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937 Posts
Discussion Starter · #1 ·
Dmeetro could you make this sticky plz :)

Please don't ask questions in this thread, only info to be added here

For new ones:

What is JF-T?

JF is the 2Liter V6 that was available in Japan in HC platform of 929/Luce. T denotes Turbocharged version of the motor. JF engined cars are rare even in japan so here we will only focus on the JF-T.

Standard 3Liter engine that was available across the world is JE (and its variants JE-XX)


JF-T uses BCP6E-11 NGK plugs, by the looks of things NGK no longer makes these so you will need to use BCPR6E-11 (no difference, just has a resistor in it). I wouldn't use any other over the counter plugs but NGK but if you favor another brand, shop attendant with a clue should be able to cross reference the plug to another brand... if they will give you a blank look... go else where :)

Distributor cap and rotor for JF-07 Distributor

To find out what distributor you have, look at the body of the Dizzy and there will be a sticker with the part number (all Distributers have JF-XX, even the JE motors)

Echlin part number for the cap is: EP132
Echlin part number for the rotor is: EP684

again just like plugs, if the shop does not stock Echlin, they should be able to cross reference to another brand.

in absolute dire situation you on JF-07 Dizzy you can use HC DOHC cap and SOHC rotor

Air Flow Meeter

If you have issues with AirFlow Meeter, you can get away using one from GD (1988-1991) mx6/626 turbo/tx5 turbo meeter. The GD airflow is a little larger in the opening though... have not noticed any problems on mine yet.


if you have Distributor with code JF-07 (Blue label) the only replacement you will find in Australia is from 1990 Sedan with SOHC JE(3.0). remember ONLY 1990 sedan.

Idle issues

if you have idle issues, check the little boot that connects the metal cooler pipe. these boots are IMPOSSIBLE to find. get a 3.5" silicone hose section, sweat for a while but stretch it on the throttle body (TB if was round would measure to about 3.75" so its not easy). take your cooler pipe to the good exhaust shop that would be able to weld on a oval extension to 3.5" to meet the silicone joiner.

in the worst case as a band aid solution you could get away using JE throttle body boot with 2" to 3" hose joiner (i had mine made at exhaust shop). There a few problems with this:
~the hose has much more flex in it then metal pipe, so there is noticeable response delay
~thanks to the turbo pressure you will be faced with 1" cracks every month or two.... turbo just shreds the standard JE Throttle Body Boot


Pads are the same as on standard JE equipped 929.

However, there are differences in brake hard ware... the booster is the same as HD (Largest in mazda range). the master is the same size as FC S4 from memory (very tiny difference between JE equipped 929)


Haven't dug too far into the engine yet, however the valve cover gasket is the same as on JE SOHC.
Timing belt and the tensioner is the same as a JE SOHC
Radiator is the same as JE as well EXCEPT ---->>>

Japanese radiator cap is different to Australian... it seals differently (about 2 millimeter difference) putting Australian cap on the Jap Radiator will increase the pressure in the top tank and will crack it sooner.

If you changed your radiator to Australian version, use Australian cap as Jap will not seal properly

Fuel Filter

There are two filters that are listed for 929... one has IN and OUT pipes on the same axis (cheaper) the other has IN and OUT on a small variation away from axis. ( you will know what i mean once you see them side by side). JF-T uses the cheaper one (thank god as the other one is almost $50). having said that, ive tried both and both of them work fine.

this is all i can think of, i'm sure that Nitros13 will add his chapter here ;)

931 Posts
Ok heres some info that i know.

Computer Differences
the series 1 (earlytype) jft computer has less connections than the SOHC 929 version, the series two jft looks like the SOHC 929 computer but inside it is much more sophisticated. heres some pics i took for your reference.

The top one is the Series 1 JFT Luce and the bottom one is the SOHC 929

The left one is the SOHC 929 computer and the right one is a Series 1 JFT Luce

LEFT: SOHC 929, CENTRE: Series 1 JFT, RIGHT: Series 2 JFT

Loom Differences
so this has been an absolute prick of a job. i have now found out there are at least 3 different types of loom in the Series 1 JFT.

The first is the early type, JF09 computer and Trans Computer. The computer as stated abouve has less pins than all other 929/luce computers. 4 Pin Dizzy and a Single big injector connector.

Next is the Mid Type, JF01 Computer and Trans computer. This computer has same amount of pins as a SOHC 929. It has a 6 pin dizzy and two injector connectors, one is a 3 pin the other is a 6 pin.

Last is the late type. Again, uses the JF01 computer and the dizzy has 6 pins as well but there is two 6 pin connectors for the injectors.

the ignitors are different between all 3 models early: JF118, mid: JF119, late: JF120

so, now i have my mid type loom, late type motor and early type car i was in a real fucked situation. So i have ordered the mid type injector loom and trans computer and i have worked out the loom will fit the 3 dash plugs with the exception fo one of them, i will have to cut and shut this plug.

931 Posts
Turbo Information
so i can confirm that the Turbo is actually a IHI the number looks to be a VJ109001

heres some progress pics.


no manifold, note knock sensor

mmm turbo

more turbo

pic of the turbine

another turbo shot.

serial number and model.


heres a good site for IHI turbos;pagina=RHB5

931 Posts
Computer and Dizzy Information
as some of you know i have run into some problems with putting the late model JFT in. the main is the wiring loom.

i have a late model manual wiring loom and a early model auto wiring loom.

i have to use the auto cause i cant find another manual box at this stage, i have to use the late model loom/computer because of the dizzy and the injectors, plus i want the CAS and the seqential injection that the later version offers.

Left: Early Type JFT. Right: Later Type JFT

This is the late model 6 pin dizzy that incorporates a CAS

This is the early model 4 pin dizzy


old stuffed engine (early type)
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