Flowmaster 40

shortyno10 · 01-15-2006, 04:20 AM

i have a 40 series muffler on my 4.7L jeep(just the muffler,everything exhaust wise is stock) and at low rpm's it sounds great, but when i get higher rpm's it like hisses. it sounds really high pitched. i cant stand that. is there any way to get rid of this?

RyanWJ · 01-15-2006, 05:07 AM

Quote:

Originally Posted by shortyno10

i have a 40 series muffler on my 4.7L jeep(just the muffler,everything exhaust wise is stock) and at low rpm's it sounds great, but when i get higher rpm's it like hisses. it sounds really high pitched. i cant stand that. is there any way to get rid of this?

get rid of the flowsmsdisasrewer

get amanglaflow

sorry i am durnk

uhhh get a higf flow cat

build an intake using PVC oipes (PM me when i am sober and i can help)

Kolak · 01-15-2006, 07:07 AM

The reason it's hissing is because the rest of your exhaust is a massive restriction. Replace the tailpipe with a 3" mandrel bent unit and also replace the converter with a 3" high flow and the hiss will vanish.

WyoDCWJ · 01-15-2006, 09:16 AM

Does it do that with all flowmasters? I WAS lookin at gettin the 3" system but have desides just to stick with stock piping and get a 50 SUV seires or the 70 Big block seires. Not sure yet. Stock is 2 1/4 right?

J,j.

SGT · 01-15-2006, 11:20 AM

I have 2.5" from high flow cat back through 40 series delta flow flowmaster and to tail pipe. I intend to replace tail pipe with mandrel bent 2.5" later. (BTW, 2.5" is a large improvement over the stock 2.25")

The delta flow 40 is almost as loud as standard 40 outside the vehicle, but much quieter inside. My current setup sounds great, no hissing, only deep sounding.

When I first had the system installed the shop forgot to install the high flow cat. After driving it with original cat and then the high flow cat, with fm 40 installed, I noticed a much deeper sound with the less restrictive cat. So the rest of your exhaust can definately effect the way it sounds.

Also, if you have a flowmaster muffler with 2, 2.25, or 2.5 inch inlet and outlet holes, don't worry. Your muffler shop can cut off the ends and open them up in a few minutes so your muffler isn't smaller than the rest of your exhaust. I know this because the shop that ordered mine ordered the wrong muffler. Good Luck

shortyno10 · 01-15-2006, 03:34 PM

so.....should i just get a whole new 3 inch exhaust with a high flow cat, or can i just get a high flow cat?

shortyno10 · 01-15-2006, 06:04 PM

my exhaust

it sounds just fine sitting there, but when i drive it hisses horribly.

Kolak · 01-15-2006, 07:06 PM

Quote:

Originally Posted by Liberty03

Does it do that with all flowmasters? I WAS lookin at gettin the 3" system but have desides just to stick with stock piping and get a 50 SUV seires or the 70 Big block seires. Not sure yet. Stock is 2 1/4 right?

J,j.

It's not characteristic of the Flowmasters to hiss. It's just that your exhaust is very restricted.

tiki2569 · 01-15-2006, 07:37 PM

I was going to buy a cat back system for mine but i found it much better to do a custom exhaust with dual pipes on my 94 jgcl 5.2 I cant recall what muffler I used but when I figure out how to post a video I will. heres a pic of it. sorry its not too much in detail. been meaning to crawl under for a better shot. somehow now i cant upload pic damn

wusthof · 01-15-2006, 08:30 PM

My 4.7 hisses like a damn too @ WOT. Pisses me off - I shouldn't have cheaped out, saved a few months and got the 3" conversion

. 3 words ~~~ coulda,shoulda,woulda. Wait and upgrade the cat and 3" piping - I'm screwed with a kid on the way, so a new exhaust system ain't gunna happen.................. my 2 cents

derek33 · 01-15-2006, 09:15 PM

that vid clip sounds awsome.

but dude, socks+sandles = nono.

shortyno10 · 01-15-2006, 09:18 PM

haha. i was feeling lazy, and couldnt find my shoes so i put the sandles on.
anyways......so the 3 inch with a high flow cat is the way to go? if it gets rid of the hissing ill be happy.

shortyno10 · 01-15-2006, 09:39 PM

the new pipe that u can see is 2.5 inch. the old was 2.25.

Overland Xpress · 01-15-2006, 10:42 PM

Quote:

Originally Posted by shortyno10

my exhaust

it sounds just fine sitting there, but when i drive it hisses horribly.

Nice clip... sounds mean.

I have 3" from the Y pipe to a Flow 70, then Kolak's mandrel bent 3" tailpipe. No hissing at any RPM. It's surprisingly quiet at high RPM. I definitely recommend the 3" setup.

Hans

tightWJ · 01-15-2006, 10:57 PM

I have full 3" exhaust on mine as well with a Magnaflow cat and muffler http://media.putfile.com/3-inch--exhaust_Audio The sound clip isn't the best quality but you get the idea of the deeper sound with no hissing.

shortyno10 · 01-15-2006, 11:45 PM

whats the magnaflow cat part number?

tightWJ · 01-15-2006, 11:58 PM

94109

rayjj · 01-16-2006, 12:26 AM

Quote:

Originally Posted by derek33

that vid clip sounds awsome.

but dude, socks+sandles = nono.

Damn someone beat me to it lol!

Its funny how that sounds kinda like a mix of a Flowmaster on a 6 and an 8, weird.

I also hate how the 4.7s rev up and down slowly. Makes it sound wimpier than it is. My Durango does the same thing.

shortyno10 · 01-16-2006, 12:28 AM

hahaha! thanks anyways. thanks tightwj.

shortyno10 · 01-16-2006, 12:32 AM

when did jeep start putting the pre cats on the grands?

01-15-2006, 04:20 AM	#1
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	Flowmaster 40 i have a 40 series muffler on my 4.7L jeep(just the muffler,everything exhaust wise is stock) and at low rpm's it sounds great, but when i get higher rpm's it like hisses. it sounds really high pitched. i cant stand that. is there any way to get rid of this?

01-15-2006, 07:07 AM	#3
Kolak Registered Join Date: May 1999 Location: Scottsdale, AZ Posts: 6,228 Thanks: 0 Thanked 7 Times in 7 Posts	The reason it's hissing is because the rest of your exhaust is a massive restriction. Replace the tailpipe with a 3" mandrel bent unit and also replace the converter with a 3" high flow and the hiss will vanish. __________________ 1993 ZJ 5.2: Heavily modded. Currently on display to illustrate how entropy effects the universe. 1998 ZJ 5.9: 18" Tecnomagnesio Rallye wheels, Yokohama AVS S/T tires, all the Kolak goodies, various Mopar/Addco/Edelbrock/Kevin's/Stillen/JKS/K&N stuff. Abstract keying job courtesy of neighborhood hoodlums.

01-15-2006, 11:20 AM	#5
SGT Registered Join Date: Oct 1999 Location: North Carolina Posts: 243 Thanks: 0 Thanked 0 Times in 0 Posts	I have 2.5" from high flow cat back through 40 series delta flow flowmaster and to tail pipe. I intend to replace tail pipe with mandrel bent 2.5" later. (BTW, 2.5" is a large improvement over the stock 2.25") The delta flow 40 is almost as loud as standard 40 outside the vehicle, but much quieter inside. My current setup sounds great, no hissing, only deep sounding. When I first had the system installed the shop forgot to install the high flow cat. After driving it with original cat and then the high flow cat, with fm 40 installed, I noticed a much deeper sound with the less restrictive cat. So the rest of your exhaust can definately effect the way it sounds. Also, if you have a flowmaster muffler with 2, 2.25, or 2.5 inch inlet and outlet holes, don't worry. Your muffler shop can cut off the ends and open them up in a few minutes so your muffler isn't smaller than the rest of your exhaust. I know this because the shop that ordered mine ordered the wrong muffler. Good Luck __________________ 95 ZJ, V8, 4" lift, RS 9000's, 32x11.50 BFG, Front Guard, Land Master 190 Lamps, Tail Light Guards, Roof Mounted Spare, Bumper Trim, High Flow Cat, Flowmaster 40

01-15-2006, 09:39 PM	#13
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	the new pipe that u can see is 2.5 inch. the old was 2.25. __________________ 99 Grand Cherokee V8 4" lift Carolina Driveshaft k&n FIPK full 3" exhaust with super 40 series muffler

01-15-2006, 10:57 PM	#15
tightWJ BOOST=FUN Join Date: Dec 2004 Location: Jacksonville, Florida Posts: 1,368 Thanks: 0 Thanked 0 Times in 0 Posts	I have full 3" exhaust on mine as well with a Magnaflow cat and muffler http://media.putfile.com/3-inch--exhaust_Audio The sound clip isn't the best quality but you get the idea of the deeper sound with no hissing. __________________ -CHRIS- 06' SRT8GC Inferno Red- Zex Nitrous- RDP tune- SRT Max cam- Kooks headers- Bullet resonators- 5" Cannon tips- Innovate LC-1/XD-16 wideband- Predator- 176 tstat- Custom 4" CAI- 2wd/ESP switch- 8K HID kit- RM360 antenna- Pioneer F90- 20% tint- Eibach springs- Color matched wheels 11.79 @ 115.92 99' WJ Limited- Kenne Bell Supercharged- Gone but not forgotten! 92' S10 Prostreet 800hp/1000hp+ on juice- 383 stroker- all forged- 871 blower- tubbed- backhalfed- 9" Ford

01-15-2006, 09:16 AM	#4
WyoDCWJ Registered Join Date: Oct 2004 Posts: 330 Thanks: 0 Thanked 0 Times in 0 Posts	Does it do that with all flowmasters? I WAS lookin at gettin the 3" system but have desides just to stick with stock piping and get a 50 SUV seires or the 70 Big block seires. Not sure yet. Stock is 2 1/4 right? J,j.

01-15-2006, 03:34 PM	#6
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	so.....should i just get a whole new 3 inch exhaust with a high flow cat, or can i just get a high flow cat?

01-15-2006, 06:04 PM	#7
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	my exhaust it sounds just fine sitting there, but when i drive it hisses horribly.

01-15-2006, 07:37 PM	#9
tiki2569 Registered Join Date: Nov 2005 Location: Rhode Island Posts: 131 Thanks: 0 Thanked 0 Times in 0 Posts	I was going to buy a cat back system for mine but i found it much better to do a custom exhaust with dual pipes on my 94 jgcl 5.2 I cant recall what muffler I used but when I figure out how to post a video I will. heres a pic of it. sorry its not too much in detail. been meaning to crawl under for a better shot. somehow now i cant upload pic damn

01-15-2006, 08:30 PM	#10
wusthof Registered Join Date: Oct 2004 Location: Van. BC Canada Posts: 423 Thanks: 0 Thanked 0 Times in 0 Posts	My 4.7 hisses like a damn too @ WOT. Pisses me off - I shouldn't have cheaped out, saved a few months and got the 3" conversion . 3 words ~~~ coulda,shoulda,woulda. Wait and upgrade the cat and 3" piping - I'm screwed with a kid on the way, so a new exhaust system ain't gunna happen.................. my 2 cents

01-15-2006, 09:15 PM	#11
derek33 Registered Join Date: Aug 2004 Posts: 119 Thanks: 0 Thanked 0 Times in 0 Posts	that vid clip sounds awsome. but dude, socks+sandles = nono.

01-15-2006, 09:18 PM	#12
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	haha. i was feeling lazy, and couldnt find my shoes so i put the sandles on. anyways......so the 3 inch with a high flow cat is the way to go? if it gets rid of the hissing ill be happy.

01-15-2006, 11:45 PM	#16
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	whats the magnaflow cat part number? __________________ 99 Grand Cherokee V8 4" lift Carolina Driveshaft k&n FIPK full 3" exhaust with super 40 series muffler

01-15-2006, 11:58 PM	#17
tightWJ BOOST=FUN Join Date: Dec 2004 Location: Jacksonville, Florida Posts: 1,368 Thanks: 0 Thanked 0 Times in 0 Posts	94109 __________________ -CHRIS- 06' SRT8GC Inferno Red- Zex Nitrous- RDP tune- SRT Max cam- Kooks headers- Bullet resonators- 5" Cannon tips- Innovate LC-1/XD-16 wideband- Predator- 176 tstat- Custom 4" CAI- 2wd/ESP switch- 8K HID kit- RM360 antenna- Pioneer F90- 20% tint- Eibach springs- Color matched wheels 11.79 @ 115.92 99' WJ Limited- Kenne Bell Supercharged- Gone but not forgotten! 92' S10 Prostreet 800hp/1000hp+ on juice- 383 stroker- all forged- 871 blower- tubbed- backhalfed- 9" Ford

01-16-2006, 12:28 AM	#19
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	hahaha! thanks anyways. thanks tightwj. __________________ 99 Grand Cherokee V8 4" lift Carolina Driveshaft k&n FIPK full 3" exhaust with super 40 series muffler

01-16-2006, 12:32 AM	#20
shortyno10 Registered Join Date: Feb 2005 Location: Oxnard, CA Posts: 440 Thanks: 0 Thanked 0 Times in 0 Posts	when did jeep start putting the pre cats on the grands? __________________ 99 Grand Cherokee V8 4" lift Carolina Driveshaft k&n FIPK full 3" exhaust with super 40 series muffler

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