True dual's??? thats right!

04TitanXECC · 03-12-2005, 09:42 AM

Just picked up my titan CC after i had true duals put on. the guy i went to has his own shop, and is a hard worker, and appresiated the worth of a dollar. here's how it went.

first he cut the factory Y pipe just before the intersection and ran two individual 2 1/4" pipes off of that back to the rear keeping a similar plumbing location to the factory. then had two glass packs put in 2 1/4" dia. pretty much in the same location as the factory oval. then ran a split rear exit straight out the back with 3 1/2" chrome oval tips and no H or x pipe(that isn't necessary, but would quiet it down a lot(don't want that).

with all of that said, i don't have a digital cam, but im going to try and get one from a friend and post pics as soon as i get a chance.

i have had a gibson extreme on the titan, ran straight collector for a while...LOUD...had a 5.9L ram with gibson, flowmaster, borla, magnaflow, and probably a few others that i cant think of. this is by far the best system ive had yet...ever. the sound is deep and authoritive, and the drone is a little bit louder than stock and gibson, but its not too much because its far enough back where it exits. its loud on the outside, but not so much on the inside windows up or down while driving. when i drove into my appartment complex after i had it installed there were heads turning left and right.

i know what everyone iss thinking...glasspacks!! thats gotta be loud. and the reality is that its not bad at all aspects of driving. i can still talk on the cellphone when driving at 65(loudest drone) and its no where even close to being too loud to be overpowering. i would recoment everyone to atleast hear it, if not go and get it put on. oh...and by the way, power is much better than gibson and even better than that over stock(no surprise there). and with it all welded, installed, tips and all was only $290 total. this is an awesome sounding system and for the money you cant go wrong.

the best part about the whole thing is that if i want something less all i have to do is cut out the glasspacks and weld in a dual in dual out flowmaster 50 series and its done, same length in mufflers and he set the spacing between the duals so this could be done if i wanted. take my work or come and see it...this is one bad a$$ exhaust!

TOK · 03-12-2005, 12:22 PM

I thought I read in the past that a crossover pipe decreased the kind of noise that you normally don't want... popping when you get off the throttle. It also increases scavenging and makes more power than straight unconnected duals.

I also got to hear a Titan with dual glasspacks, and it was also quieter than I expected. Sounded really nice.

04TitanXECC · 03-12-2005, 12:27 PM

the poping when you let off the gas is based off of where your mufflers are in relation to the head's. from my experience and what ive been told by experienced exhaust guys, a cross pipe is supposed to be used to equalize pressure and it only works when the tubes after the intersection are equal as well. i dont have one and i love it...not much if any cracking and good solid sound all the way through acceleration and when i let off the gas.

blachow · 03-12-2005, 12:59 PM

I had a Z that had a "true dual" and it wasn't as great as I though.

Remember that unless there is some back flow pressure you really wont be producing any extra HP's unless you stand on it and basically redline it everytime.

The Z was ok - b/c when a race would go down you were running it to red every shift. On our truck though may not be the ideal situation. I'd be surprised that in a couple of weeks you don't notice one of your exhaust exits producing a black soot and the other not so much. Power scavenging and lack of evenflow that a X or H pipe brings will be the culprit.

But hey, strap that dog to a dyno and lets see what it can do!!

--bml

04TitanXECC · 03-12-2005, 01:47 PM

theres enough backpressure just from the tube diameter(2 1/4") so there is not much if any low end torque loss

blachow · 03-12-2005, 03:09 PM

You know - that is a good point.

Anyway - I bet you saved a boat load of cash having it made by someone you know. Unlike the rest of us.

I wish I had a friend w/ a shop and that kind of know how!!

--bml

04TitanXECC · 03-12-2005, 04:29 PM

actually not...i talked to the guy on friday afternoon, discussed pros and cons of different systems and left the truck there for him. he came in at 5am this morning and had it done around 7am and i picked it up at 11am handed him $290 and that was it. never knew this guy prior to this. just a good guy that knows the value of a dollar and doesnt overcharge.

gftitan04 · 03-12-2005, 08:40 PM

Quote:

Originally Posted by 04TitanXECC

theres enough backpressure just from the tube diameter(2 1/4") so there is not much if any low end torque loss

Thats the whole reason why I shake my head when I hear people going to a larger pipe when they do their exhaust. They don't seem to understand that you will loose back pressure, which turns into power loss. You need more horse power to justify a larger pipe.

TitanHauler · 03-12-2005, 11:36 PM

Sounds like you got the exact exhaust you wanted! Awesome! Can't beat the price either. Congrats.

JohnC · 03-13-2005, 06:06 AM

Backpressure is NOT a good thing. A perfectly tuned exhaust system has NO backpressure, but actually creats a vacume. It's true that too large a pipe will drop horse power, but this is because exhaust scavenging is reduced in too large a pipe. A well tuned set of pipes will actually creat enough scavenging to creat a vacume, not back pressure.

Sorry, but people saying an exhaust needs backpressure bugs me. With all the good info available these days I find it hard to believe the backpressure myth persists.

04TitanXECC · 03-13-2005, 06:44 AM

not as if im an expert or anything, but can you explain how you can create a lower pressure in the exhaust as to create a vaccum without an external pump or something to decrease the pressure? and how is it that this is optimal versus having the perfect tube diameter/volume to remove the exhaust with minimal to no resistance?

JohnC · 03-13-2005, 08:26 AM

I'll try to summarize, from what I've read various places.

How scavenging works, or vacuum is generated. It's really just momentum of the exhaust gasses that causes this effect. After combustion, a very high-pressure exhaust pulse exits the head, and proceeds down the header/exhaust-system. By the end of the exhaust stroke the momentum of the gas will actually pull exhaust from the head, leaving negative pressure in the head. This is ideal. This is also why there is overlap in exhaust/intake valves. While this vacuum is being generated, fuel&air start entering the chamber, even before the intake stroke actually starts doing its thing.

The diameter of the pipe controls the speed of this gas pulse. If the pipe is too big there isn't enough momentum to do any scavenging. If it's too small there is too much backpressure for the gasses to even get out of the way, let alone scavenge.

Of course calculating the correct diameter, header length,... is based on Cubic inches of displacement, and tuned for certain RPMs. That's why Bigger diameters generate higher horsepower, but hinder lower RPM torque. There is an optimal speed for the exhaust to travel through the exhaust, to generate the most scavenging. It's tricky stuff(beyond me) getting it right for a specific application, and there's always tradeoffs(Low-end torque or high-end HP).

Backpressure is never your friend. Backpressure means for that give RPMs your pipe is too small. That's probably why people say you need backpressure or your loose your low-end torque. I guess it's kinda accurate, but it seems to me most people are misunderstanding the actual issue.

Some newer motorcycles have some cool flapper things that change the diameter of the exhaust at different RPMs, helping to increase lower end torque, yet free up the exhaust path for higher end HP.

Hope this helps a little. And, please any experts chime in and correct any inaccuracies.

Tim Sloper · 03-13-2005, 08:41 AM

Backpressure is bad. Changing from the stock exhaust (post-cats) to a cat-back system is never going to hurt the performance assuming the new cat-back is not increasing backpressure from where it was. The area where you will need to pay attention is if/when long tube headers become available or you are going to be looking into camshaft swaps. At that point you need to become more selective and make sure your proposed setup is going to support the power/RPM range of interest. If you are shooting for maximum power output in the upper RPM ranges you wouldn't want 1 5/8" headers. You would want 1 3/4" headers. The 1 5/8" would just be too restrictive at the upper RPMs.

These 2 links sum up the backpressure issue pretty well...

http://www.automotiveforums.com/vbulletin/t13199.html

http://www.uucmotorwerks.com/html_pr...torquemyth.htm

Tim

**gr8titan** · 03-13-2005, 10:47 AM

Quote:

Originally Posted by Tim Sloper

These 2 links sum up the backpressure issue pretty well...

http://www.automotiveforums.com/vbulletin/t13199.html

http://www.uucmotorwerks.com/html_pr...torquemyth.htm

Tim

Thank you for the above links. It's just great to witness intelligent and well supported discussions of any topic.

I just had a custom exhaust installed and the fabricator/installer, www.mufflex-performance.com said the same things about exhaust principles.

The attached thumbnails is my system & what they call the "scavenging muffler"

hvyjnkr · 03-13-2005, 02:25 PM

Quote:

Originally Posted by gr8titan

Thank you for the above links. It's just great to witness intelligent and well supported discussions of any topic.

I just had a custom exhaust installed and the fabricator/installer, www.mufflex-performance.com said the same things about exhaust principles.

The attached thumbnails is my system & what they call the "scavenging muffler"

gr8titan
That is a nice looking exh.! If you don't mind me asking, how much did you pay for it??? And what kind of mufflers and tipd did you use?

Chris