Pacemaker Triflow into dual exhuast

[Anonymous]

The headers on my 2V have been gradually blowing out over the last 12 months and I have just replaced them with some pacemakers fitted to a dual exhaust. The guy who did the fitment is a specialist in Castlehill and I came upon him after taking some advice from Addo and another guy who lives close by re don't just go to any exhaust fitment place.

I am stunned by the difference a great twin system makes over my old high flow single system. I drive the car now simply to hear it run.

The guy who fitted it used to work for a Ford dealer many years ago and really knows his stuff.

I didn't set out to make it sound like a V8 but I swear you couldn't pick it unless you really put your mind to it.

If any locals want to know who the fitter was, it was Dave at Castlehill exhausts.

Mark

 

[addo]

I saw Mark's car again today - just by coincidence driving by where I was walking - and yes, the exhaust note is deeper than I would have expected.

 

[Anonymous]

What have you got Mark is it 2 and 1/4 inch? One muffler on each pipe or two? straight through mufflers? I want mine alot quieter but still deep.

 

[Anonymous]

Sorry Tim, have been a bit slack on the site over the past week.

They're two inch pipes into a two (I think this is right) triway mufflers which then finish as two inch pipes out the back.

Dave the exhaust guru explained that it is the mufflers that give the system the necessary backpressure. The exhuast comes in at the front of the muffler returns from the rear back to the front via a U bend and out the rear via another U bend. You tech heads out there are probably laughing at this inadequate description!

Anyway the engine feels like it has more torque over the old single straight through system which I think may have been a 2 1/2 inch system.

Mark

 

[xctasy]

We know what you mean Mark. You are onto it man!

The smaller 2" pipes aid scavenging. Most people miss-construe this to mean an engine has to have a certain amount of backpressure to work on the street. Actually, this isn't the case, but we know what you mean.

Dick Johnston decribed the critical air speed and exhast drainage speed in a Street Machine article in the 80's. No-one has listened to him yet.

What is the case is that two smaller pipes will be cheaper, sound better, and will give a much better midrange power without hurting the peak power much because the gas speed will extract each slug of exhast gas better. Open it up to a single 3", and it will loose a lot of midrange torque, and then come up trumps only at the power peak.


It's very hard to build a low restriction exhast with a small diameter pipe, but if the bends are 2.5" over the axle and where the bends are big, an the actual cfm rating at 25" Hg is above 300 cfm in each muffler, then it will work as good as no restriction does in the mid range.


The partially dual exhast systems of the early XR6, and certainly the very low restriction EL GT exhasts had twin pipes from the cat, then went to dual mufflers, and only ran a single tail pipe becasue of the nasty Watts Linkage got in the way.

The best option for a leaf sprung six is to copy wsaIII's dual out header, then run a co-joined X-pipe, then go to dual outlets with dual mufflers.

That will make it sound brialliant. And save the cash like Mark has, and stay away from huge dual pipes.

Jag E-Types, Aston Martin DB's and Maseratis GT 3500 ran dual out exhasts of a fairly small diameter, and sounded great. Especially the last DB6 and DBS 4.0 Litres. That's why Tickford XR6's had the special exhast. If they could have, they would have run dual outlets.

Ford boys have to reclaim the musical notes.

If you have one, send me a tape, and I'll put your XY's exhast note on the web, Mark.

 

[Anonymous]

Hey Xtaxi, I would if I could. I've lost my graphics after it took me a year to get them on to the site in the first place. I am a total techno moron.
I don't know how guys like you and addo figure out all the internet stuff.
Mark.
Ps one Q, what does the X cross over do on an exhaust?

 

[xctasy]

From wsa111's post

http://fordsix.com/forum/viewtopic.php?p=156435&highlight=#156435

 

[Anonymous]

Thanks XTaxi. I do remember reading this. Mark

 

[Anonymous]

I am also needing to build an exhaust system soon. The comments above are some great ideas and are right on time for me. See if I have this right.

I also have been looking at running 2" pipes but the bends concerened me. Such a simple solution, probably common knowledge at every pipe shop in the country but I didn't think about it. Thanks for the tips Xtaxi.

OK, so I run 2" pipes off of the header, through two mufflers(I have no cats) then over the axle with the 2.5" pipes and anywhere else there's a large bend, then out the back using 2" pipe. Sounds simple enough. Should yeild good scavenging while providing enough flow capacity.

Does the equalization pipe help much on a straight six? Also, while an X pipe looks like it should flow better than a pipe welded perpendicular, does the X equalize the pressure as well?

What's the muffler of choice? Which performs the best? Sound? How about the Super Traps?

One more thought, If I wanted a sigle pipe out the back, do they make a two in and one out muffler that doesn't adversly effect the flow? The reason I ask is because my gas tank is offset to the left. It looks like it might be pretty tight trying to run duals.

 

[xctasy]

X pipes
The X-pipe is just

1)a means of tuning the noise out and ensuring the car doesn't rumble.

2) A means of equalising pressure pulses without creating standing waves which snarl-up the gas flow. The work hydraulic enginers do with flow equalisation is directly applcable to a fluid in its gas state.

3) What the X-pipe avoids is the most common six cylinder mess up. The moment you group a big pipe a lower tone and you get a deaper rumble which drones at the 1200 to 2000 rpm mark, right when you use it.. In Aussie, the Holden Commodore boys with even fire GM 3800's always mess up the exhast by shoving in a big single, and then it rumbles and drones, and sounds like a Model A, or worse, a VTEC with a 3" phart can. Same with after market XR6 normally aspirated exhasts. XR6 Turbo kits wit big singles seam to quiet things down, but they still sound bad

The balance pipe allows the slugs of exhast gas to move on out quicker. Each leg of the dual out header has a higher velocity when they are X'd via a small cut.

NASCAR and AVESCO, and now the latest aftermarket Holden kits go right to an X pipe, and it makes them sound nice. V8's benifit more than sixes, but Aussie sixe cylinder owners always have been told to go for a big single, and I've never heard it produce a nice exhast note yet.

Dual Rear Mufflers
Consenus from the Americans are that the best dual mufflers are the Borla's and then the Flowmaster 40, and to a lessor extent, the louder Flowmaster 50 and 60's.

The key is finding a near stock muffler that flows 300 cfm at 25" H20 pressure on each side, and then make it out of common V8 pipe. Even two stock V8 pipes is better than a big single for sound, cost, and ease of fitting.

Back end Issues
Ford XE-AU's had nasty Watts Linkages which made grouping the pipes mandatory. All post 71 US Fords tended to run nasty cross flow mufflers or were gas tank restricted by the crash bumpers and safety aspects.


Items which work.
The first EB XR6's I've seen came with was
a single shorty header exhast to a single cat,
to a dual muffler system under the back seat floor pan kick,
and then joined back to a big single.

Everything after that was just crap.

The aftermarket sells what fits and is cost effective, not what makes power and good mellow noise.

My best advice is to follow the OfenokeeComets set up. Way in the distance, you can see the two dual out pipes look like they siamese, but don't.

http://fordsix.com/forum/viewtopic.php?p=135404&highlight=#135404

In my opinion, copy his set-up, and weld the x pipe together just 4" along from the cross member humb.

This would allow you Aussie guys to run an X pipe like Wsa111's with a little less pipe, and a smidgen less effort.

Heres one with an H pipe

http://fordsix.com/forum/viewtopic.php?p=146840&highlight=#146840


Whatever, do something different!

 

[Anonymous]

Just listened to 63DropTop's audio clip and it sounds close to mine.

I like the rumble and I don't find the increased tone coming out of the pipes annoying when I rev it. I could sit all day and just listen to it idle and pip it on the accelorator. I had a single system on it before and it sounded awful.

 

[Anonymous]

This has lots of info on best muffler. Better still, for all of article go to Google type in "Giant muffler comparison" as it will give more of artice this way than in link below. Has sound clips as well.

http://autospeed.drive.com.au/cms/A_038 ... larArticle

xtaxi
Why so large over the diff axel 2 1/2 and perhps only 2 inches? for the rest. Are two 2 1/4 exhaust too big for a 250 six?
Does it make any difference to the sound have two exhaust exiting close to each other (do you still get the twin system note) at the back or are they better seperated at opposite sides?
I have a 2 1/2 single and its is deep at idle but im not sure if I like sound under acceleration and its loud.
Its no good accelerating fast away from the lights if everyone thinks your engines going to "blow up" at only 3000 rpm due to its undue noise. Also because of the noise the guy next to you in his stock Commodore probably thinks youve reved it into the stratosfear to get it to go quicker than his when in fact you may only be doing half of the RPM he is doing (make that a quarter of his rpm).
Subdued, deep and distinct is much better?