Mufflers or straight pipe ? Do you think you would get better gas milaege with mufflers or just straight pipe. Any ideas?
From my experience, it depends on a lot more than just whether there are mufflers or not. My guess is, the co$t of the tickets you'll get running straights will offset any per-gallon $aving$, if any.
Using gl*** packs or any type of restrictive muffler would hypothetically cut fuel mileage on a vintage (non computer controlled) engine if it restricted flow ie horsepower unless you use a scavenging type muffler or exhaust systm that helps increase flow. Of co**** with alot of these the sound is far from traditional. Its hard to beat the sound of gl*** packs, with just around 2" type pipes all the way out the back for that traditional cackle sound.
Motorcycle baffles wrapped in 'gl*** mat and stuffed in the side exhaust makes this flathead sound great!
what engine? Low compresson engines sound ok with straight pipes...but anything over 7 to 1 its just loud, also no back pressure hurts horse powder on an engine thats tuned for some. The cam overlap allows air/fuel to go straight out the exhaust valve when theres no back pressure....if you want that straight pipe sound , some where in the system add in a smaller tube to restrict it just a little.
I have straight pipes on my coupe. Its so load my wife can hear me get off the highway a mile away no joke. Will have to figure out mufflers soon. Good luck
I run straight pipes with 12" self-made baffles on a bone-stock 283 in my '62. The pipes exit out the back with bellflower tips. It is a little loud, but not too bad unless I really step on it. It's a daily driver and I've never been pulled over.
To the question; I doubt if you will be able to tell the difference in gas mileage. I have never heard anybody remark that running straight pipes had any effect on gas mileage. I would only guess that you might see a very minimal improvement, but I doubt if there is anybody that has ever actually tested the theory. Of course with systems engineered to the goal of improving gas mileage were developed and tested, the cost would offset any gains one way or the other. Personally I never cared. I keep the tank full, just burn gas for the fun of it. I run the 'pipes for the loud, with removable baffles put back in to quiet it when I want too. When I need more quiet, I stuff a little steel wool in the baffles
Fill up your tires, make sure the alignment is perfect, remove any unnecessary weight, change the gearing to a lower number to slow the engine speed for a given vehicle speed. Were you serious about MPG? I doubt that you would see a difference if you have duals. Just the difference in how you drove it to hear to open pipes rap or feather it past cops would change the MPG more.
Ok hear goes I think the wind was a factor and the weight was to. I usually run 2 1/2 pipe out bak with motorcycle mufflers on the end which brings it down to 1 7/8. I have straight pipe out the back now 2 1/2 all the way I have a fuel injected 4.6 ford motor and I was getting 26 mpg now with the straight pipe I averaged 20 to 22 mpg from nyc to chicago it was really windy and I did averaged 85 to 90 mph. Which probably shortened the mpg to. I was wondering what the majority vote was on straight pipes and muffler loud is cool and so far no tickets Thanks for the input see ya at the hunnert
"Slight" backpressure is better for low end torque. Tailpipes all the way out the back will provide this, mufflers or not. Especially with a few bends around the transmission/frame and up and over the rearend. I had straight 2-inch pipes all the way out the back with pencil tips on my 60 El Camino. Basically stock SBC, it was a 307 with powerpack heads. It would be a bit loud at full throttle, and would be just fine at normal throttle levels. Never had any tickets or even comments about the noise level. I do not think there is any benefot to straight pipes as far as mpg vs a good flowing muffler. You do it for sound. I would not run straight pipes any more, maybe I am getting too old, but I like a deeper tone mufflers give better than the sharper rap sound of straight pipes.
Well, actually .... no, it's not cool worth a damn. It's just irritating. Why do so many people confuse quality of sound with quan***y of sound?
I built my own mufflers , what I did was take a 18" gl*** pack and cut it in half so I had two 9" mufflers , then I cut around the outside shell and pulled the core out with the fibergl*** still around it. Slide that up into your header and weld a tab to hold it , then I made a slight turn out just to get the exhaust fumes away from my door. Been that way for 3 years and sounds nice and deep.
My O/T daily I ran with a jury-rigged exhaust for a long time (the muffler shop wanted about twice what I paid for the truck to replace it) and the gl*** pack muffler fell off a couple times. It got better milage with it on than with it off. Also, it was annoying to drive with it off, so bad one of the times I fixed it on my back in the parking lot with a new piece of pipe before I drove 100 miles home. Having a Y-pipe, cat and one muffler doesn't seem to make much difference over the replacement truck with duals, turbo mufflers and no cat. But I think that's a loaded question and it's going to vary with the engine type and size, carburated or computer controlled fuel delivery, and the weight/size of the vehicle.
Heres my model a with zooomes just got it running a few weeks ago. Strted on it last june did all the work. But had it wired 1st car ive ever donehttp://vids.myspace.com/index.cfm?fuseaction=vids.channel&friendID=475957357
Quote:[Well, actually .... no, it's not cool worth a damn. It's just irritating. Why do so many people confuse quality of sound with quan***y of sound?] I agree, perhaps if you remember the sound of a well built engine at idle, high lift cam, good compression, timing advanced, headers pinging, and MUFFLED, you'll appreciate the trouble the owner went to, to make the beast streetable.
Hmmmm... Interesting topic. I have a situation where I'll be running lakes-style pipes with cut-outs and I'll run pipes out the back. Problem I have is there is very little room and couldn't have a muffler longer than say 10-inches. I'm just looking to suppress the sound as much as possible for long road trips. I'll probably run it uncorked around town. Anyone running small circle-track style mufflers or something similar, just to cut down on the DB's??
As a muffler man for 32 years I can say most builders don't leave the muffler guy anywhere to hang a muffler. X's in the frame , flat floors all get it the way. That muffler Flowmaster makes the hushpower, it fits in a small area and does a good job of handeling sound BUT, you can't run a very long pipe behind it or it sounds like a gl*** pack.
Intresting.... Just me and everybody likes something different but I had those hushpower II on an OT K-5 blazer and could not stand them ! Was louder than no mufflers but with a 2-1/4 full tailpipe. (Read long pipe behind it) The sound was so bad, sounded like **** at idle just awful, not pleasent at all, the droan was like nails on a chaulk board, and they were so much money for mufflers, that i took them off, took them back and put in a couple chunks of straight pipe till I could find some that fit. The straight pipes were much more quiet inside the truck than the hushpower, still loud but you could at least hear the radio. http://www.truckcustomizers.com/products/flowmaster-hushpower-ii.html
Loud pipes make you deaf before your time, ask *anybody* that's been around cars a while. Your ears do not toughen up or get used to loud noise, they simply lose capacity to hear. Then there's tinnitus(permanent ringing in the ears), another thing *many* rodders have and you do NOT want. Just my public service message. You may now return to your regular programming
Go with the mufflers. Straight pipes on the street is just one more argument for noise ordinances, manditory vehicle inspections, smog laws and other government B.S. regulations nobody needs. Plus, people who aren't into cars appreciate loud exhaust noise like the rest of us like 110 decibels of hip hop from the "dub" mobile sitting next to us in a traffic jam. Plus, driving a car with an open exhaust gets really old, really fast.
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