side exhaust?
6th Gear Member
Joined: Mar 2006
Posts: 5,373
From: Wichita, Ks
RE: side exhaust?
damnit...we need someone in here that everyone knows and believes and trusts that actually knows wtf they are talkin about. would someone please figure out and explain to this guy whats goin on
5th Gear Member
Joined: Jan 2006
Posts: 2,645
From: So-Cal
RE: side exhaust?
ORIGINAL: amrcnidyot
damnit...we need someone in here that everyone knows and believes and trusts that actually knows wtf they are talkin about. would someone please figure out and explain to this guy whats goin on
damnit...we need someone in here that everyone knows and believes and trusts that actually knows wtf they are talkin about. would someone please figure out and explain to this guy whats goin on
Stock 5.0's had 2.25 inch pipes
Modular engines don't really follow the old rules of the pushrod engines, and they like to have slightly larger pipes
The Godfather
Joined: Sep 2005
Posts: 15,480
From: Temple, Texas
RE: side exhaust?
^^^^He's right, your engine needs backpressure to function properly, because why do you think when you have an exhaust leak, espeically around the headers, it's so important to get that fixed? It's because the leak causes a serious lack of back pressure which in turn kills hp, and hurts mpg.
4th Gear Member
Joined: Jul 2005
Posts: 1,008
From: Tampa, FL
RE: side exhaust?
ORIGINAL: BeachStang04
dude twisters right man. You will loose low end torque but also gain some in the highend, if you do not have enough backpressure you will loose horsepower thats why it is recommened to go with 2.5 unless your going f/i or having some heavy internal work done.
dude twisters right man. You will loose low end torque but also gain some in the highend, if you do not have enough backpressure you will loose horsepower thats why it is recommened to go with 2.5 unless your going f/i or having some heavy internal work done.
5th Gear Member
Joined: Mar 2004
Posts: 3,594
From:
RE: side exhaust?
plain and simple. it doesn't matter if the engine is built or not. exhaust gasses have to follow Gaseous Laws. take some Chemistry to learn that
exhaust leaving the cylinder is under high pressure. 2.5" exhaust creats a lower pressure area than 2" duals. as we all know gasses move from an area of high pressure to an area of low pressure.
is 3" too big? no. is it needed? no.
dual 2.25" is fine as long as it's mandrel bent. 2.5" dual is fine and you will not lose lowend torque with dual 2.5" or dual 3", if you do it will be no more than 3-5ftlbs but gain torque on the order of 7-10 in the mids to high rpm's. you gain high end power which makes the torque curve more curved. stock setups have a very flat torque curve. because you are making the curve more arched it will feel like you lost low end with your butt dyno when in reality you still have the same lowend but higher mid and high end power
a guy called slvr2000stang from 3.8mustang and v6power gained 12rwhp and 10ftlbs of torque when he went to 3" duals from 2.5" duals.
i have quite a few years of engine building experience behind me and have never once witnessed any car lose torque on a dyno from running larger exhaust.
all in all the best exhaust setup for 90 degree even fire V6's is LT's feeding 3-3.5" single exhaust. Smokey Yunick and Grumpy Jenkins confirmed this in the 70's with their work on even fire Buicks and semi-even fire 265" Chebby V6
exhaust leaving the cylinder is under high pressure. 2.5" exhaust creats a lower pressure area than 2" duals. as we all know gasses move from an area of high pressure to an area of low pressure.
is 3" too big? no. is it needed? no.
dual 2.25" is fine as long as it's mandrel bent. 2.5" dual is fine and you will not lose lowend torque with dual 2.5" or dual 3", if you do it will be no more than 3-5ftlbs but gain torque on the order of 7-10 in the mids to high rpm's. you gain high end power which makes the torque curve more curved. stock setups have a very flat torque curve. because you are making the curve more arched it will feel like you lost low end with your butt dyno when in reality you still have the same lowend but higher mid and high end power
a guy called slvr2000stang from 3.8mustang and v6power gained 12rwhp and 10ftlbs of torque when he went to 3" duals from 2.5" duals.
i have quite a few years of engine building experience behind me and have never once witnessed any car lose torque on a dyno from running larger exhaust.
all in all the best exhaust setup for 90 degree even fire V6's is LT's feeding 3-3.5" single exhaust. Smokey Yunick and Grumpy Jenkins confirmed this in the 70's with their work on even fire Buicks and semi-even fire 265" Chebby V6
5th Gear Member
Joined: Mar 2004
Posts: 3,594
From:
RE: side exhaust?
ORIGINAL: jthorn9
^^^^He's right, your engine needs backpressure to function properly, because why do you think when you have an exhaust leak, espeically around the headers, it's so important to get that fixed? It's because the leak causes a serious lack of back pressure which in turn kills hp, and hurts mpg.
^^^^He's right, your engine needs backpressure to function properly, because why do you think when you have an exhaust leak, espeically around the headers, it's so important to get that fixed? It's because the leak causes a serious lack of back pressure which in turn kills hp, and hurts mpg.
5th Gear Member
Joined: Jan 2006
Posts: 2,645
From: So-Cal
RE: side exhaust?
ORIGINAL: cobra232
a guy called slvr2000stang from 3.8mustang and v6power gained 12rwhp and 10ftlbs of torque when he went to 3" duals from 2.5" duals.
a guy called slvr2000stang from 3.8mustang and v6power gained 12rwhp and 10ftlbs of torque when he went to 3" duals from 2.5" duals.
I spoke to him tonight
5th Gear Member
Joined: Mar 2004
Posts: 3,594
From:
RE: side exhaust?
ORIGINAL: deezelnut
it's on now
let's see, 1970 Cougar Eliminator. 351C 13.5:1 compression. 4" exhaust, carbed. can't remember exact numbers, it was like 500+ rwhp. 1980 Rabbit truck. 22.2:1 compression, 42 lbs of boost. 4' exhaust. 1973 charger. 426 hemi. 4' exhaust. 625 something rwhp. but since those probably don't count. here's this
1976 TA. 515 CI SD bored .030 over, dual holley 750 dumpers and twin turbos. 1300 rwhp. i helped on that one. 5' exhaust. none of these cars had mufflers. so i will say it again.
[IMG]local://upfiles/42520/6CFF89B1A9D84C21A617F822889BDB80.jpg[/IMG]
ORIGINAL: Twister
dood, how many cars have you built? you are talking out of your *** and you don't even realize it. Bigger is not always better, ask any guy that runs a carb about that. Thinking that backpreasure is not an important thing is a ricer thought.
ORIGINAL: deezelnut
you mean slowmaster.
why do you think race cars don't have mufflers? are people really this retarded
[IMG]local://upfiles/42520/8D08EF4251DE44F69D952CD04DEA163D.jpg[/IMG]
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[IMG]local://upfiles/42520/64CB484BAD134013B49256C7A9C630BC.jpg[/IMG]
ORIGINAL: Twister
what are you smoking? you can loose power and torque from not enough backpreasure! I have seen dyno sheets that proves that you can loose torque and horsepower by running duels on a stock 3.8.
Even Flowmaster says the same http://www.flowmastermufflers.com/backpressure.html
ORIGINAL: cobra232
you want Zero backpressure in an exhaust.
backpressure does nothing but make the engine work to breath which takes HP to do.
why do people think backpressure is good is beyond me
ORIGINAL: Twister
duel exhaust on a stock V6 (3.8) will produce less hp and torque due to not enough backpreasure. Add the extra bends of a side exhaust kit, and you will reduce the flow....
duel exhaust on a stock V6 (3.8) will produce less hp and torque due to not enough backpreasure. Add the extra bends of a side exhaust kit, and you will reduce the flow....
backpressure does nothing but make the engine work to breath which takes HP to do.
why do people think backpressure is good is beyond me
Even Flowmaster says the same http://www.flowmastermufflers.com/backpressure.html
why do you think race cars don't have mufflers? are people really this retarded
[IMG]local://upfiles/42520/8D08EF4251DE44F69D952CD04DEA163D.jpg[/IMG]
[IMG]local://upfiles/42520/180590D0C0D9413CB5FD4F671F68B57D.jpg[/IMG]
[IMG]local://upfiles/42520/6F90034317274A05B746D1B747DDF41D.jpg[/IMG]
[IMG]local://upfiles/42520/64CB484BAD134013B49256C7A9C630BC.jpg[/IMG]
let's see, 1970 Cougar Eliminator. 351C 13.5:1 compression. 4" exhaust, carbed. can't remember exact numbers, it was like 500+ rwhp. 1980 Rabbit truck. 22.2:1 compression, 42 lbs of boost. 4' exhaust. 1973 charger. 426 hemi. 4' exhaust. 625 something rwhp. but since those probably don't count. here's this
1976 TA. 515 CI SD bored .030 over, dual holley 750 dumpers and twin turbos. 1300 rwhp. i helped on that one. 5' exhaust. none of these cars had mufflers. so i will say it again.
[IMG]local://upfiles/42520/6CFF89B1A9D84C21A617F822889BDB80.jpg[/IMG]
i'm about to swap an 85 jetta turbo setup onto an 80 truck. i know i can have the injection pump reworked to flow enough to support 7,000rpm's but i don't know where.
i was thinking more along the lines of 30psi on my setup with a cam and ported head and 3" exhaust. not sure which turbo to go with. i'll use the stock one for now but i was thinkin about a TD05H 14G or a GT25.
the jetta is on it's last leg but ran damn good for awhile on salvaged deepfryer oil/used engine/tranny oil mix
I ♥ Acer
Joined: Jul 2006
Posts: 1,618
From:
RE: side exhaust?
ORIGINAL: cobra232
i'm about to swap an 85 jetta turbo setup onto an 80 truck. i know i can have the injection pump reworked to flow enough to support 7,000rpm's but i don't know where.
i was thinking more along the lines of 30psi on my setup with a cam and ported head and 3" exhaust. not sure which turbo to go with. i'll use the stock one for now but i was thinkin about a TD05H 14G or a GT25.
the jetta is on it's last leg but ran damn good for awhile on salvaged deepfryer oil/used engine/tranny oil mix
[/quote]
do you like 11s on slicks? it runs like an evil little ****. but it is very unforgiving. one bad spot in the road and you have 42 PSI and no control. other than that it is a riot to drive. fun and fast. but it is tiny
2nd Gear Member
Joined: Jul 2006
Posts: 293
From:
RE: side exhaust?
ORIGINAL: deezelnut
do you like 11s on slicks? it runs like an evil little ****. but it is very unforgiving. one bad spot in the road and you have 42 PSI and no control. other than that it is a riot to drive. fun and fast. but it is tiny
ORIGINAL: cobra232
on a side note how's that VW truck run?
i'm about to swap an 85 jetta turbo setup onto an 80 truck. i know i can have the injection pump reworked to flow enough to support 7,000rpm's but i don't know where.
i was thinking more along the lines of 30psi on my setup with a cam and ported head and 3" exhaust. not sure which turbo to go with. i'll use the stock one for now but i was thinkin about a TD05H 14G or a GT25.
the jetta is on it's last leg but ran damn good for awhile on salvaged deepfryer oil/used engine/tranny oil mix
on a side note how's that VW truck run?
i'm about to swap an 85 jetta turbo setup onto an 80 truck. i know i can have the injection pump reworked to flow enough to support 7,000rpm's but i don't know where.
i was thinking more along the lines of 30psi on my setup with a cam and ported head and 3" exhaust. not sure which turbo to go with. i'll use the stock one for now but i was thinkin about a TD05H 14G or a GT25.
the jetta is on it's last leg but ran damn good for awhile on salvaged deepfryer oil/used engine/tranny oil mix