Yesterday I had my muffler guy remove the Walker mufflers due to the drone and installed 30'' Smithy's and although it sounds great at idle as soon as I put my foot into it the drone is worse. I have Dynamat everywhere and a thick jute pad under the carpet but the vibration is awful, I'm thinking the tight tuck headers is where to start first...what are you guys using for exhaust and not getting any drone with an SBC?
Thanks Bob...the headers have to go and I will be picking up the Ram horns soon Sent from my iPhone using H.A.M.B.
I used 265 manifolds to clear the steering box on my 46, 2"X 26" Smittys, 3"X 12" "ECHO CANS", the thing sounds fantastic, my opinion!!
Rick...thanks! where did you place the echo cans? Do you have any pics of your set up? Sent from my iPhone using H.A.M.B.
If the mufflers aren't in the right location, you will get a drone. I have Flow Masters on my 46, the rear of the muffler is 9"-10" from the axle. No header's, old style manifolds that are below the plug wires. (Early Chevelle). The Merc has ceramic coated headers, Magna Flow's mounted the same way, no drone or rumble.
Exhaust ends just under the rear of the body, I had long tips on there before and it still droned. Here is a pic, 30” Smithy’s and when I lean back into the seat and tilt my head back it is way more tolerable. Sent from my iPhone using The H.A.M.B. mobile app
Thanks guys, I just ordered the ram horns and should have them on in a week and go from there, the drone is hardley noticable in the back seat so I'm saying the headers are 75% of the drone.
Mufflers need to be back near the rear axle, not under the seat . The closer to the motor the mufflers are , the less effective they are. And no offense ,but your exhaust guys bending and routeing ability are not really up to par. Larry
ZZ4 engine. Sanderson tight tuck hraders. 2.5" forward pipes into 3 chamber short Flowmasters and into 2.25 tailpipes turned down towards the ground inside both rear fenders. A little loud but I wouldnt change a thing. No obnoxous drone.
Yea, the exhaust was thrown together around 10 years ago and the guy I used was next to my work and probably not the best, but when I get the ram horns on there this guy I am using should be better. Just wondering why you said the exhaust doesn't look right? I need to know this stuff cause I hope this is the last time this car will be in a muffler shop for a long time! Also...a while back I was told to mount the super turbos up under the back seat and then instead of routing the tail pipes up over the axle and out...I was told to continue under the axle with an X pipe then out to the rear. Thoughts on this? thanks guys...
WTF!! X pipe, super turbos, your driving an old Ford right?? Hot Rod, Street Rod, not a HellCat or a Z06!! My exhaust follows the same path that Henry followed, between the bottom of the frame and the floor, through the oblong holes in the frame and over the rear axel, along side of the fuel tank and out the back, if you have tube shocks in the back your exhaust guy will have to make a slight bend around them but any Shop that knows what there doing will make it work! Stick with the Smittys, you'll be happy!
That is how mine is routed, through the oblong holes over the axle....looking into Helmholtz resonators if I don’t fix it with cast iron manifolds and placing the mufflers farther back. Sent from my iPhone using H.A.M.B.
Nope, the wife has not been in the car since putting the Smithy's on...but my boy gave me the look driving down the road right after the install, he said....WTF, this is supposed to be drone free? It makes your ears ring for a while after going for a 15 minute drive.
I’m following up what was done to help tame the drone. First thing I did was change out the headers for ram horns and drove it over to my exhaust guy, that was fun, no drone but loud as hell! He connected the ram horns to new pipe and added 2 ea 22” resonators out back with tail pipes 2” past the bumper and it is so much better. The tone is still present but not that head cracking drone that was there before. Thanks for the input guys, I’m happy with the Smithy’s and glad I didn’t go with the turbos. Sent from my iPhone using H.A.M.B.
Sorry for being off topic, but I'm building a sbf powered 47 Ford sedan and am curious about your frame x member. Did you modify it your self or did you buy a kit? Thanks.
I had a builder do all the fab work, I don't believe it is a kit and looks really basic. Hope this helps.
Are you running a transverse spring? I am trying to route the exhaust out the back of my 41 but with tube shocks and the 2" drop Posies transverse spring there is hardly any room to bring it over the axle, thinking I was going to have to go under it which won't look as nice .
This is a simple fix but I'm sure this advise will create the usual disagreements. I bought Smitty's many years ago thinking that it's an old-school name that's been around a long time and should have a perforated core but to my surprise it at the stupid stamped louver core and contrary to what anybody thinks the louvered core is a power Robbing gas sucking piece of crap. It's not the headers causing the drone it's the placement of the muffler. I like the short dumps ahead of the axle but that too is a cause of drone. So here is my suggestion. First sell the Glasspaks and either use the reverse flow walkers or if you can I really like the Hooker Aero chamber mufflers. I got a pair free and put them on my truck that has fenderwell headers and I love the sound .They don't drone and have a great sound that's different from a glass Pak or Flowmaster . The Secret is a crossover H pipe that I see you already have .Thhe most important is to move the mufflers back as as possible Just ahead of the rear end with the tail pipes exiting behind the axel or even better is mounting them all the way behind the rear end if possible. Also the smaller the pipe the louder it is so go with a 21/2" exhaust if possible. . I don't know what size you have now but if its smaller you can step it up to the larger size. One final note on headers. Free flow tube headers improve power and best of all gas economy and with gas getting ridiculous in price per gallon I think it's foolish not to run them. Tri-Y headers are best for street. And as far as the dreaded drone being caused by the headers this is not true. Its the pipe size , muffler location and type of muffler that determines the sound. I will agree that the ram horns are good and on a early car they look correct and work great but it's all in your choices on the rest of the exhaust if it will have the obnoxious drone. Sent from my iPhone using H.A.M.B.
Thanks for the heads up! I will be monitoring gas milage and if I see a big difference (it is nearly $4 a gal here) then I will be looking into the Walker #21314 quiet flow direct OE replacement for the 57 chevy and I believe they are reverse flow. The Smithy's are 30'' long and the casing on the Walker is 27'' long.
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