Origional 40 series flowmaster muffler and a glasspack on a 97 XLT?

[TyHarris]

im not tryn to get into it with ya man but that 4.0 i was talkin about was mine. maybe your right, you learn somethin every day and i sure as hell dont know everything. HOWEVER, when i reved MY engine on the dyno over 3000 rpms it sputters and dies. then we put "dyno pipes on" about 1.5 to 2' long cone shaped steel pipes designed to imitate the pressures of a full sized exhaust system. then it easily reved over 3000 rpms. maybe its just mine, maybe im onto somethin but if it works for me then im gonna do it. id rather keep riden with maybe a little to much back pressure than possibly stallin out after i hit 3000rpms.

[hunterdan]

The term backpressure is used in the wrong sense. What you want is exhaust velocity. Smaller pipes keep the velocity high which help with scavenging. The smaller the pipes, the less surface area to cool the exhaust gases. When the exhaust gases cool too much, you create turbulence and slow the exhaust flow down. That is where the term backpressure gets loosely thrown in there. The goal is to find the pipe size that will maintain good exhaust velocity at low rpms, but not inhibit power at higher rpms. Just dumping the exhaust out the manifold will do nothing for power, it would actually kill it. You need some length of pipe for scavenging. What many racers do is the crayon test. They draw a line down the pipe, where it stops melting is where they cut it and turn it out the side. Or they go to the next smaller pipe if they want it to exit in a certain area. Try driving a truck or car with a clogged cat. Tons of backpressure, and absolutely no power. Trust me, you don't want backpressure. And adding a cherry bomb glasspack in front of a fm 40 will make the exhaust quieter. There is more surface area to absorb sound. That is why a lot of guys run Dynomax bullets in addition to other mufflers. To get rid of drone. Oh, I've had tons of different exhaust setups on my explorer, including straight pipes, glasspack and fm 40. My favorite was the cherry bomb pro. Look it up on YouTube.

Dan

[TyHarris]

ok. between the cherrybomb extreme and the flowmaster origional 40, what would sound better in a 4.0 V6 OHV? i like the loud low growl.

[FIND]

Some kind of flowthrough muffler into a glasspack would give you that without having the tinny sound that Flowmasters always seem to have on V6 engines or stuff like that.

[hunterdan]

Cherry bomb extreme would be louder. Not sure how it would sound on the ohv.

[TyHarris]

how long should you run the engine before you take the crayon to it? and i know they sound ok, not quite deep enough but could be fixed with a big tip, on the 99 rangers. and those are smaller blocks than the one in my ex.

[hunterdan]

Not sure since I've never tried it, but I'm assuming you draw the line down the pipe while the engine is cold, then run the motor. Take it for a trip on the highway for a few miles running the engine like you normally would. The point at which it stops melting is where you need to dump the exhaust or start over with smaller pipes

[TyHarris]

took a red crayon to my exhaust pipe up near Stoval/Oxford, NC last night, drove back to raleigh and checked my line. everything in front of the muffler was white, everything behind was red, so since to legally pas my inspection in wake county (muffler required), ima chop the muffler off, replace it with a glasspack then bolt a tip directly to the glasspack (bolted due to the fact that i will have to change the glasspack every once in a while). i know what tip ima use (auto zone part #35217) but what glasspack do yall recomend? ive always loved the sound i get from cherrybombs on the larger displacement engines ive had, but i dont know how the cherrybomb baffles would sound on a 4.0. what are yalls prefered glasspacks and why?

[beach]

Way way back in the day I tried multiple setups on an ohv V6 and whether Flowmaster or Magnaflow or Edelbrock etc, all sound like sh!t. Ohv V6 just does not sound good, plenty of 6 cylinders sound good, just not that one lol. Go with what you want, but it just won't be aggressive at all or low or deep sounding, more like raspy and wheezy lol, don't be one of those people that thinks loud = aggressiveness. I also had headers on it as well.

Reminds me of back then too when I sold it and bought an 5.0 Ex and modded it, yet a buddy with his Ranger 4.0 ohv and Flowmaster 40's for whatever reason thought his truck sounded as nice and aggressive as mine..... when it sounded more like a bucket of nails in a can lol.

[hunterdan]

Originally Posted by TyHarris

took a red crayon to my exhaust pipe up near Stoval/Oxford, NC last night, drove back to raleigh and checked my line. everything in front of the muffler was white, everything behind was red, so since to legally pas my inspection in wake county (muffler required), ima chop the muffler off, replace it with a glasspack then bolt a tip directly to the glasspack (bolted due to the fact that i will have to change the glasspack every once in a while). i know what tip ima use (auto zone part #35217) but what glasspack do yall recomend? ive always loved the sound i get from cherrybombs on the larger displacement engines ive had, but i dont know how the cherrybomb baffles would sound on a 4.0. what are yalls prefered glasspacks and why?

Basically what you found is that your current muffler is the biggest restriction in your exhaust. Switching to a higher flow muffler should cause the crayon to melt or discolor. I would keep the tailpipe because in the end it will sound better. But I have to disagree and say that with the right muffler the ohv sounds decent. But obnoxiously loud and they sound bad.

[FIND]

Originally Posted by hunterdan

Basically what you found is that your current muffler is the biggest restriction in your exhaust.

Well, that and the fact that his muffler has about many times the surface area to dissipate heat, therefore his exhaust charge is much cooler afterwards.

[TyHarris]

chopped the muffler off and took off everything behind it. put on a 2"in.x3"dia.x25" glasspack strait-piped from the CAT then tomorrow im gonna put on a few inch flex pipe to get around my rear axle then put on an 18" magnaflow 3"dia. high performance tip. that should make a lower deeper aggressive growl. not to loud but not to quiet either. my exhaust system will only just barely reach my back axle. ill have 38 inches of fiberglass in a 2 and 3 inch diameter... i was also thinking about another way to give it a unique sound. what if after the glasspack i made out of 2" pipe, a 180 degree turn, run a pipe back up the side of the glasspack, roll the pipe back around the start of the glasspack turn the pipe again so the exhaust is again moving towards the rear of the truck then put on the tip on. so that way it will be kind of like a bugle configuration. it'll save space, use the underside of the truck as a resonator, and might make it a little more choppy and aggressive. what do yall think?