best way to eliminate drone

[ebbett21]

Hi,
I just had a DIFILLIPO 3'' catback installed a few days ago it runs into 3'' deletion pipes ''no cats'' mated to 4<1 pacemakers ,,
I like the deep ballsy refined tone but after driving half the day today thru stop start traffic and in lower revs it drones alot especially at idle the cabin resonance seems more loud inside than outside , it has abit of boom . Any ideas to rid of the drone and boom? Thinking of Hotdogs were the cats were

[shaunv8]

http://stuffaspergerpeoplelike.com/wp-content/uploads/2008/07/earplugs.jpg

[DR-vyss-108]

http://stuffaspergerpeoplelike.com/wp-content/uploads/2008/07/earplugs.jpg
haha nice one

[ebbett21]

haha nice one

but surely you must need plugs to with a xforce with no rear resi on you tube

[DR-vyss-108]

most people would think so, yeah, i love it

[ebbett21]

most people would think so, yeah, i love it

your car does sound mean as

[Party Pete]

If they are new pipes I would give it a few thousand k's to see how they settle. Then you could think about some dynamat for the cabin if you really like the note outside.

[ebbett21]

If they are new pipes I would give it a few thousand k's to see how they settle. Then you could think about some dynamat for the cabin if you really like the note outside.

only a few days old the exhaust im guessing just bedding in, the note is sweet couldnt really get it any better for a stock internal engine so will just leave it alone ,
only a weekender anyway

[Junkno's SS]

i almost have the same problem as you, and would love to have input on that

hopefully more people can chime on and help us


cheers

[bladerunner]

one trick i tried and it worked but was on a vs 5ltr. i had 2 x 8'' long dogs put on where the rear resonator normally sits but i turned them around so the inside perforated section went against the flow instead of with it. it shut the drone off somewhat and quietened the note just a tad but worked a treat and still left a nice note but as i said that was on a 5ltr with duel 2.5'' pipes so im not sure about an lsx engine but its a suggestion anyway

[white lie]

I know you don't have to run cats, but I think a pair of ballistic 100cpi's will remove the drone. There's a huge difference running them and stock cats, so I think it may help in your instance... Either that or as its just a weekender, harden up!

[255-LS1]

obviously not knowing the answer, but can drone be induced through the tune of the car....

i only ask as many many ppl me included have difilippo systems with no complaints of drone...

[cashie]

Put some cats back in, why are you running without cats anyway?

[ebbett21]

obviously not knowing the answer, but can drone be induced through the tune of the car....

i only ask as many many ppl me included have difilippo systems with no complaints of drone...

ive got no cats with 3'' deletion pipes thats why its abit drony, but wasnt drony at all when i had a xforce 3'' when first had the install however thats life

[cashie]

obviously not knowing the answer, but can drone be induced through the tune of the car....

i only ask as many many ppl me included have difilippo systems with no complaints of drone...

You've got cats.... it won't be the tune.

[XUV]

weld 27 inches of 2 inch exhaust pipe 12 inches from the exhaust tip ..........

[BlueG8GT]

I have a catback system from a company called Solo. The stock exhaust on my G8 GT had 3 mufflers and 2 resonators, the Solo catback has just 1 muffler so there is a decent amount of drone present. They developed a way of dealing with it by welding adjustable J-pipes into the system. Here's a link to their detailed explanation of the product and pics of the J-pipes. Maybe they'd be willing to make you a set of J-pipes for your setup?

http://www.g8board.com/forums/showthread.php?t=28454

[white lie]

Put some cats back in, why are you running without cats anyway?

He's in NZ, cats are optional (unnecessary) extras over there!

[cashie]

He's in NZ, cats are optional (unnecessary) extras over there!

I know they are optional, but I stand by my original question.....Why?

[white lie]

Drone issue aside, would you run them if you didn't have to?
Yes, I understand that the high flowing cats aren't a huge restriction and most likely not noticable from the driver's seat but if you can legally get away with removing a restriction from the exhaust, then why not?

[BOOGER]

I know they are optional, but I stand by my original question.....Why?

Because they're a restriction aren't they? even the most free flowing cats offer some restriction. Plus at about $600 a pair if you can legally remove then you'll save money and remove a restriction. How many people do you think would be running cats here if we were aloud to remove them?

[BOOGER]

What's the go with these "J-pipes"? They seem to be all the go over in the states, has anyone used them here?

[XUV]

true , they're only there to burn any unburnt fuel .

[ebbett21]

Problem being i think difilipo, xforce ect have full systems and test them as a complete system headers, cats, catback. I wonder if you guys in aussie didnt have to run cats, what would diffillipo have in were the cats were? The twin 3'' is pretty big pipes so wondring if a hotdog in there mite pick up some download torque the j pipe worth a look, thnks for the ideas
Question what would sound better cats or specific hotdogs ? either one im 100% sure will get rid of the resonance

[ebbett21]

weld 27 inches of 2 inch exhaust pipe 12 inches from the exhaust tip ..........

ohh yea very good

[ebbett21]

Drone issue aside, would you run them if you didn't have to?
Yes, I understand that the high flowing cats aren't a huge restriction and most likely not noticable from the driver's seat but if you can legally get away with removing a restriction from the exhaust, then why not?

Im not so sure removing cats makes a better note on a twin 3'' system anyone runing pacemaker 4>1s with DF 3'' what cats they using? Im steering towards a set of ballistic cats from sureflo or perforated hotdogs 2.5'' diametre

[ebbett21]

Had hiflo cats fitted today with 3.5'' body to 3'' reducers and the car in my opinion sounds deeper and overall alot less hollow than without cats, the only thing is the DF 3'' is quiet as now have to have the windows down to hear it but does have a awsome note.

[Oztrack Tuning]

Big long 1"7/8 4 into 1s ??
Tune can make a difference if tuned in open loop over the whole map. Rich = drone Lean = less drone.

[ebbett21]

Big long 1"7/8 4 into 1s ??
Tune can make a difference if tuned in open loop over the whole map. Rich = drone Lean = less drone.

pacemaker 4>1 s 3/4 and the drone came from the exhaust bedding in and its completely gone now and with cats fairly quiet but better note. A cam is next:)