Edlit615

Im finishing up my rebuild on a 13B-REW and ive got some small things left to get (front running gear stuff mainly) and have been trying to find any information on wether or not theres any difference in parts on the blocks (ie sensors, front running gear, electrical plugs, etc.) that i should know about. I work at a mazda dealership here in AZ and our database doesnt really give much info on technical things like that. The block i have does not have original housings so there is no engine code next to mazda 13b logo. Also looking to see if there are any other identification marks on the rest of the motor that would be useful.

Any info would amazing!

j9fd3s

iTrader: (3)

i'm not sure i understand the question, but this is the internet...

from 1992-2002 the actual engine block does not change very much. the front iron changes from the N3A1 casting to the N3F1 casting (i think 96-97? too lazy to look), in conjunction with that the front cover gasket turns metal, and the front cover O ring goes away.

change # 2 is the rotor housing oil nozzles, the 99+ cars have an improved oil metering system, the 93-98 housings had a slotted nozzle like a flat head screw, and the new ones have no slot.

and that is it for the internals.

externally, the sensors and injectors and coils stay the same, but the vacuum rack, and some of the turbo plumbing change a little or a lot depending on what it is.

DaleClark

iTrader: (55)

Yep. The short block itself is pretty much the same 92-02. VERY minor differences.

The only differences have been external - the 280hp twins, the revised Y-pipe, going from the rat's nest to the black box, etc. That's all 96 or 99 in Japan. In the US 93-95 it's all pretty much the same externally save for very minor things - EGR, PCV valve removed in 95, etc.

Dale

billyboy

Late block, oil pressure port has a plug....and no pressure sensor.

Sgtblue

iTrader: (16)

When did they do away with that thin plastic upper intake to lower intake gasket?
Also if “running gear” includes transmission, there were changes in 5th gear synchro and clutch fork from 93 to subsequent years.

j9fd3s

iTrader: (3)

the gasket turned metal in 1996 or so. the transmissions are kind of their own thing, the fundamentals stay the same, but there are lots of little changes, the 5th gear stuff happened really early, like 1994. the design of the transmission makes life hard for 5th gear...

IRPerformance

iTrader: (41)

Casting on front cover changed including the style of the timing mark, updated oil nozzles in the rotor housings, switch to 2 piece apex seals (i forget what year, somewhere around 2000), screw in plug in the rear iron for oil pressure sensor elimination (removable)

REnaissance_Sle7in

iTrader: (8)

I'm guessing the only reason this was done was due to the change in the gauge cluster from oil pressure to boost pressure?

DaleClark

iTrader: (55)

I would imagine so, no use installing an oil pressure sender if there's no gauge to display it.

Dale

IRPerformance

iTrader: (41)

Exactly. We remove the plug and reinstall the factory oil pressure sender into the new motors.

Mazderati

iTrader: (3)

Summary of running changes on the Mazda assembly line:
(Assembly month/year printed inside driver's door)

<1993 Models>
Dec. 1, 1991: First 1993 RX-7 rolls off the assembly line

Feb.10, 1992: Redesigned wheel center caps

Apr. 30, 1992: Redesigned front glass guide (power windows)

May 11, 1992: Redesigned circuit logic of torque reduction
control (Don't ask, I have no idea!!)

May 20, 1992: Tie down holes underneath cars added for ease of
transportation. Dealer must install hole plugs to
prevent rust.

May 31, 1992: Redesigned upper A-arm bushings, modified front
windshield molding, redesigned engine mount,
redesigned steering rack boots

June 7, 1992: Redesigned alarm to function if door opened before
engine stopped

June 10, 1992: Flange added to rubber mount washer for intercooler
hose. The old washers break apart.

July 2, 1992: Redesigned ECU for 5-speed RX-7, redesigned hood to
prevent squeaking

July 10, 1992: Redesigned intercooler hose with stronger material

Aug. 4, 1992: Redesigned black interior trim pieces to prevent
peeling (Although some cars produced after this date
have experienced the peeling trim problem)

Sep. 30, 1992: Redesigned ECU for Automatic Transmission RX-7

Nov. 30, 1992: Redesigned rear hatch hinges

Dec. 2, 1992: Redesigned shift select spindle to increase
accuracy of shift pattern and prevent damage to
5th gear synchros due to missed shifts

<1994 Models>
Feb. 10, 1993: Redesigned turbo relief vacuum hose (3000 rpm
hesitation),redesigned door checker, redesigned
steering rack boots (larger diameter) redesigned
glove box lamp cover (light stayed on with door
closed)

Aug. 1, 1993: Redesigned turbo charger housing (Mazda says this
was to make the part easier to manufacture.)

Oct. 8, 1993: Redesigned clutch facing material for longer life

Jan. 21, 1994: Redesigned following cooling system parts:

old -> new old -> new
PART NAME MATERIAL DESIGN TEMP(C)
------------------------------------------------------------
Water pump mech. seal NBR -> EPDM 125 -> 150
Water level sensor Polyacetal -> PPS 125 -> 200
Radiator upper hose Polyester -> Nylon 130 -> 150
Filler cap NBR -> EPDM 130 -> 150
Filler cap body Nylon -> Aluminum 130 -> 235
Thermostat gasket NBR -> EPDM 125 -> 150
Water hose(throttle body)Polyester -> Nylon 130 -> 175
Water hose(sep tank) Polyester -> Nylon 130 -> 150

ALL CARS BUILT BEFORE THIS DATE ARE SUBJECT TO A
FACTORY RECALL TO PREVENT ENGINE COMPARTMENT FIRES.

Mar. 23, 1994 Redesigned radiator cap. Pressure lowered from:
1.3 +/- 0.15 kg/cm/cm to 0.9 +0.25 kg/cm/cm
-0.05

Sept, 1994 Redesigned fuel hoses to withstand higher temperatures
and added fan relay to allow cooling fan to run for 10 minutes
after engine was shut off.

ALL CARS BUILT BEFORE THIS DATE ARE SUBJECT TO A SECOND
FACTORY RECALL TO PREVENT ENGINE COMPARTMENT FIRES.


https://www.rx7.org/public/3RD.html

Edlit615

Thank you guys for all of the help!! Mainly trying to find out what front gear i need if any is specific (timing stuff, pullies, basically trying to find what is specific to this motor from the front iron forward). Here is another picture, one of the housing stamps.

Edlit615

So n3A1 stamps on all irons Would point to it being a motor out of an S6 car, correct?

j9fd3s

iTrader: (3)

yes, front iron changes for the Version 4 FD, 1996

j9fd3s

iTrader: (3)

every FD is the same...