INSTALLING AN (X) PIPE IN THE EXHAUST ON A DUAL EXHAUST CAR
READ THRU ALL THE SUB LINKED INFO IN THIS THREAD ALSO
viewtopic.php?f=56&t=185&p=219#p219
buy this TOOL and custom fit the (X) INTO YOUR EXHAUST SYSTEM youll want to use a decent welder but its fast and a no-brainer AS LONG AS YOU REMEMBER TO CAREFULLY MEASURE BOTH THE (X) AND THE PROPOSED OPENING TO BE CUT,BEFORE CUTTING AND HAVE THE (X) BE A BIT LONGER THAN THE OPENING BETWEEN THE OLD PIPE WHERE ITS INSTALLED FOR AN OVERLAP NOT A BUTT WELD
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?function=Search
ITEM 37354-9VGA
$10.99 YOU CAN,T AFFORD NOT TO HAVE THIS TOOL IF YOU DO EXHAUST PIPE MODS, PERSONALLY I LIKE AN OXY-ACETOLENE TORCH FOR THIS TYPE WELD BUT ALMOST ANY WELDER WILL WORK, this is one area those little 110 volt migs are great for!
http://www.autoanything.com/exhausts-mufflers/69A2672A0A0.aspx
http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE-10792&N=700+115&autoview=sku
http://store.summitracing.com/partdetail.asp?autofilter=1&part=HED-18830&N=700+115&autoview=sku
WHY INSTALL AN (X)???
The lower your restriction to exhaust flow the better, past the headers collectors
An (X) basically allows BOTH sides of your exhaust system to share and split the exhaust flow, a 3†pipe has approximately a 7 sq inch cross section, splitting the flow doubles the area and tends to reduce the back pressure a good deal as your now using 14 sq inches vs 7†to allow the gases to both expand and cool, remember as hot exhaust gases cool the volume shrinks, and an added benefit is a mellower exhaust tone.
yes I strongly advise upgrading a corvettes exhaust on a performance build to 3" from the header collectors and back!most guys I talk and deal with,seem to think that slapping a set of headers on thier car is all thats required to boost performance....ANY HEADERS! ...and they fail to realize that both the header design and the exhaust system behind them require a good deal of thought if you want the maximum benefits, and that simply hooking a restrictive exhaust system to the collectors on the best headers will negate most of thier potential benefits.
most commercial headers are designed mostly for ease of manufacturing and ease of installation,little thought goes into maximizing the cylinder scavaging which is thier main function.
your fooling yourself if you think headers will provide a big boost in hp/tq without the low restriction exhaust behind them,and in most cases that requires a larger dia. exhaust system and adding an (X) to the system and extending the header collectors at thier full dia. up till at least the exit of the (X) so the twin exhaust pipes cross sectional area can provide that reduced restriction to flow, rather than the reducers many guys install to the collector exits to adapt them to the stock exhaust system
example of a well laid out exhaust (MELROSE)
but even that system could be hurt if you slap restrictive mufflers on it
bjhines posted these and thier good examples
looking thru an (X) pipe
mocking it up
X Versus H
It's long been known that connecting the two sides of a dual exhaust system, shortly after the headers, increases power and reduces sound. However in a traditional "H" pipe, only sound and pressure waves cross through the connection. Gasses take the route of lowest pressure, which is straight out the pipe, rather than making a 90 degree turn in to the H.
Indy and Nascar teams have been using "X" type crossovers for quite some time. In an "X" pipe the gasses from both cylinder banks actually pass through a common area. This not only provides the benefits of some sound wave cancellation, but also increases the scavenging effect, helping draw out spent charge from the combustion chamber.
So how much of an increase does an X gain over an H? It's hard to say, especially considering that every combination will yield varying gains. In theory an X will work better as rpms go up. Considering the Flowtech X-Terminator pieces are priced under $50; you're much better off getting that, rather than having a shop fab up a crude 'H' piece.
viewtopic.php?f=56&t=1503
READ THRU ALL THE SUB LINKED INFO IN THIS THREAD ALSO
viewtopic.php?f=56&t=185&p=219#p219
buy this TOOL and custom fit the (X) INTO YOUR EXHAUST SYSTEM youll want to use a decent welder but its fast and a no-brainer AS LONG AS YOU REMEMBER TO CAREFULLY MEASURE BOTH THE (X) AND THE PROPOSED OPENING TO BE CUT,BEFORE CUTTING AND HAVE THE (X) BE A BIT LONGER THAN THE OPENING BETWEEN THE OLD PIPE WHERE ITS INSTALLED FOR AN OVERLAP NOT A BUTT WELD
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?function=Search
ITEM 37354-9VGA
$10.99 YOU CAN,T AFFORD NOT TO HAVE THIS TOOL IF YOU DO EXHAUST PIPE MODS, PERSONALLY I LIKE AN OXY-ACETOLENE TORCH FOR THIS TYPE WELD BUT ALMOST ANY WELDER WILL WORK, this is one area those little 110 volt migs are great for!
http://www.autoanything.com/exhausts-mufflers/69A2672A0A0.aspx
http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE-10792&N=700+115&autoview=sku
http://store.summitracing.com/partdetail.asp?autofilter=1&part=HED-18830&N=700+115&autoview=sku
WHY INSTALL AN (X)???
The lower your restriction to exhaust flow the better, past the headers collectors
An (X) basically allows BOTH sides of your exhaust system to share and split the exhaust flow, a 3†pipe has approximately a 7 sq inch cross section, splitting the flow doubles the area and tends to reduce the back pressure a good deal as your now using 14 sq inches vs 7†to allow the gases to both expand and cool, remember as hot exhaust gases cool the volume shrinks, and an added benefit is a mellower exhaust tone.
yes I strongly advise upgrading a corvettes exhaust on a performance build to 3" from the header collectors and back!most guys I talk and deal with,seem to think that slapping a set of headers on thier car is all thats required to boost performance....ANY HEADERS! ...and they fail to realize that both the header design and the exhaust system behind them require a good deal of thought if you want the maximum benefits, and that simply hooking a restrictive exhaust system to the collectors on the best headers will negate most of thier potential benefits.
most commercial headers are designed mostly for ease of manufacturing and ease of installation,little thought goes into maximizing the cylinder scavaging which is thier main function.
your fooling yourself if you think headers will provide a big boost in hp/tq without the low restriction exhaust behind them,and in most cases that requires a larger dia. exhaust system and adding an (X) to the system and extending the header collectors at thier full dia. up till at least the exit of the (X) so the twin exhaust pipes cross sectional area can provide that reduced restriction to flow, rather than the reducers many guys install to the collector exits to adapt them to the stock exhaust system
example of a well laid out exhaust (MELROSE)
but even that system could be hurt if you slap restrictive mufflers on it
bjhines posted these and thier good examples
looking thru an (X) pipe
mocking it up
X Versus H
It's long been known that connecting the two sides of a dual exhaust system, shortly after the headers, increases power and reduces sound. However in a traditional "H" pipe, only sound and pressure waves cross through the connection. Gasses take the route of lowest pressure, which is straight out the pipe, rather than making a 90 degree turn in to the H.
Indy and Nascar teams have been using "X" type crossovers for quite some time. In an "X" pipe the gasses from both cylinder banks actually pass through a common area. This not only provides the benefits of some sound wave cancellation, but also increases the scavenging effect, helping draw out spent charge from the combustion chamber.
So how much of an increase does an X gain over an H? It's hard to say, especially considering that every combination will yield varying gains. In theory an X will work better as rpms go up. Considering the Flowtech X-Terminator pieces are priced under $50; you're much better off getting that, rather than having a shop fab up a crude 'H' piece.
viewtopic.php?f=56&t=1503