View Poll Results: what's your choice will be ?
True Duals
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209
65.11%
ORY & Catback
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112
34.89%
Voters: 321. You may not vote on this poll
poll: true duals VS Ypipe & cat-back?.....
#81
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I think there is a bit left on the table with the tuning...you'd be surprised at how the PCM reacts to mods like these. It isn't exactly what you'd expect, and if they weren't messing with the VE table to get the tune in line, they weren't doing it right.
It is a comparisson, but I would not call it a good comparisson. At least not truly apples to apples IMO.
It is a comparisson, but I would not call it a good comparisson. At least not truly apples to apples IMO.
#82
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Originally Posted by 300bhp/ton
Cheers for posting that dyno chart. It just goes to show that sometimes mass public opinion isn't always correct ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
I would think this is due to one of two reasons. First off lots of people put the cutouts before the mid pipe, thus totally removing the scavenging that can be achieved with it. The other thing it the exhaust pressure wave, the cutouts may have been having a negative affect on it.
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I would think this is due to one of two reasons. First off lots of people put the cutouts before the mid pipe, thus totally removing the scavenging that can be achieved with it. The other thing it the exhaust pressure wave, the cutouts may have been having a negative affect on it.
#83
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Are you looking for sound or performance?
I can make a Y-pipe system work as well as any true dual with less clearance problems for either drag applicaiton or road race. System design of individual components will have a greater determining role in net HP than being a Y or true dual configuration alone.
I can make a Y-pipe system work as well as any true dual with less clearance problems for either drag applicaiton or road race. System design of individual components will have a greater determining role in net HP than being a Y or true dual configuration alone.
Last edited by oxidizr; 02-24-2006 at 08:03 PM.
#84
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Originally Posted by oxidizr
System design of individual components will have a greater determining role in net HP than being a Y or true dual configuration alone.
I agree. Especially with some of the Y-pipes out there. I think the Flowmaster collector looks and flows the best.
I'm lookin to try a X-setup. What mufflers would you use for max HP and not losing any TQ too?
#85
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Let me say this. I went from true duals basicly the same as the TSP system to a pacesetter y pipe with a ported merge and a Hooker catback and it lost noticeable power. I had to put a Hotcam in my car just to get it running as quick and fast as it did with the duals and stock cam. Even a friend of mine that rode in the car commented on how it didnt pull nearly as hard as it did before.
#86
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Just put my true duals on tonight! Yeah, it has a better pull, and more down low than my hooker ORY and dynomax bullet. I guess i had basically a "loud mouth" system turned out before the axle. I thought that little invention was going to be good for more powa, but the TSP system kicked its ***. I can feel it kick a lot harder!
#89
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Originally Posted by Full-Force
Let me say this. I went from true duals basicly the same as the TSP system to a pacesetter y pipe with a ported merge and a Hooker catback and it lost noticeable power. I had to put a Hotcam in my car just to get it running as quick and fast as it did with the duals and stock cam. Even a friend of mine that rode in the car commented on how it didnt pull nearly as hard as it did before.
#90
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Originally Posted by 00SS4780
I have a local friend who had a custom td x setup under the axle. He had some bolt-on's and a T-rex cam. He made 406 with it. He then decided to put on a y-pipe system like mine and a cutout. Because of ground clearence issues. He redyno'd the car and made the same amount of hp. Now the x wasn't a brand name but still I was shocked it made the same.
#91
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I wish I remember where I read this, but it was said by a respected source. A good single pipe 3" catback is good for zero loss to....**** I forget the exact number....around 375 rwhp.
And personally, I hate spending money on parts that only boast of "zero loss".
Right now my car is stock but I have a set of Kooks LT's with a catted y-pipe going on soon. Presently, I'm leaning toward keeping the stock catback and just installing a cutout. Or I might spring for a Hooker catback.
I just don't want to deal with some of the drawbacks of dual systems. In particular, fitment and clearance can be an issue, as well as cost, and/or the high noise level.
JM2C
And personally, I hate spending money on parts that only boast of "zero loss".
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Right now my car is stock but I have a set of Kooks LT's with a catted y-pipe going on soon. Presently, I'm leaning toward keeping the stock catback and just installing a cutout. Or I might spring for a Hooker catback.
I just don't want to deal with some of the drawbacks of dual systems. In particular, fitment and clearance can be an issue, as well as cost, and/or the high noise level.
JM2C
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#92
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The ONLY way I would ever go back to a single exhaust is like this.
I will build my own mandrel bent 3" Y pipe using a Flowmaster dual 3" in single 4" out into a 4" pipe with 4" cutout before it goes over the axle and then reduce it to 3" of the cutout and over the axle with whatever catback.
So basicly just replace the I pipe of a catback with a 4" piece and cutout.
A single 3" pipe is nowhere enough for one of these engines. Ive had 5 exhaust on my car now duals and catbacks. The seat of pants aint even close to the same. My trap speeds were not even close to the sme either.
I will build my own mandrel bent 3" Y pipe using a Flowmaster dual 3" in single 4" out into a 4" pipe with 4" cutout before it goes over the axle and then reduce it to 3" of the cutout and over the axle with whatever catback.
So basicly just replace the I pipe of a catback with a 4" piece and cutout.
A single 3" pipe is nowhere enough for one of these engines. Ive had 5 exhaust on my car now duals and catbacks. The seat of pants aint even close to the same. My trap speeds were not even close to the sme either.
#93
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4" is overkill and VERY heavy...
Some things to look at:
Flow capacity-
3.0" diameter pipe = 3.14159 * 1.5 * 1.5 = 7.0685 sq in
3.5" diameter pipe = 3.14159 * 1.75 * 1.75 = 9.6211 sq in
4.0" diameter pipe = 3.14159 * 2 * 2 = 12.5663 sq in
Remember now too that exhaust flows in pulses and not a continuous stream. The addition of both banks of 3" pipes does NOT mean you need to suddenly flow DOUBLE what 3" pipes flow. In effect you need to still only manage each pulse firing with consideration that you may have occasional double pulses passing through the collector (this is a result of still only one cylinder firing at a time but unequal length banks in your y-pipe.) A single pulse passing through a 7.0 sq in cross section into a 12.5sq in cross section will dramitaclly slow down and cool off as well (bad for velocity.)
A calculated dual 3" y into a 3.5" I and a cutout will net you the same power as the sytem you describe and will pass through your g load brace and wont bang your floorboard like the 4". In just about any instance i can think of the power you are making wiht your car does not justify 4" exhaust.
Some things to look at:
Flow capacity-
3.0" diameter pipe = 3.14159 * 1.5 * 1.5 = 7.0685 sq in
3.5" diameter pipe = 3.14159 * 1.75 * 1.75 = 9.6211 sq in
4.0" diameter pipe = 3.14159 * 2 * 2 = 12.5663 sq in
Remember now too that exhaust flows in pulses and not a continuous stream. The addition of both banks of 3" pipes does NOT mean you need to suddenly flow DOUBLE what 3" pipes flow. In effect you need to still only manage each pulse firing with consideration that you may have occasional double pulses passing through the collector (this is a result of still only one cylinder firing at a time but unequal length banks in your y-pipe.) A single pulse passing through a 7.0 sq in cross section into a 12.5sq in cross section will dramitaclly slow down and cool off as well (bad for velocity.)
A calculated dual 3" y into a 3.5" I and a cutout will net you the same power as the sytem you describe and will pass through your g load brace and wont bang your floorboard like the 4". In just about any instance i can think of the power you are making wiht your car does not justify 4" exhaust.
#97
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Originally Posted by Full-Force
OK, now let me build you one of my systems to get it to 500 ![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
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#98
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Originally Posted by Full-Force
Instead of pulling out books and digging up info on the net to make it sound like you are an exhaust engineer how about just posting up some plain old fashioned results.