti the muffler part that looks like a expansion chamber. that is just a muffler volume thats is a low restriction design. has nothing to due with 2cycle type chambers.

[quote name='messix' date='Apr 13 2007, 10:48 PM' post='888362']
[quote name='doper' post='888359' date='Apr 13 2007, 11:44 PM']
Sh$t ... I recently was part of a "cylinder" contest ... the one with the most cylinders wins ... crap .... I won ... No .. I've ad 80 .... but thru support of those like yourself I'm down to 5 toy cars and 5 dailies ... geez ... that sounds bad ... honey which one do you want today .... whatever .... she always takes the buick ..
[/quote]
the buick huh? that must be the one that starts up every time.

Still under warrenty so I dont care

wow i didn't think honda,yamaha and suzuki would be so far off with there race bike technology, what with all the road bikes and dirt bike championchips. you would think with all the four strokers out now that they would have htat on them too if it made power.

IMO Yoshimura is the holly grail of ricer exhaust and they do not make a chamber

for a 4 cycle engine.

Jake,

I get to mid-alabama on regular basis ... I'd love to cruise up to your place when the wheels touch down on hotlanta ... can we get together or is it a tough deal?

let me know .. oh by the way dinners my treat ....

thanks ....

doper

Like This??



BJH

Yep .. this is serious too us americans . And I dont work for polaris ....

doper yer gonna be in big trouble with the wif! better go kick the dog outta his house but thank him for warming it up for you!

Too .. late ... she just hollered at me bout' the stereo being too loud and something about the kids ... call me toast ... see you folks in the am

The high pressure gas exiting the cylinder initially flows in the form of a "wavefront" as all disturbances in fluids do. The exhaust gas pushes its way into the pipe which is already occupied by gas from previous cycles, pushing that gas ahead and causing a wave front. Once the gas flow itself stops, the wave continues on by passing the energy to the next gas down stream and so on to the end of the pipe. If this wave encounters any change in cross section or temperature it will reflect a portion of its strength in the opposite direction to its travel. For example a high pressure wave encountering an increase in area will reflect back a low pressure wave in the opposite direction. A high pressure wave encountering a decrease in area will reflect back a high pressure wave in the opposite direction. An expansion chamber makes use of this phenomenon by varying its diameter (cross section) and length to cause these reflections to arrive back at the cylinder at the desired times in the cycle.

Click to view attachment

Sorry but that is not a expansion chamber like we used on a 2 cycle. Weard looking though, leave it to FMF.