Magnum Powers Upgraded '94/95 Inlet Plenum

Typical gains are 20 to 30 HP over the stock inlet plenum, when combined with a 85mm Tbody. Fatten up your torque curve and enjoy the power from the MP High Flow Plenum!

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SCP will attempt to meet or beat any other sources pricing on an identical item. Call us to discuss 513-697-6501.

Note: This is an older item that has been superseded by the MPx supercharger and its inlet plenum. Please call to inquire about availability and delivery timing.


This plenum is only for the rectangular rear inlet supercharger produced in '94/95. This plenum will also work on our "S" Model superchargers and the Magnum Powers MPII supercharger cases which were a upgraded '94/95 case.


Typical gains are 20 to 30 HP over the stock inlet plenum, when combined with a 85mm Tbody. Fatten up your torque curve and enjoy the power from the MP High Flow Plenum!


If your car has EGR, then you will need one of the EGR adapters which can be found on the "Related Items" link on this page.


Gray powder coated finish is standard.


Magnum Powers Inlet Review:

From The September 2000 SCCoA Chargin' Thunder Newsletter

It isn’t very often a completely new Super Coupe engine performance part is developed. A careful Chargin’ Thunder reader should have noticed that a new part did debut in the last issue in a Super Coupe Performance (SCP) advertisement. If you were as curious about the Magnum Powers inlet as I was, I’ll bet you were wondering "what can that humongous inlet do for me?" just like I was. Today, you will get your answer!

Being the speed crazed…err, I mean "scientifically" minded person that I am, I felt a test was in order to judge the effectiveness of this new inlet on a car equipped with the SCP 340 HP kit. Coy Miller has already dyno tested this inlet on several of his engines with terrific results and he has adopted it across the board as the inlet of choice for his extreme output monsters. The question is, "It’s great for Coy, but will it help my little old motor with stock heads and bolt-on parts"?


I decided to spend some money on a dyno test of the inlet. Now you can understand why I did not wish to dyno all three supercharger tops in addition to this inlet. At $100 per dyno session, I’d go broke! I had previously tested my car at the Carlisle dyno, but that was two years ago. I felt that to have a truly fair test I must get a new baseline. I went to Paul’s Automotive Engineering in Cincinnati, Ohio, for the tests. As an aside, Paul’s is a well known restoration and performance shop specializing in Mustangs. Paul himself treated me to a tour of the shop after my baseline run. This facility is capable of doing anything you desire as long as your budget can stand the punishment. Paul commented that a typical concourse Shelby restoration costs over $100K and will take one to two years to complete. They also perform a lot of supercharger installations on late model Cobras and set up many customer cars for road racing. This is one serious place for anyone looking for uncompromising work on his or her Mustang!


Thankfully, my new baseline was very comparable to the previous one at Carlisle. I did improve slightly on both rear wheel horsepower and torque with readings of 270 HP and 353 T vs. 263 HP and 345 T previously. Paul and the other dyno operators were dutifully surprised with my lil’ old 3.8L V6. They said it far exceeded what many modified 5.0L engines put out. The tremendously fat torque curve especially impressed them.


The installation of the Magnum Powers inlet went very smoothly. It was a direct bolt up and had all the factory drilled and tapped holes in all the proper places. My 5-speed SC has EGR, which complicated things a bit when it came time to hook that up. I had the pleasure of being the guinea pig with regards to being the first person to utilize EGR with one of these plenums. The prototype EGR adapter I was provided worked with a bit of persuasion but proved to be a bit of a pain as are all EGR related issues on the SC engine. This adapter is now being made on a production basis, so I’m sure it will have a factory fit on all future inlets that may require it.


I also had the pleasure of using the one and only Magnum Powers 83mm throttle body in existence. This Big Dog required the use of a special inlet tube to hook up to my mass air meter. This proved to be an easy hookup and looked extremely impressive to boot. With everything in place, I headed back to Paul’s for another set of dyno pulls to see what my new numbers were. I was able to drive the car for a few days prior to the testing and the seat of the pant’s feel was positive. The boost came on very hard and engine seemed quicker to spool up. The sound from the huge inlet system was also quite a wail. I could really hear the "S" model whistling away upon full throttle. I asked for the same dyno operator at Pauls and also went on a day with nearly identical weather conditions for my second set of pulls. I wanted to minimize any variables between the "before" and "after" pulls. Note that no other components were changed on my car. I even used a 73mm C&L mass air unit, which looked plum small, compared to the monster MP 83mm throttle body.


The Results:

Let’s get straight to the point! The engine was substantially improved in virtually every aspect as can be seen on the chart on the next page. Peak output improved over 17 Rear Wheel HP at 100 RPM higher in the curve. Peak rear wheel torque was up nearly 15 at 200 RPM lower. Therefore, the usable engine RPM power band has been expanded!


Peak values don’t always tell the whole story though. Check out the torque curve. Improvements in torque are almost immediate and start with a 13 to 14 ft-lb advantage as low as 2400 RPM. So much for the idea that putting too large an intake on these motors will cause a loss of low RPM torque. That myth has been disproved! Torque keeps improving with rpm and around 4600 RPM and above the actual difference is between a 20 to 22 ft-lb improvement.


Take a good look at the horsepower curve also. I have already mentioned the 17-peak RWHP improvement, but look at the way the original curve starts to die around 4800 RPM. The Magnum Powers components have extended the useable power band and horsepower improvements over 4800 RPM actually are in the range 20 to 23 RWHP.


Wonder no more, my fellow forced induction friends. The Magnum Powers components have been scrutinized and tested with all the data laid out before you. These parts work like a dream and bolt in place with ease. Give them a try and feel the Magnum Power…or should that be Magnum Powers!