How to make a 1991-94 Mercury Capri Faster & More MPG

Example of just changing the Air Filter from stock to non-stock
Example of just changing the Air Filter from stock to non-stock
Example of also using a larger J-pipe (behind radiator)
Example of also using a larger J-pipe (behind radiator)
This is a stock setup for a Capri.
This is a stock setup for a Capri.

Owners of a 1991-94 Mercury Capri (as well as many, many other cars) can easily and within an hour or two, convert their car's indirect air intake systems into a more direct air intake system. Most cars and truck use an indirect type system primarily to reduce noise and involved enclosed air boxes with the filter, narrow diameter pipes to constrict air flow and bends in the pipe to slow the air flow. It is a trade-off for performance and gas mileage. By changing the system to a more direct air intake, you will increase the horsepower from 2-6 mph and up to 3 MPG.

To convert your Capri, do the following:

1. Disconnect and remove the Coil.

2. Disconnect the ground wire near the Coil.

3. Loosen and remove the rubber Air Duct from the Volume Air Flow (VAF) Sensor. Disconnect any wiring attached to it.

4. Remove the retaining bolts of the Air Cleaner cover.

5. Remove the VAF and Air Cleaner cover (they are attached).

6. Remove the Air Filter and bottom section of the Air Cleaner cover. 

7. To separate the VAF from the Air Cleaner cover, remove the four bolts from inside the cover.  The Air Cleaner\bottom cover can be discarded.

You are ready to install a direct air flow by doing the following:

1. Attached a purchased MAF adapter to the VAF. Use a 3-inch diameter and center the VAF intake area within the diameter. The adapter costs $10-12.

2. Attached a suitable air intake pipe with a similar diameter with a rubber coupler and metal bands to secure it to the VAF adapter. Note: You have two options. One is to attached the pipe so that one end is near the transmission area, or, simply attach your Air Filter to the VAF adapter. For the latter, space is limited, not more than six inches long, at best. 

3. If you chose to attach the Air Filter to the VAF, you need to find a suitable place to fasten the coil and reattach the ground wire. Then you are done.

4. If you used a pipe, attach your Air Filter to the free end and fasten. Note: Do not use a filter that is larger than 6.5 x 6.5 inches. Find a place to fasten the coil and ground. You are done.

If you have a XR2 turbo model, the air duct will turn and bend to connect to it via a J-pipe. The black pipe is plastic and goes from 2.5" down to 1.5". If you elect to change the J-pipe that connects from the turbo to VAF, the diameter of the pipe cannot be greater than 2.5 inches.

This easy conversion costs anywhere from $30-100, depending on the materials and their quality. It takes not more than 1.5 hrs and you will notice greater horsepower (up to 7 mph) at certain RPMs and better gas mileage (2-4 mpg) in most cases. If some reason it is not to your expectation, simply reinstall the stock air cleaner.

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Comments 1 comment

brandon dancer 2 years ago

where do you find the MAF adapter i tried ebay and nothing????

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