SPD_FRK
07-12-2009, 10:19 PM
Upper Intake Manifold
This is a very common upgrade for many of you out there. The "standard" option for upgrading these parts has been the Diamante, or another option is the XG350 manifold. The reason for this switch is due to the design of the stock intake manifold having "squished" intake runners. This design can affect how efficient the air flows into the combustion chamber, as well as how much air is taken in. Also between the two manifold options they can increase better mid-range-high end response/performance.
Early Model Diamante Upper Manifold
Below shows pictures of the stock Galant upper intake manifold side by side with the Diamante manifold. You will see the obvious difference is the intake runners between the two. Also the other clear difference is the size of the air inlet section of the manifold before it goes into the runners. The throttle body mounting plate is also a different size (bore is larger on Diamante than the stock unit).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0526090748-00.jpg
The differences with swapping from the stock manifold are fairly limited and "minor." When you look at a stock manifold side by side with the Diamante manifold you will clearly see how the stock intake runners are "squished" and the size of the manifold where the throttle body bolts to is smaller.The stock MAP Sensor will fit onto the Diamante manifold, but you will have to fabricate a longer EGR tube to run from the rear exhaust manifold to the upper intake manifold. This is something that can be "blocked" if the build requires that route, but for the majority of people who need to pass emissions it is in your best interest to have a piece fabricated.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0608091247-00.jpg
The manifold is also going to set your throttle body off more to the driver's side of the engine bay due to the straightened intake runners. This is only a minor issue and you should be able to fabricate the correct intake piping for the bend needed. For some, depending on the specific build you may need to relocate the battery from the stock location.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0526090749-00.jpg
The Diamante Upper Intake manifold has an inlet size of about 69mm, with the potential to safely increase the bore 3-4mm. The stock manfiold has an inlet size of only 60mm.
Late Model Diamante Manifold
Item to be purchased and specs published shortly
XG350 Variable Intake Manifold
This is another manifold option for those who want to make the swap. In my eyes, and even in your own (as you can see in the photos), this is the "best" choice for a manifold upgrade. The throttle body inlet size is the same as the Diamante unit (roughly 69mm). With the 3 piece type design of this manifold it is a better option for those seeking to build even more performance of the 6G72/6G74 platforms. If you are building a heavily modified N/A engine, or a boosted engine, the manifold can be seperated and a custom intake plenum assembly fabricated to fit the runners section. Doing this type of fabrication is generally needed for those running a larger throttle body such as one from the Infinity Q45 which is a stock 90mm unit (largest production TB made).
Below pictures the XG350 manifold side by side with the early model Diamante manifold. You will notice a sizeable difference between the two in the plenum areas. Also note that the MAP sensor locations are on opposite sides of the manifold as well. The EGR mounting location is about the same, but the EGR valve from the Diamante (or stock manifold too), cannot be used on the XG350 as you will see in the photo they are different. The XG350 actually uses a EGR valve that has the exhaust gas pipe running directly into the EGR valve (which makes it easy to fabricate a piece for those with emissions).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091947-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091935-00.jpg
The Diamante manifold has a plenum diameter of roughly 91mm (3 9/16"), whereas the XG350 manifold has a diameter of roughly 125mm (4 7/8").
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091951-01.jpg
There is additional volume in the XG350 plenum as you can see in the photos of the Middle section of the manifold. Note, I have removed the valves within this section as these are not needed for my specific build. This is something I do want to look into further to make it fully functional for others who could benefit from the functionality in the entire range of this manifold's intended design. The XG350 uses a sensor/motor control on the valves to regulate the amount of air that flows through the manifold assembly and into the combustion chamber. The primary section utilizes the smaller runner diameter internally to help increase the low end-mid range torque. With the higher RPMs the sensor/motor will open the secondary valves to allow an increased amount of air flow that assists with increased torque in the mid range-high end.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091625-00.jpg
This photo shows you the material that can be removed to combine the primary and secondary runner ports into one large runner section out of the plenum
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091626-00.jpg
Looking into the center section, with the rear part of the plenum attached you can see the plastic dividers inside that feed the primary runners when the valves are closed up. When the valves are opened the majority of the incoming air flow will enter through the larger ports of this section.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091623-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091622-00.jpg
Here the rear part of the plenum is removed and shows you the plastic runner inserts mounted, and then with them removed for applications such as mine where they are not needed;
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0711091405-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0711091405-01.jpg
Intake runner length also has an affect on performance as well. Below shows the runner length (within 1/4") difference between the Diamante manifold, and the XG350 manifold. The Diamanter manifold (first photo below) has a length of roughly 12" to from the lower manifold mounting surface to the edge of the plenum. The XG350 manifold has a length of approximately 10" from the same locations (in this case to where the middle section bolts to the runner section).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091957-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091955-00.jpg
Throttle Body
Now before you jump into purchasing these items it is important to know the details of the upgrade, and there are some differences you need to know about. The stock throttle body has an internal diameter of 65mm whereas the Diamante is 68mm. There is obviously only a 3mm difference in size here, so you have to wonder if the upgrade is worth the extra 3mm. Also, the Diamante throttle body is sometimes labeled as a "Bigger Bore" throttle body upgrade. This is in a sense true as it is larger than stock, however not one to be considered a true Big Bore Throttle Body. The majority of big bore throttle bodies will step the internal diameter up anywhere from 5-10mm, or more depending on the requirements of the engine. For the time being, the Diamante throttle body is a reasonable upgrade given the current aftermarket options available (which could very well change in the future).
Another issue with the Diamante throttle body is that the sensors (TPS and IAC) on older units are different from the OEM sensors. The newer Diamante throttle body sensors are the same size, and pin number as the stock ones, so you would want to find a throttle body from a 1999 or newer Diamante. The difference between the older (likely pre-1999) Diamante IAC and TPS sensors and those on the 1999-2003 Galants differ as shown in the photos below. The IAC plugs have the same number of pins (6), but the plug size is completely different;
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090746-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090752-00.jpg
The TPS Sensors are also different from the older units as 1999-Newer used a 3 pin sensor, whereas prior to 1999 they used a 4 pin sensor. The other issue with the TPS sensor pertains to those with cruise control. If you do not have cruise control on your model then try to find a throttle body without cruise control. If you are unable to find one without cruise control you can modify the throttle body to eliminate these components (will be added soon). Those of you out there who do have cruise control will notice the TPS Sensors are different how they are activated with the opening/closing of the butterfly plate. The pictures below will show you the differences from a stock unit with cruise control and the Diamante (stock unit on left).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090743-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090744-00.jpg
As current options are limited for a larger bore throttle body at this time, the increased size of 3mm is minimal and hardly worth the cost. With any one of the options for upper intake manifold out there, combined with a stock throttle body the improvements will be justified in just the manifold swap. There is another option for a larger (70mm+) throttle body, but it will require some farbication and really only suited for those with heavy engine modifications. As this information is gathered I will update this section of the posting.
**This is a work in progress. More pictures and information will be added
This is a very common upgrade for many of you out there. The "standard" option for upgrading these parts has been the Diamante, or another option is the XG350 manifold. The reason for this switch is due to the design of the stock intake manifold having "squished" intake runners. This design can affect how efficient the air flows into the combustion chamber, as well as how much air is taken in. Also between the two manifold options they can increase better mid-range-high end response/performance.
Early Model Diamante Upper Manifold
Below shows pictures of the stock Galant upper intake manifold side by side with the Diamante manifold. You will see the obvious difference is the intake runners between the two. Also the other clear difference is the size of the air inlet section of the manifold before it goes into the runners. The throttle body mounting plate is also a different size (bore is larger on Diamante than the stock unit).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0526090748-00.jpg
The differences with swapping from the stock manifold are fairly limited and "minor." When you look at a stock manifold side by side with the Diamante manifold you will clearly see how the stock intake runners are "squished" and the size of the manifold where the throttle body bolts to is smaller.The stock MAP Sensor will fit onto the Diamante manifold, but you will have to fabricate a longer EGR tube to run from the rear exhaust manifold to the upper intake manifold. This is something that can be "blocked" if the build requires that route, but for the majority of people who need to pass emissions it is in your best interest to have a piece fabricated.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0608091247-00.jpg
The manifold is also going to set your throttle body off more to the driver's side of the engine bay due to the straightened intake runners. This is only a minor issue and you should be able to fabricate the correct intake piping for the bend needed. For some, depending on the specific build you may need to relocate the battery from the stock location.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0526090749-00.jpg
The Diamante Upper Intake manifold has an inlet size of about 69mm, with the potential to safely increase the bore 3-4mm. The stock manfiold has an inlet size of only 60mm.
Late Model Diamante Manifold
Item to be purchased and specs published shortly
XG350 Variable Intake Manifold
This is another manifold option for those who want to make the swap. In my eyes, and even in your own (as you can see in the photos), this is the "best" choice for a manifold upgrade. The throttle body inlet size is the same as the Diamante unit (roughly 69mm). With the 3 piece type design of this manifold it is a better option for those seeking to build even more performance of the 6G72/6G74 platforms. If you are building a heavily modified N/A engine, or a boosted engine, the manifold can be seperated and a custom intake plenum assembly fabricated to fit the runners section. Doing this type of fabrication is generally needed for those running a larger throttle body such as one from the Infinity Q45 which is a stock 90mm unit (largest production TB made).
Below pictures the XG350 manifold side by side with the early model Diamante manifold. You will notice a sizeable difference between the two in the plenum areas. Also note that the MAP sensor locations are on opposite sides of the manifold as well. The EGR mounting location is about the same, but the EGR valve from the Diamante (or stock manifold too), cannot be used on the XG350 as you will see in the photo they are different. The XG350 actually uses a EGR valve that has the exhaust gas pipe running directly into the EGR valve (which makes it easy to fabricate a piece for those with emissions).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091947-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091935-00.jpg
The Diamante manifold has a plenum diameter of roughly 91mm (3 9/16"), whereas the XG350 manifold has a diameter of roughly 125mm (4 7/8").
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091951-01.jpg
There is additional volume in the XG350 plenum as you can see in the photos of the Middle section of the manifold. Note, I have removed the valves within this section as these are not needed for my specific build. This is something I do want to look into further to make it fully functional for others who could benefit from the functionality in the entire range of this manifold's intended design. The XG350 uses a sensor/motor control on the valves to regulate the amount of air that flows through the manifold assembly and into the combustion chamber. The primary section utilizes the smaller runner diameter internally to help increase the low end-mid range torque. With the higher RPMs the sensor/motor will open the secondary valves to allow an increased amount of air flow that assists with increased torque in the mid range-high end.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091625-00.jpg
This photo shows you the material that can be removed to combine the primary and secondary runner ports into one large runner section out of the plenum
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091626-00.jpg
Looking into the center section, with the rear part of the plenum attached you can see the plastic dividers inside that feed the primary runners when the valves are closed up. When the valves are opened the majority of the incoming air flow will enter through the larger ports of this section.
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091623-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091622-00.jpg
Here the rear part of the plenum is removed and shows you the plastic runner inserts mounted, and then with them removed for applications such as mine where they are not needed;
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0711091405-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0711091405-01.jpg
Intake runner length also has an affect on performance as well. Below shows the runner length (within 1/4") difference between the Diamante manifold, and the XG350 manifold. The Diamanter manifold (first photo below) has a length of roughly 12" to from the lower manifold mounting surface to the edge of the plenum. The XG350 manifold has a length of approximately 10" from the same locations (in this case to where the middle section bolts to the runner section).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091957-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0712091955-00.jpg
Throttle Body
Now before you jump into purchasing these items it is important to know the details of the upgrade, and there are some differences you need to know about. The stock throttle body has an internal diameter of 65mm whereas the Diamante is 68mm. There is obviously only a 3mm difference in size here, so you have to wonder if the upgrade is worth the extra 3mm. Also, the Diamante throttle body is sometimes labeled as a "Bigger Bore" throttle body upgrade. This is in a sense true as it is larger than stock, however not one to be considered a true Big Bore Throttle Body. The majority of big bore throttle bodies will step the internal diameter up anywhere from 5-10mm, or more depending on the requirements of the engine. For the time being, the Diamante throttle body is a reasonable upgrade given the current aftermarket options available (which could very well change in the future).
Another issue with the Diamante throttle body is that the sensors (TPS and IAC) on older units are different from the OEM sensors. The newer Diamante throttle body sensors are the same size, and pin number as the stock ones, so you would want to find a throttle body from a 1999 or newer Diamante. The difference between the older (likely pre-1999) Diamante IAC and TPS sensors and those on the 1999-2003 Galants differ as shown in the photos below. The IAC plugs have the same number of pins (6), but the plug size is completely different;
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090746-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090752-00.jpg
The TPS Sensors are also different from the older units as 1999-Newer used a 3 pin sensor, whereas prior to 1999 they used a 4 pin sensor. The other issue with the TPS sensor pertains to those with cruise control. If you do not have cruise control on your model then try to find a throttle body without cruise control. If you are unable to find one without cruise control you can modify the throttle body to eliminate these components (will be added soon). Those of you out there who do have cruise control will notice the TPS Sensors are different how they are activated with the opening/closing of the butterfly plate. The pictures below will show you the differences from a stock unit with cruise control and the Diamante (stock unit on left).
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090743-00.jpg
http://i228.photobucket.com/albums/ee207/HD-SPDFRK/Galant/0520090744-00.jpg
As current options are limited for a larger bore throttle body at this time, the increased size of 3mm is minimal and hardly worth the cost. With any one of the options for upper intake manifold out there, combined with a stock throttle body the improvements will be justified in just the manifold swap. There is another option for a larger (70mm+) throttle body, but it will require some farbication and really only suited for those with heavy engine modifications. As this information is gathered I will update this section of the posting.
**This is a work in progress. More pictures and information will be added