Dual or Single Exhaust? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Eagle1 · 01-31-2003, 12:33 PM

I have a recently rebuild 307 engine and im thinking about doing the exhaust. Which would be better a 2” dual exhaust with dynomax super turbos, or a single 2 ¼-½" with one super turbo.
Thanks Eagle

HotRod929 · 01-31-2003, 12:43 PM

Duals!!!

HotRod

lukecp · 01-31-2003, 12:45 PM

How loud do you want it to be? The dual exhaust would be a bit quieter because it has 2 mufflers, while the single would have one. I would be tempted to get a single 2.5" pipe, and a Dynomax Hemi Turbo muffler, which is like a quiter Super Turbo. Power will be about the same for either system.

barn9 · 01-31-2003, 12:53 PM

Nothin' sounds better than a nice set of duals. Single exhaust is for granny's car.

MU72 · 01-31-2003, 02:10 PM

barn's right, single exhaust is for nancy boys. Go for the duals. You might want to look in to a set of glasspacks. Lots of people don't like the sound. Personally, I don't think you can beat that sound on these old trucks. There are many different option you can go with in the packs. I used to have a set of 24" packs on my truck. Not too loud just a nice rumble but talked when you put you foot in it. Best of all, they are cheap.

Longhorn Man · 01-31-2003, 02:28 PM

As much as I like a set of chrome tips hanging out from under the bumper, a single pipe is cheaper, and performace wise, your 307 (I asume stock) is not a fire breather and little gains would be seen with a set of pipes verses a good single set up.
Onless you are planning on a larger engine in the future, and if you are trying to watch the out going cash flow, (or the wife is watching that for you) I think i would go with a single pipe system.

JimKshortstep4x4 · 01-31-2003, 02:38 PM

Duals will give you less restrictive exhaust, even with one 2 1/2" exhaust.

Cross sectional area of a 2 1/2 " pipe is 4.9 square inches.

With 2" duals, the area is 6.3 square inches.

Jim

crazy longhorn · 01-31-2003, 02:41 PM

I am a fan of duals! I ran 2" pipe , with H pipe , superturbos, & side exit tail pipes(behind the wheels) on a 305 powered flatbed. The system sounded nice......not too loud, but you could hear it. the H pipe in the system will mellow the note & give a more "tuned" sound......also helps with the low & midrange tork. good luck,crazyL

Longhorn Man · 01-31-2003, 02:50 PM

JimKshortstep4x4 is right, however, you can go too far with pipe size. It is not as dramatic as picking a huge tube header, but too much pipe Cross sectional area will kil your lower end torque...which is all a 307 has going for it.

crazy longhorn · 01-31-2003, 02:54 PM

2" pipe should be fine on the 307......I wouldnt go any bigger tho........crazyL

3damnboyz · 01-31-2003, 03:09 PM

twice pipes!

gman · 01-31-2003, 03:20 PM

Don't mean to steal your post eagle.....

Would 2 inch duals with the "H" pipe be the way to go for a 72 4X4 also? No headers yet........not sure about them. Can you add headers later to a setup like this if you choose to do so? Suggestions? Stock 350.......will be rebuilt soon with a bit more goodies in it but no race car intentions.

crazy longhorn · 01-31-2003, 03:31 PM

gman, the 4x4s take a little more power to turn everything......I would run 2" on a pretty mild 350. If it was a 2wd, I would think about going 2 1/4" on the pipe. As far as the headers, due to the "fun way" the 4x4 pipes lace in, i would install them before the exhaust was done to save on headaches later. crazyL

gangforward · 01-31-2003, 04:04 PM

2 pipes. 2 cool.

barn9 · 01-31-2003, 04:22 PM

I had duals (with an H pipe) on another truck that had a 307 in it, and I never regretted it one bit. I had the duals with H on my current truck before I changed to headers, and the change was no problem. Anyone that knows his stuff can mate them up with no problem. And I also feel very strongly that any dual system should have either the H or an X pipe. I also like glasspacks, love the sweet sound of dual glasspacks rumbling! Single exhaust is just plain LAME !

crazy longhorn · 01-31-2003, 04:38 PM

I have mated headers to an existing system, but just as an observation(from working in an exhaust shop)....once upon a time! The systems are much cleaner looking, & will have a couple less splices in them if all the work is fitted/ done at the same time.....crazyL

Eagle1 · 01-31-2003, 06:12 PM

Thanks Guys for the replys the reason I was asking was the exhaust is going on my sisters car, its a 69 chevelle malibu right now it has a 2.25" single exhuast with a stock muffler and catalytic converter someone put on, before we bough the car. She does not want to be loud. But price wise how much would a complete 2" dual exhaust be with two dynomax super turbos vs.
a single 2.5" exhaust with one dynomax super turbo. The whole exhaust needs to be done from the exhuast manifolds to the muffler(s).
Thanks Eagle

crazy longhorn · 01-31-2003, 06:20 PM

Price would depend on the area & how much competition there is in exhaust work. In my area, I would say in the range of $250-300 on the duals, & the single exhaust might be $75 cheaper. good luck, crazyL

cheyenne10 · 02-01-2003, 03:06 AM

Does anyone try to route exhaust and H pipe so the tranny and transfer case if so equiped can be removed without butchering exhaust? Any tricks?

jhwkns · 02-01-2003, 12:49 PM

If you put a coupler (flange) on the crossover pipe the exhaust can be easily dropped out of the way.

71-longbed · 02-01-2003, 01:48 PM

get duals .....straight out the back .....

71k5 · 02-01-2003, 03:14 PM

I think I'll try a single 3" sustem with a 3" flowmaster when I get my big block in; out the side behind the rear wheel because I tow so much.

01-31-2003, 12:33 PM	#1
Eagle1 Registered User Join Date: Sep 2002 Location: SLC, UT Posts: 13	Dual or Single Exhaust? I have a recently rebuild 307 engine and im thinking about doing the exhaust. Which would be better a 2” dual exhaust with dynomax super turbos, or a single 2 ¼-½" with one super turbo. Thanks Eagle __________________ 77 C10 truck 355/TH350, 10:1 KB's, COMP XE256H, EDELBROCK PERFORMER, CARTER 600 CARB.

01-31-2003, 12:43 PM	#2
HotRod929 Registered User Join Date: Mar 2002 Location: Bondurant, IA but in Worcester, MA for school Posts: 767	Duals!!! HotRod __________________ 1970 Chevy C-20 350 V-8 Turbo 350 w/ shift kit Dana 60 w/ 4.10 gears AND Powr-Loc POSI New Additions: Summit Headers 135amp alternator Proform HEI Edelbrock 1406 600cfm carb Sunpro Tach Powr-Loc POSI Edelbrock Performer RPM Intake MSD 6A Ignition Box AIM: HotRod929 Visit My Site: http://1970chevy.netfirms.com/

01-31-2003, 12:45 PM	#3
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	How loud do you want it to be? The dual exhaust would be a bit quieter because it has 2 mufflers, while the single would have one. I would be tempted to get a single 2.5" pipe, and a Dynomax Hemi Turbo muffler, which is like a quiter Super Turbo. Power will be about the same for either system. __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

01-31-2003, 12:53 PM	#4
barn9 Half a bubble off! Join Date: Jun 2000 Location: Winfield, Ks, USA Posts: 5,588	Nothin' sounds better than a nice set of duals. Single exhaust is for granny's car. __________________ Just call me LB. '71 Cheyenne, 402BB, hauls blondes, brunettes, or redheads.

01-31-2003, 02:10 PM	#5
MU72 Registered User Join Date: Sep 2002 Location: Maryville Mo Posts: 122	barn's right, single exhaust is for nancy boys. Go for the duals. You might want to look in to a set of glasspacks. Lots of people don't like the sound. Personally, I don't think you can beat that sound on these old trucks. There are many different option you can go with in the packs. I used to have a set of 24" packs on my truck. Not too loud just a nice rumble but talked when you put you foot in it. Best of all, they are cheap. __________________ 72 Cheyenne 1/2T LWB original ochre/white 09 Silverado ECSB 76 International ScoutII

01-31-2003, 02:28 PM	#6
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	As much as I like a set of chrome tips hanging out from under the bumper, a single pipe is cheaper, and performace wise, your 307 (I asume stock) is not a fire breather and little gains would be seen with a set of pipes verses a good single set up. Onless you are planning on a larger engine in the future, and if you are trying to watch the out going cash flow, (or the wife is watching that for you) I think i would go with a single pipe system.

01-31-2003, 02:38 PM	#7
JimKshortstep4x4 Senior Member Join Date: Jul 2001 Location: Muskegon,MI,USA Posts: 6,026	Duals will give you less restrictive exhaust, even with one 2 1/2" exhaust. Cross sectional area of a 2 1/2 " pipe is 4.9 square inches. With 2" duals, the area is 6.3 square inches. Jim

01-31-2003, 02:41 PM	#8
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	I am a fan of duals! I ran 2" pipe , with H pipe , superturbos, & side exit tail pipes(behind the wheels) on a 305 powered flatbed. The system sounded nice......not too loud, but you could hear it. the H pipe in the system will mellow the note & give a more "tuned" sound......also helps with the low & midrange tork. good luck,crazyL __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

01-31-2003, 02:50 PM	#9
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	JimKshortstep4x4 is right, however, you can go too far with pipe size. It is not as dramatic as picking a huge tube header, but too much pipe Cross sectional area will kil your lower end torque...which is all a 307 has going for it.

01-31-2003, 02:54 PM	#10
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	2" pipe should be fine on the 307......I wouldnt go any bigger tho........crazyL __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

01-31-2003, 03:09 PM	#11
3damnboyz Registered User Join Date: Dec 2002 Location: east texas Posts: 42	twice pipes! __________________ 72 short wide 55 stepside- 2nd generation "come on honey, we need more old trucks to fix up for the boys to drive, they will be driving before ya know it!"

01-31-2003, 03:20 PM	#12
gman Registered User Join Date: Nov 2000 Location: Ogden, Utah Posts: 290	Don't mean to steal your post eagle..... Would 2 inch duals with the "H" pipe be the way to go for a 72 4X4 also? No headers yet........not sure about them. Can you add headers later to a setup like this if you choose to do so? Suggestions? Stock 350.......will be rebuilt soon with a bit more goodies in it but no race car intentions. __________________ 72 Chevy SWB Custom Deluxe K10, 350/SM465, PS, PB, Fact. Air 2000 Harley...Wide Glide

01-31-2003, 03:31 PM	#13
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	gman, the 4x4s take a little more power to turn everything......I would run 2" on a pretty mild 350. If it was a 2wd, I would think about going 2 1/4" on the pipe. As far as the headers, due to the "fun way" the 4x4 pipes lace in, i would install them before the exhaust was done to save on headaches later. crazyL __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

01-31-2003, 04:04 PM	#14
gangforward Hootis is as Hootis does... Join Date: Nov 2002 Location: Southern Georgia Posts: 500	2 pipes. 2 cool. __________________ 67 C10 LWB Fleet, 383, TH400, PS, 4BL-Holley, Headers & 3" Exhaust, 3" drop front, 4" rear springs, ECI shock relocate, Panhard Bar kit, wheels & tires 1995 Z28 Convertible - Borla, K&N, Lingenfelter Motor, C6 Wheels & Tires 1990 2500 4x4 Suburban 3" Catbac System, K&N, 2" Lift, Wheels, Tires

01-31-2003, 04:22 PM	#15
barn9 Half a bubble off! Join Date: Jun 2000 Location: Winfield, Ks, USA Posts: 5,588	I had duals (with an H pipe) on another truck that had a 307 in it, and I never regretted it one bit. I had the duals with H on my current truck before I changed to headers, and the change was no problem. Anyone that knows his stuff can mate them up with no problem. And I also feel very strongly that any dual system should have either the H or an X pipe. I also like glasspacks, love the sweet sound of dual glasspacks rumbling! Single exhaust is just plain LAME ! __________________ Just call me LB. '71 Cheyenne, 402BB, hauls blondes, brunettes, or redheads.



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01-31-2003, 04:38 PM	#16
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	I have mated headers to an existing system, but just as an observation(from working in an exhaust shop)....once upon a time! The systems are much cleaner looking, & will have a couple less splices in them if all the work is fitted/ done at the same time.....crazyL __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

01-31-2003, 06:12 PM	#17
Eagle1 Registered User Join Date: Sep 2002 Location: SLC, UT Posts: 13	Thanks Guys for the replys the reason I was asking was the exhaust is going on my sisters car, its a 69 chevelle malibu right now it has a 2.25" single exhuast with a stock muffler and catalytic converter someone put on, before we bough the car. She does not want to be loud. But price wise how much would a complete 2" dual exhaust be with two dynomax super turbos vs. a single 2.5" exhaust with one dynomax super turbo. The whole exhaust needs to be done from the exhuast manifolds to the muffler(s). Thanks Eagle __________________ 77 C10 truck 355/TH350, 10:1 KB's, COMP XE256H, EDELBROCK PERFORMER, CARTER 600 CARB.

01-31-2003, 06:20 PM	#18
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	Price would depend on the area & how much competition there is in exhaust work. In my area, I would say in the range of $250-300 on the duals, & the single exhaust might be $75 cheaper. good luck, crazyL __________________ 69 longhorn,4" chop,3/5 drop, 1/2 ton suspension/disc brakes,1 1/2" body drop,steel tilt clip, 5.3/Edelbrock rpm intake/600 carb, Hooker streetrod shorties,2 1/2" exhaust/ H pipe/50's Flows , 6 spd Richmond trans,12 bolt/ 3.40 gears....

02-01-2003, 03:06 AM	#19
cheyenne10 Senior Member Join Date: Apr 2000 Location: Oregon Posts: 2,512	tranny interference Does anyone try to route exhaust and H pipe so the tranny and transfer case if so equiped can be removed without butchering exhaust? Any tricks? __________________ Bob

02-01-2003, 12:49 PM	#20
jhwkns Registered Cruiser Join Date: May 2002 Location: Las Vegas NV Posts: 2,230	If you put a coupler (flange) on the crossover pipe the exhaust can be easily dropped out of the way. __________________ I intend to live forever. So far, so good.

02-01-2003, 01:48 PM	#21
71-longbed Its Magically Delicious Join Date: Jan 2003 Location: oregon Posts: 2,398	get duals .....straight out the back .....

02-01-2003, 03:14 PM	#22
71k5 Registered User Join Date: Feb 2002 Location: Manchester, PA Posts: 138	I think I'll try a single 3" sustem with a 3" flowmaster when I get my big block in; out the side behind the rear wheel because I tow so much.

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