Page 'O DIY Intakes
By Randy Stocker
Custom intake plumbing and air filters are easy and cheap to construct yourself for the average do-it-yourself'er. There is no reason to spend $150-400 for a prefabricated unit. The design possibilities are endless, here is my chronology of the intake systems that I have made over the years as well as others that have submitted their concepts. Note, I always retained the factory resonance chamber in each design (see my Flowmeter Q&A page if you need to ask why)
The most common and inexpensive airbox mod. 'Swiss cheese' the bottom and front of the lower airbox. Circa 1993
Cutting a hole and adding a tube to the front of the airbox (I think the tube was from a 87 Cavalier). Circa 1994
Relocate the airbox closer to the TB for better throttle response. Move tube back to rear of box so the inlet is near the headlight. Circa early 1995
Turn box upside down and cut off bottom half exposing the K&N drop-in airfilter element. Circa late 1995
Later added K&N foam filter to the top of the regular filter (via velcro) to keep any large debris and water off the filter
Added RX-7 flowmeter so took opportunity to add K&N cone filter. K&N sells hundreds of filters in all sorts of shapes and sizes, I choose the model RB-0910 (3" opening by 4.5" H and 5" W, w/5 degree flange angle). The prices vary but this one was $35. Circa 1996
Two views of the RX-7 flowmeter implemented on wifes 1992.
Owners of 94+ Miata's have an easier time making DIY intakes since the flowmeter is already a round shape and readily accepts aftermarket filters without adapters. Here is Kit Wetzler's DIY intake for a 94+
Bill Rockoff's innovative use of zip ties.
Eric Moon's variation of the 'swiss cheese' theme. He sectioned out the lower front of his 1.6 airbox
John Suchak's dual snorkel intake.