X or Y
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06-14-2006, 06:30 AM
#9
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Originally Posted by SLP4CamaroSS
so basically all the difference is the noise
The easy answer is both setups work and work well.
Things to consider are price, fitment, availability, clearance, flow, db reduction amoung others.
There is abolutly no reason why duals should be any louder than any other setup. People who tell you duals are always loud are simply talking out of their ****. Mustangs, Corvettes, V8 Jaguars all run duals as STOCK yet they are all pretty quiet, espcially the Jaguar.
The reason duals are often thought of as loud is many people dump them before the axle. This is due to space limitations mostly and ease of fitment. Such setups usually only have smaller mufflers which do not sugnificantly reduce db levels. Also having the exhaust exiting under the car makes the car body act very much like an acoustic guitar does and effectively amplify the sound, espcially in the cabin.
Plus side to duals:
-Flow rate. 2.5" duals will easily outflow a 3" Y pipe setup. And 3" duals are even better (don't get carried away here though, I'll explain in a bit).
-Sound, duals will sound different to a Y setup and in most cases sound better although this is personal. H pipes offer the deeper old school sound while the more popular X pipe setup seems to offer a more racey exotic sound.
Down sides to duals:
-Availability, there are not many off the shelf kits. TSP offer some but they dump before the axle and are made of mild steel. Most people with duals have to go for a custom set made for the car.
-Routing, if you dump before the axle then there's plenty of room. However getting past the axle to the back of the car is more difficult. The Fbody has a real lack of room. It can be done and has been by many people but expect it to cost more. Some people go over the axle and some under. Going under is certainly easier but it will reduce your ground clearance and may be problomatic when jacking the car due to axle droop. This may even occur when drving spritly on a bumpy road. Going over the axle has space limitations due to axle movement.
-Running a body mounted torque arm. This things are great for 1/4 mile action and will certainly improve ET's. However they attach to the car where most dual setups want to place the X pipe. This means the only way of fitting it is to have the body mounted TA already on the car and custom design the exhaust to fit around it. H pipe setups are likely to be easier to fit with a body mounted TA.
-Price. If you require a full custom dual setup out the back using stainless steel and mandrel bends it's going to cost. To get a like for like dual setup compared to a Y setup will cost you more money. It doesn't have to be expensive but it's worth calculating first.
Some info on Y pipes:
-first off lets dispell the myth that Y pipes don't scavenge because they do and with a good merge collector they will scavenge in very much the same manor as an X pipe.
-Flow rate, now although a 2.5" dual system will outflow a 3" Y setup that doesn't mean the Y setup is no good. In fact a 3" Y flows pretty good and will be very efficent on ALL bolt on/cam only cars and still only have minimal affect on full h/c cars. If you plan on a serious FI setup then you may want to reconsider a 3" Y setup although many people have seen well over 600rwhp running a regular 3" Y. 3.5" and even 4" Y setups are available, although some degree of custom work maybe required and fitting may be more problematic.
-Sound. It's true a Y setup will sound different but that doesn't mean it will sound bad. In fact there are many great sounding Y setups out there. Also a Y setup can be just as loud or quiet as any dual setup.
-Availability and fitment. There are literally hundreds of off the shelf catbacks to choose from, this means that fitment and price are very competative. You can get a new catback from about $200 and stainless ones for $400 and on the whole they all bolt up easily using existing hangers/brackets.
For more proof that Y setups work well here's some info from LG, they make arguably the best headers for Corvettes. They actually convert their own X pipe into a Y pipe for race use:
Originally Posted by LG Motorsports
When we used a hand built Merge collector they cost us $450 each. that made the original headers cost $2500 per set without cats.
When we made the deal with Borla we specified a production, machine made collector to get the price of the complete set of headers down but we did not want to compromise the quality or power of our headers.
When we got our first set of prototype headers, we switched back and forth from the Production Merge collector to the Hand built collector and there was less than 2 hp difference. That is why we chose to supply the collector the way we do.
The alternative was to cheap out and use a plain stamped collector that had no relationship to a Merge collector. Or do what we did. We know from dyno testing that the Merge collector built the way we have them built causes a "venturi" effect where the collector necks down to 2 1/2" before the tapered transition up to the 3" out let. It is this "Merge down and Transition up at a specific angle that provides the effect that has come to be known as a "Merge" Collector.
The cone in the center is only 1 or 2 hp and since the full Merge collector that we use provided most of the gains without it, we chose to leave it and the other $900 out of the equation.
Again, the results speak for themself. We use our LG Pro Long Tube headers in our World Challenge race car exactly the way you get them for your street car. The only difference is that we turn the X pipe into a Y pipe and exit the exhaust out the side of the car, over the passenger floor and through the right side frame rail and rocker pannel.
Our headers run down the straight equal to the fastest Cadillac CTSv and every fast Corvette runs our LG headers.
We could get a couple more hp if we did some extensive exhaust testing on Merge angles in and cone angles out but the cost is prohibitive.
Thanks
Lou Gigliotti LGM
When we made the deal with Borla we specified a production, machine made collector to get the price of the complete set of headers down but we did not want to compromise the quality or power of our headers.
When we got our first set of prototype headers, we switched back and forth from the Production Merge collector to the Hand built collector and there was less than 2 hp difference. That is why we chose to supply the collector the way we do.
The alternative was to cheap out and use a plain stamped collector that had no relationship to a Merge collector. Or do what we did. We know from dyno testing that the Merge collector built the way we have them built causes a "venturi" effect where the collector necks down to 2 1/2" before the tapered transition up to the 3" out let. It is this "Merge down and Transition up at a specific angle that provides the effect that has come to be known as a "Merge" Collector.
The cone in the center is only 1 or 2 hp and since the full Merge collector that we use provided most of the gains without it, we chose to leave it and the other $900 out of the equation.
Again, the results speak for themself. We use our LG Pro Long Tube headers in our World Challenge race car exactly the way you get them for your street car. The only difference is that we turn the X pipe into a Y pipe and exit the exhaust out the side of the car, over the passenger floor and through the right side frame rail and rocker pannel.
Our headers run down the straight equal to the fastest Cadillac CTSv and every fast Corvette runs our LG headers.
We could get a couple more hp if we did some extensive exhaust testing on Merge angles in and cone angles out but the cost is prohibitive.
Thanks
Lou Gigliotti LGM
06-14-2006, 12:45 PM
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thanks 300bhp it just that when i get my headers i can either get a ypipe for 125 and change my lm for a different resonator or make a xpipe for about 200 just kind of trying to figure out what i want to do lol
