SUPERCHARGER: Paxton/Nelson SN-2000 from Design Energy (Mariah) required approx. 20 hours for actual preparation and installation. Installation required re-routing engine wiring harness, careful shimming and alignment of serpentine pullies, upper radiator hose/neck replacement, removal of cold-start injector system and installation of remote boost dependent fuel pressure regulator. A conservative dyno pull yielded 212.2 RWHP which is more than a 60 hp increase. Design Energy is a small supplier that is a bit erratic with its support and advice . . . but they are the only source if this kit. I am currently pursuing a warranty claim with DE - stay tuned.
REAR TOE ELIMINATORS (Racing Beat): You're best off using a press to remove the old bushings. Ths is a larger job than one might expect and it takes several hours even if you have the right equipment. Makes the 7 much more predictable at the limit. Racing Beat is a solid and helpful supplier and they have now got a full online catalog (hurrah!). RB offers excellent advice.
ELECTRIC FAN: Flex-a-lite 150 from Summit Racing including thermostatic switch and mounting brackets. Brackets are massive but usable. The fan is adjustable for cut-in temperature. It can be mounted without removing the radiator but it's not recommended. Allow several hours. Keeps the 7 as cool as stock fan or cooler (in Ohio at least). Doesn't add power to the engine but DOES free up existing power to go to the wheels instead of the fan. Summit is mostly oriented toward American iron but their delivery is good and their pricing is okay.
OPTIMA BATTERY TO PASS. BIN: (Summit) Recommend at least 2 ga. cable (0 ga. is ideal). Routed cable between the carpet and tunnel on the passenger side to a bukhead terminal and into original harness in engine compartment. Used a 200 amp. audio fuse at the battery for short protection. Recommend only sealed batteries due to hydrogen gas potential from charging battery. Can be tricky, took me over four hours as I tried to be very careful about power cable and sharp sheet metal. This mod lightens the front end and reduces polar movement. Feels like it gives better turn-in response.
COLD AIR BOX: Built from a series of hand-fit cardboard templates which were joined and transferred to sheet aluminum - then bent, drilled and riveted. See pic/dims. Fitting the template is the time consumer - took me over four hours. I've seen over 40?fference between box and engine bay.
C's SHORT SHIFTER: (Mazdatrix) <See Mazdatrix site for installation notes> Buy replacement bushings and boots and do it all at once. 45 minute job. Nice short throw without excessive effort. I recommend filling the transmission with synthetic lubricant (Redline MT90) at this time - it makes a BIG difference in shifter smoothness. Mazdatrix has a broad RX-7 product line and a knowledgable staff (sometimes temperamental) - highly recommended.
BONEZ SUPERFLO: (Rotary Performance / Texas) [this exhaust setup is run during "emissions season" See "header" for normal setup] This is a good way to replace both of the front cats and the rear cat with a presilencer and a high-temp free-flowing cat all in one (monolithic) unit. I recommend, however, buying just a high flo main cat from Bonez (Rotary Performance) in case you want to go with a header in the future. Direct bolt-on job. Quality product with definate power gain. RP is knowledgable and they have a wide 7 product line . . .though they tend to over state product capabilities. Recommended.
RACING BEAT HEADER PRESILENCER: (RB) [usually installed - see above] This is an excellently constructed 2 into 1 header with heavy mild steel flanges fabricated for direct bolt-in fit - replacing the exhaust collector and all the cats. This exhaust front-end was ceramic coated at Performance Coatings of WA (fast service and good workmanship) and the resulting system is cooler underhood than the stock manifold. Installation is straight forward and takes an hour or so however it will cause you to have your O2 sensor and EGT (if you elect to put the probe in the "collected" pipe) 8 inches farther away from the exhaust ports than on the stock setup. Result is negligible to the O2 but I found EGTs to read 200 degrees cooler there.
RACING BEAT STREET/STRIP CLUTCH & PP: Excellent quality clutch for spirited street driving with probably 25% more clamping force than stock with little increase in pedal pressure. If you are going to go with a light flywheel (light steel from RB is nice) do it now. This is a good job to bite the bullet on and have it done at a shop with a lift.
[I have an ACT heavy duty clutch and pressure plate on the bench but haven't installed it yet. Stay tuned]
LIGHT STEEL FLYWHEEL (RB) Quicker throttle response and improved accelleration. Doesn't create MORE HP it just reduces the parasitic energy normally used to spin up a heavy flywheel. There is NO difficulty when starting from stop with a light steel flywheel . . . maybe with a super-light aluminum one there is, dunno. Pricy but worth it in my opinion. Quality flywheel/counterweight package.
BONEZ STAGE 1 PADS AND BONEZ SS BRAKE LINES: (RP) Good combination for firmer pedal and improved braking No noise, little dust and requires minimal warm-up to function. Bleed, bleed, bleed.
TII FUEL PUMP: Gives more FLOW for modified NAs and is a straight swap for NA OE pump except for trimming the rubber isolator a bit. First swap took over an hour, fourth time (that's a long story) took less than twenty minutes. YMMV.
[I have a Walbro 255 lpm pump on the bench but haven't installed it yet. Stay tuned]
PORTING: Templates for enlarging the 6-port 13B (M/trix) come as a sheet of aluminum with Dychem squares painted on it which are etched for port shapes. You need to cut out the port shapes in order to transfer the shapes to your (Dychem stained) irons. Actual port enlargements are conservative but this is just what I wanted with a boosted, high compression engine. Mazdatrix is NOT eager to support porting projects and are unlikely to answer porting questions.
INJECTORS: I am using 460 cc. primaries and 550 cc. (SR Motorsports) secondaries to support high end boosted-flow requirements. For cleaning and flow-testing Marren Motorsports is okay (but slow). Clean injectors minimze flood tendencies and assure even/expected flow. Marren advertises 2 day turnaround . . . my experience puts their turnaround between 2 to 3 weeks. Not really recommended - but the options are limited. . . you might try RC Engineering for quicker turnaround.
OIL SYSTEM MODS: I replaced the stock rear oil regulator with an 80 psi. one (RB), replaced eccentric oil injection springs and balls with Weber 2mm. jets (RB) and replaced the stock oil pump with a TII one. . . I also replaced the eccentric bypass oil plug with a non-bypass plug (M'trix) which puts oil through the engine ALL the time (I'd rather have a slow warm-up WITH oil than find I have a quick warm up and NO oil circulating). I removed oil injection system all together, plugging injector holes with bolts/washers and the injector pump opening with a cover plate. Overall engine oil flow should be increased significantly, oil temps. should be reduced and the amount of heat carried out of the engine should be improved. With premix being used in lieu of dirty engine oil in the intake charge - engine should remain cleaner. All difficult to prove but looks good on paper. The 80 lb. regulator makes the stock oil pressure gauge read about 95 lbs - but there are no observed ill effects.
EIBACH PRO SPRINGS: "Pro" means progressive . . . these springs are soft when gently cruising but as they compress they become much firmer. NOT for racing where linear feel is preferred but these are GREAT for the street. (M'trix) Lowers the car 3/4" and does not make daily driving any harsher (perhaps a little softer) but firm up immediately under use. Again, I recommend using a shop and lift. Lowers CG and reduces roll.
TOKICO HP STRUTS blue: (M'trix) Good replacement for stock shocks. Slightly firmer, non-adjustable, economical. For racing the tokico 5-way adjustables are possibly better.
GAUGES: A/F gauge is Intellitronix (Summit) and utilizes a series of LEDs. It functions well enough - tapping into the stock O2 sensor - but is cheap. I had to re-solder after the faceplate popped off of its own accord. Not recommended. Boost gauge is from VDO (Pegasus Racing) and is the only one I could find with a 0-15 lb. scale w/no vacuum. With the supercharger the needle uses up to 2/3 of the scale where most others with 30 lb. scales I would only register 25% - too small a sweep to be significant. I took a "T" in the boost line to the BDFPR. The EGT is Westach (Pegasus) and reads 700?o 1700?llowing for hot RX-7 exhaust (<1400?t 3500 rpm lean cruise) NOT to max the scale. I used the 3/16 probe and SS hose clamp installation kit instead of tapping the exhaust collector. Life expectancy results will follow. Pegasus Racing is just that - a racing supplier. Good products, good info but not very rotary-wise.
PLUG WIRES Magnecor 10mm. (RP) wires are probably overkill but I was concerned with underhood temperatures with the supercharger. After 2 years they are still delivering spark, are still pliable and still fat.
VACUUM LINES All vacuum lines have been replaced with silicone (Baker Precision & Summit Racing). About 10' of 3mm. about 4' of the 6mm. about 4' of the 8mm and a few feet of 10mm. CAUTION: Some suppliers are starting to ship silicone hose that is thin wall . . . I recommend using only 3mm. id. hose that has a wall thickness of 3mm. also (9mm. diameter vac hose for 3mm id.) Thin wall, small diameter, hose WILL kink.
A'PEXi SUPER AFC: (SR Motorsports) Ray Lochead of SR offers outstanding customer support. He's a top racer (9.89 in stock body 3rd gen) and still is willing to support his sales personally. The S-AFC (Super Air Flow Converter) allows tuning the flow of the 550s when the ECU thinks that they are 460s . . . then again, the ECU doesn't know that it is being blown either.
MSD 6A Ignition - This capacitive discharge / multiple spark ignition system was installed in about an hour and was chosen to provide a hotter spark to the dense (supercharged) gas/air mix at boost. Frankly, I have seen virtually NO difference between the MSD and stock ignition performance and I sometimes leave the 6A off the car for weeks at a time without realizing that I have forgotten to re-install. YMMV.
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