Justin@VMP
July 1st, 2008, 09:21 AM
The 05+ Mustang 4.6L 3V Intercooled Roush M90 supercharger kit re-uses the factory intake.
We already know this piece is very restrictive, even on a stock car, we see a gain of 10-15HP from replacing it with a higher flowing CAI kit.
The factory intake is even more restrictive on the Rouscharged cars, even though they replace the paper filter with a K&N, the factory 80MM MAF housing and lid design restricts flow.
Replacing the intake with a higher flowing piece results in a gain of ~30 Crank HP (25RWHP), see Run 2 vs Run 9 below. The removal of the intake restriction results in a slight increase in boost. Tuning is required at this point, because the location and airflow over the MAF sensor changes.
http://www.vmptuning.com/dynographs/redautoroushfinal.jpg
If you want more power the next step is to swap on a smaller supercharger pulley. VMP produces a one piece steel 2.57" upper pulley and 90mm idler. The idler pulley takes up the slack in the belt and improves wrap around the pulley, the stock belt is re-used. The pulley results in a 2-3psi boost increase and another increase of ~40 Crank HP (30RWHP) See Run 12 above.
Installing the CAI:
Remove the factory airbox, you'll need a 10mm socket to unscrew the bolt next to the fender. Use an 8mm nut driver or flathead to loosen both clamps on the black hump hose.
Pull the stock airbox out, there are two rubber grommets on the bottom, keep them installed in the stock location below the factory airbox.
Remove the plastic Roush tube that goes in front of the engine, you'll need to unscrew the two 8mm bolts holding the tube down, and loosen both clamps at the throttle body. There is also a PCV line that will need to be disconnected, find the green tab on it and push down on the tab while pulling the hose off the tube.The factory MAF sensor is installed in the Roush tube, you will need to remove it (allen wrenches required) and install it into the new CAI.
http://vmptuning.com/pics/1RSCstockmaf.jpg
You will need to take the blocker plate off the stock intake (T20 torx bit required) and install it onto the bottom of the Roush tube using the allen screws that were holding the MAF sensor.
http://vmptuning.com/pics/2newblockoff.jpg
You can now install the stock MAF sensor into the new CAI, using the included M4 x .5 machine screws.
http://www.vmptuning.com/store/images/products/s90rsc.jpg
The black silicone hump hose is re-used, but will have to be stretched to fit the new intake. I like to put it over the jaws of a vice, while pressing it onto the jaws and opening them at the same time, then turn 90* and repeated. Then I can fit it onto the intake with a little effort. You will also need a larger clamp, the stock Roush size 52 clamp is too small, a size 60 clamp will work.
Installing the smaller blower pulley and idler:
You will need an impact gun to take the nut off the supercharger. The black Roush intake tube will have to be removed to access the pulley.
The stock Roush pulley may slide right off, or it may need a little bit of force on it. If it does not slight right off you can use a standard automotive 2 or 3 jaw puller from the autoparts store to help it along. The Roush pulleys are NOT press fit like Cobras and Lightnings, so a special puller is not required.
The VMP 2.57" pulley should slide right onto the keyed shaft, make sure the key did not fall out. Use a little bit of locktite on the threads and re-install the nut, using an impact gun to tighten it.
The VMP pulley kit includes a 90mm idler, to replace the factory idler and take up the slack in the belt. Remove the factory idler below the blower and install the VMP 90mm idler.
The smaller pulley requires a tune and also requires a CAI. If the boost is increased without replacing the intake and putting the MAF in a larger housing, the MAF sensor will peg.
Click Here for VMP's Roush Power Packages (http://www.vmptuning.com/store/index.php?p=catalog&parent=97&pg=1)
We already know this piece is very restrictive, even on a stock car, we see a gain of 10-15HP from replacing it with a higher flowing CAI kit.
The factory intake is even more restrictive on the Rouscharged cars, even though they replace the paper filter with a K&N, the factory 80MM MAF housing and lid design restricts flow.
Replacing the intake with a higher flowing piece results in a gain of ~30 Crank HP (25RWHP), see Run 2 vs Run 9 below. The removal of the intake restriction results in a slight increase in boost. Tuning is required at this point, because the location and airflow over the MAF sensor changes.
http://www.vmptuning.com/dynographs/redautoroushfinal.jpg
If you want more power the next step is to swap on a smaller supercharger pulley. VMP produces a one piece steel 2.57" upper pulley and 90mm idler. The idler pulley takes up the slack in the belt and improves wrap around the pulley, the stock belt is re-used. The pulley results in a 2-3psi boost increase and another increase of ~40 Crank HP (30RWHP) See Run 12 above.
Installing the CAI:
Remove the factory airbox, you'll need a 10mm socket to unscrew the bolt next to the fender. Use an 8mm nut driver or flathead to loosen both clamps on the black hump hose.
Pull the stock airbox out, there are two rubber grommets on the bottom, keep them installed in the stock location below the factory airbox.
Remove the plastic Roush tube that goes in front of the engine, you'll need to unscrew the two 8mm bolts holding the tube down, and loosen both clamps at the throttle body. There is also a PCV line that will need to be disconnected, find the green tab on it and push down on the tab while pulling the hose off the tube.The factory MAF sensor is installed in the Roush tube, you will need to remove it (allen wrenches required) and install it into the new CAI.
http://vmptuning.com/pics/1RSCstockmaf.jpg
You will need to take the blocker plate off the stock intake (T20 torx bit required) and install it onto the bottom of the Roush tube using the allen screws that were holding the MAF sensor.
http://vmptuning.com/pics/2newblockoff.jpg
You can now install the stock MAF sensor into the new CAI, using the included M4 x .5 machine screws.
http://www.vmptuning.com/store/images/products/s90rsc.jpg
The black silicone hump hose is re-used, but will have to be stretched to fit the new intake. I like to put it over the jaws of a vice, while pressing it onto the jaws and opening them at the same time, then turn 90* and repeated. Then I can fit it onto the intake with a little effort. You will also need a larger clamp, the stock Roush size 52 clamp is too small, a size 60 clamp will work.
Installing the smaller blower pulley and idler:
You will need an impact gun to take the nut off the supercharger. The black Roush intake tube will have to be removed to access the pulley.
The stock Roush pulley may slide right off, or it may need a little bit of force on it. If it does not slight right off you can use a standard automotive 2 or 3 jaw puller from the autoparts store to help it along. The Roush pulleys are NOT press fit like Cobras and Lightnings, so a special puller is not required.
The VMP 2.57" pulley should slide right onto the keyed shaft, make sure the key did not fall out. Use a little bit of locktite on the threads and re-install the nut, using an impact gun to tighten it.
The VMP pulley kit includes a 90mm idler, to replace the factory idler and take up the slack in the belt. Remove the factory idler below the blower and install the VMP 90mm idler.
The smaller pulley requires a tune and also requires a CAI. If the boost is increased without replacing the intake and putting the MAF in a larger housing, the MAF sensor will peg.
Click Here for VMP's Roush Power Packages (http://www.vmptuning.com/store/index.php?p=catalog&parent=97&pg=1)