exhaust!

[rileyrs]

so i finished my exhasut on the 02 ranger, and let me just say, it came out great!

it made the sohc sound as v8ish as ive ever heard a ranger or explorer sound. it almost sounds similiar to a diesel up a high rpms. it can be a little loud at times, but i like it.

so anyway, what im runnin is, i removed both downstream cats by unbolting them at the plate where the two pipes y together.
then i ran two straight pipes out, and y'd them together into 2.25, ran that back, and turned it and dumped it out the side, b4 passenger tire.

so right now i still have the two upstream cats, and thats it, no muffler, and it is surprisingly quiet for having no muffler. but the y and pipe that runs under the cab really quiet it down.
i might add a small muffler like a super 44, or a cherry bomb extreme, but for now, im gonna leave it.

anyway thought id just say that, if you live somewhere that you can remove the downstream cats, or drive offroad only, you can make your sohc sound very, non-ricey.

i can post pics and sound clips later if ppl want

 

[CHEESYPOOFS]

on a V6 personally i like a flowmaster 50 delta flow. Good and loud but clean, not too raspy like a 40 series would be being so free flowing.

 

[Sams01XplrSprt]

can u post pics and get sound clip too

 

[rileyrs]

here are the two pics i have, sorry they kinds suck, it was with my cellphone.

tomorow i will get good pics of the whole setup, and i will get some clips too.

i tried a flowmaster 40 series on there, and a trush turbo, and they were both way to quiet, i thought.
i think ill stick with no muffler for now,
i have a set of jba headers ready to go in, so once i get those in, if it gets louder, i might try out some more mufflers.

 

[CHEESYPOOFS]

theres always cherrybomb glasspack

 

[rileyrs]

i tried a glasspack too, and it did so little, that i didnt think it was worth a $50 price tag.

 

[CHEESYPOOFS]

hmmm well the thing is anything like magnaflow or a flowmaster 40 or 44 is gonna be way too freeflowing for a v6

 

[rileyrs]

there shouldnt be any such thing as too free flowing, any muffler will be less free flowing that the current straight pipe.

 

[CHEESYPOOFS]

well i know ur looking for something that will work with ur V6 but even the flowmaster 40s will not be a ton better. You need something with a lil back pressure.

 

[rileyrs]

im sorry but thats simply incorrect, no car ever needs backpressure, not even the sohc, despite what people say.
backpressure is always bad.
what is good, is a condition that creates backpressure which is the higher pressure within the exhaust, than the atmospheric pressure. also know as the exhaust pulses, which pull the gas out, but this simultaniously creates back pressure, so many people confuse these.
also gas velocity is needed, and smaller pipes yield higher velocity, often people use too large of diameter pipes, and their gas velocity is now so slow, that is also kills the exhaust pulses, and they loose power, and it leads them to falsely believe that they need backpressure.
but if your system is done well these pulses will work together to pull themselves out, so the engine doesnt have to, which keeps gases flowing quickly. and my headers will help do that.

i know this is a commonly confused issue, but its just not true that a free flowing system is bad.
many people just think the sohc needs backpressure because they put a flowmaster in their stock system and it loses power, but thats simply because they didnt do the rest of the exhaust, and the cats are destroying that exhaust pulse, and making the engine work to expell the gases from the combustion chamber.
but if the whole system is done right, then there is no back pressure, but good solid pulses... and in turn More Power!!!

anyway, hopefully that explained backpressure, its kinda hard to explain, but ive read tons of stuff on exhaust theory, and this is the best way i can explain it, since its kinda hard to put in writing.


btw, ill try to get some sounds clips of the ranger up sometime soon, and hopefully some full system pics, and pics of the headers soon to go in.

 

[CHEESYPOOFS]

LOL man im sorry but i know about 20 people on this site alone that will argue with you. I have a 5.0 and that engine particularly needs atleast some back pressure. Without it you lose throttle response.

 

[hunterdan]

I agree with the OP, backpressure is a bad term and is used widely. Your exhaust system when set up correctly will balance everything out and be more efficient. You want your system to work to scavenge the exhaust out of the motor, and you want the exhaust velocity to be high to expel them out of the system as quickly as possible. One way to do that is with a smaller pipe. But that smaller pipe lacks the required volume you would need at a higher RPM to have any gains. Another reason why a larger pipe kills your low end is because the exhaust gases start to cool off in the bigger pipe. It acts almost like a radiator allowing more surface area for the gas to cool. As has been mentioned before on this site, 2.25" to 2.5" pipe is the optimal size for any 4.0 that is NA. Now, if you notice a loss in power, there are a few options that may help. Ceramic coating, and header wraps. On my Frontier, which is a DOHC 4.0 motor rated at 261 hp, I am running dual pipes into a flowmaster Super 40, then running dual pipes out in front of the rear tire. I am using 2.25" pipe . I also have the pipes from the cats, to the muffler wrapped in header wrap, and I also wrapped the muffler. Now, at first I had no wrap and it had more bottom end than my previous set up with a single 2.25 - 2.5" tailpipe, and a good gain in the top end. But then I wrapped the system trying to see if it would cut down on some of the noise, which it didn't but I noticed that once the motor warmed up, it seemed to pull a little harder, especially down low. The wrap was keeping the exhaust gases much warmer and keeping the velocity higher, and my system has very little if any "backpressure".

Dan

Oh, and I'd love to hear a soundclip of the ranger and the setup looks good.

 

[rileyrs]

thanks for the stuff about cooling gases dan, i forgot to mention that.

here is info about the V8 and why people believe they need backpressure.
a segment form a post on mustangforums, by Professor Wizard about H pipes:
http://mustangforums.com/forum/2005-2010-mustangs/96138-cross-over-exhaust-pipe-explained.html

Start Quote:
The firing order of all production V8s, regardless of make, has one cylinder in each bank that will fire within 90 degrees of crankshaft rotation of another cylinder in the same bank. This occurs twice during completion of the entire firing order. These two cylinders will be exhausting almost simultaneously into the same exhaust manifold system.

Full-length four-tube headers help separate these pulses until the collector is reached. If this is a full race car running "open exhaust", you will notice the collector dumps into a short open pipe at least 2.5 times the size of the header pipes, or the header pipes dump direct without a collector. This is done to avoid the conflict of pressure caused by the timing of the 2 counter firing cylinders, which will create back pressure and degrade torque, horsepower and general performance, especially at higher RPM.

On a full exhaust system, after the header tubes dump into the collectors, the two close firing cylinders are fighting each other for space in the collector and exhaust pipe. The result is reflected pressure waves traveling back up the exhaust system, backpressure, lost power and poor economy.

At the same time two cylinders exhaust in one bank, there is no activity in the opposite bank. The traditional H-pipe equalizer allows some of the excess pressure to bleed over to the 'quiet side' of the exhaust system, resulting in some low and mid-range torque improvements. At high RPMs, however, in traditional exhaust systems, the gases cannot bleed across the H-pipe fast enough to help power significantly. Performance systems with the H pipe design, attempt to over come this by using a shorter cross over pipe which is also slightly larger in diameter as the main exhaust, then would be used in a standard exhaust.

To overcome the power loss of "over loading" the H pipe design, Exhaust manufacturers came up with the X pipe design, which features a tangentially Siamese crossover junction to synchronize exhaust pulses. The X-pipe concept is to split the flow in the crossover junction, so the pressures on both banks will be equal and pulse-free after the crossover, regardless of the rpm. Volumetric efficiency and power are therefore improved at all engine speeds. The negative aspect to the X pipe design is, because of the crisscrossing of the flow stream, harmonic pulsations will develop on some systems at certain RPMs, which will be perceived as a buzzing or humming sound.
End Quote.

so the reson people lose power in their v8's is because they have a cat back exhaust, and there is now an uneven flow of gas due to the firing order having higher pressure in one bank than the other, and these gases are forced to merge into a Y-pipe and they slow down while conflicting, and then can escape the exhaust system fast enough, and the engine has to work to expell them, and there is a loss in power.
so once again, if a FULL exhaus system is done correctly, for the motor that you are workin with, then always the best option is one with little or no backpressure.
but if you only do one part of the system as a free slowing setup, and leave the rest, then you can indeed loose power.

 

[rileyrs]

btw i have seen a noticable difference in mileage based on my scan guage, which measures the amount of fuel injected, and high end pull seems to have improved alot!
i know i removed the cats, and i know thats generally not the best thing to do, even though i dont have inspections. but dont worry, i plan to install high flow cats soon, i just couldnt afford to put those in yet, so i figured id drive without em for a while just to do all my experiments and finish my exhaust system, then ill get to some high flow ones down the road.

info & sound clip:
http://www.youtube.com/watch?v=JDrD8mVWqeQ
driving clip:
http://www.youtube.com/watch?v=_ozpfJG3IsE&feature=channel
some more pics:

 

[hunterdan]

Sounds very similar to the way my OHV sounded with no muffler. Look into the cherry bomb pro muffler. It will knock the loudness down, cut some of the rasp and sound even better. I am very partial to that muffler, and am seriously thinking about going to it when/if I redo the exhaust on my Frontier. I just have to see if it would be cheaper to run 2 new pipes out the back, or just run a single 3" out the back and add a new muffler.

Dan

 

[rileyrs]

thanks man, ill deffinately look into that one. i was thinkin about the cherry bomb extreme, but i will check the pro out too. i just wanna find a muffler that wont break the bank, but i dont really want a glasspack... they just arent my favorite, but i like the way the chambered ones sound.

i actually saw ur vid of the 98 on youtube, it does sound really good, its still a nice low sound, but not super loud.
i might have to try to demo one of those muffler and see what they are like on the ranger.