FAQ/Bolt Thread and Pitch List

[djmtsu]

My car seems to use a lot of oil. How often do I need to check it?
Everytime you get gas, you should check your oil level. The Rotary motor by design is supposed to inject oil into the engine based on throttle position. If you keep your foot on the gas a lot, you will use more oil. It is normal to use about 1 quart of oil every 1000 to 3000 miles.


Can I use synthetic oils in my Rotary engined car?
Yes and no. Mazda officially does not recommend the use of synthetic oils in rotary engines, however, long term and racing use has shown that the better synthetics (Redline, Amsoil, Neo, Royal Purple, Mobil1) are perfectly fine to use in a rotary engine, and will generally result in a 1 to 2% horsepower gain. However use of poor quality synthetics (like Valvoline, Castrol Syntec, Havoline, Etc) will result in build up due to high ash content left from these oils when they are burned. It is believed that is why Mazda did not recommend synthetics, because the couldn't pick favorites.

Other notes:
The Mazda Factory racing departments recommend and use ‘synthetic’ oils including the winning 1991 Leman’s 20-G 4 rotor Mazda 787B.

MazdaComp USA printed manual (now Mazdaspeed) recommends the use of synthetic oils for racing conditions.

Redline, Amsoil and Royal Purple Synthetic Motor Oils have been used in rotary engines (both race and street) for ten plus years with excellent results.

Most Synthetic Motor Oil is compatible with the bearing material, sealing elastomer's, and combustion seals used in a rotary engine.


What oil should I use in the FC?
According to Mazda:
In starting and operating temperatures below 20F, use 5W30
In starting and operating temperatures between 0F and 80F, use 10W30.
In starting and operating temperatures above 30F, use 20W50

As far as brand any good quality oil that meets the API SL or SM standards should be fine.


How do I kill that buzzer in the dash that goes off when the cooling system or oil is low?
You need to bleed the coolant or fill the oil. The buzzer is there to help you from blowing up your motor.

I am having trouble keeping the car cool
Do you have:

OEM thermostat? (of KNOWN condition) do not use aftermarket thermostats like Stant in 86-88 engines
The plastic Undertray under the radiator and front of the engine?
A radiator with a clear core and not too many bent fins?
Two belts running your water pump?
OEM rad cap? (of KNOWN condition) (note: the stock pressure ( .9 bar) radiator cap suggested for proper cooling and system health).
A coolant mixture of at least 40% coolant, to 60% distilled water (do not use tap water) or 50/50 mixture (recommended in climates that drop under 0F).

I want to install an electric fan. How well will it cool? How much power does it give me? Which fan, and how do I install it?
In short, you gain a small amount of throttle response when free-revving in neutral, and any power gained (less then 1HP) is almost immeasurable. Cooling will be no better then using the stock clutch fan since the fan is only used at idle or very low speed driving, and it is the thermostat that regulates the temperature of the engine and not the fan. There's really no compelling reason to install an electric fan unless you need the space (FMIC, 20B install, etc.) or your stock clutch fan died. Remember that the stock clutch fan freewheels when it is not needed, so it doesn't suck any power from the engine.

[djmtsu]

How much Horsepower did my car come with from the factory?
86-88 NA = 146 HP @ 6500 RPM w/ 138 Ft/lb @ 3500 RPM
86-88 Turbo = 182 @ 6500 RPM w/ 183 Ft/lb @ 3500 RPM
89-91 NA = 160 HP @ 7000 RPM w/ 140 Ft/lb @ 4000 RPM
89-91 Turbo = 200-202 @ 6500 RPM w/ 196 Ft/lb @ 3500 RPM
Infini IV = 215 @ 6500 RPM w/ 206 Ft/lb @ 3500 RPM

What type of bulb is used in my USA spec MAZDA RX-7 in the..

High & low beam headlamp
H6054
H6054ST Silverstar High Performance Lighting: the whitest and brightest Halogen

Parking light
1157

Front turn signal
1157

Rear turn signal
1156

Tail light
1157

Stop light
1157

High mount stop light/Third Brake light
1156

Fog/Driving light
H3C-55W

License plate
168
89

Back up light
1156

Front sidemarker
194

Rear sidemarker
194

Ash tray
158

Map light
168

Dome light
DE3175
168 (spot lights on models equipped with factory sunroof)

Trunk/Cargo area
DE3022

Instrument-general
158
74

Hi-beam indicator
158

Automatic transmission indicator
158

Directional signal indicator in dash
158

[djmtsu]

Can I install the Turbo II transmission into an NA?

Certainly. But you need to also install:
-TII flywheel, clutch, pressure plate
-TII slave cylinder
-TII starter
-TII driveshaft, differential, axels
-Adapt the wiring.

MazdaTrix (www.mazdatrix.com) makes a TII transmission to NA rear end driveshaft, so if you don't want to swap your rear end, you can use that shaft instead.

Can I install the RX-8 6 speed transmission into my 2nd Gen RX-7?
5th gear on the FE tranny is the same as the 4th on FC trannys anyway, so there is no real advantage of using the RX-8 tranny, and 6th on the FE tranny is actually taller (.83 vs .71) than the FC, resulting in lower gas mileage at highway speeds.
Using a RX-8 tranny would be like adding a extra gear between 2nd and 3rd to a standard 2nd gen RX-7 M or R type transmission.

Add in, that the RX-8 6 speed transmission is also about 4 inches too short, forcing you either to relocate the shifter 4 inches forward in the car, or move the engine 4 inches backward (towards the firewall) to make it fit in the stock shifter location.


Did my 2nd Gen RX-7 come with a Limited Slip Differential?
Only the following USA model 2nd gen RX-7s had a LSD from the factory:
86-88 GXL
87-91 T2
88 GTU
89-90 GTUs (however not the 89-90 GTU)
It is also rumored that a few rare 91 coupes with both the A (upgraded the interior trim, added a power sunroof, tilt steering wheel, cruise control, and 4 piston front disc brakes and vented single piston rear brakes) and the B package (leather seating, a CD player, and rear cargo cover) came with a LSD, but you should note that Mazda denies that any FC other than the T2 came with a LSD in 91). You can also tell by looking at the differential as there will be a LSD tag on S4 cars with a LSD.

Non US models with LSD info to come