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Obtain an Electronic Ignition distributor from an E15 engine such as from an N12 Nissan Pulsar. Fit a drive gear from an A series distributor. Fabricate a hold-down bracket. Plug it in. Cost is about $65 AUD for a used distributor from the wreckers.
Contents |
Sourcing
Obtain an E-series distributor from one of the following engine:
- E15S (single carburetor)
- E15I (Injected, central throttle body injection)
- E16S
- E16I
This is the same type of Hitachi distibutor used on A12 Sunny Trucks with factory EI, and also used in certain Ford, Mazda and Mitsubishi vehicles. So cap & rotor parts can be purchased in just about any country.
You want to get this type, Hitachi D4R and D4A types. Some Mitsubishi T4T types are also fitted with these guts:
Or this type, Mitsubishi with top-mounted centrifugal advance:
You can also use this E15 "Matchbox" type (same as the B310 Electronic Distributor Swap), which was used on a couple of Japan-market E-series models. It is wired the same externally.
- B11 JDM 8110-[8608] E15S.(GL,LT).F5
- N12 JDM 8205-[8610] E15S.5F.(TS,D,FC)
CAUTION: The E15ET turbo and some E16I engines use a different type of distributor than we will consider here. It looks like this, and has none of the familiar guts inside:
D4P distributor -- Easily identified as having no vacuum advance unit. Don't get this type as it requires a spark controller (computer) like the E15I engine ECU.
For more details, see E-Series Distributor.
Instructions
- remove gear from A-series distributor and fit to the E-series distributor
- Create new (or modify existing) housing clamp-down
- Insert distributor with correct timing. See Distributor Installation
- Connect the two wires and enjoy maintainence free driving (no more yearly points changing)
Gear Changeover
E15 doesn't use a gear, but is otherwise nearly identical to A15 distributor:
Top one is from converted E15, while lower is from A10/A12.
The E15 has been converted for A series. Note that it is fractionally longer that the A series when comparing shafts.
Using a 3mm pin punch, remove the roll pin from an A-series distributor. Remove the gear from the shaft. Do the same for the retaining ring on the E-series distributor. Fit the A-series gear onto the E-series distributor shaft. Before drilling a new hole for the roll pin, ensure there is sufficient end float at the top of the gear. (Use a shim or similar when drilling). The clearance required is minimal but is needed to ensure the distributor spins freely. What is the spec for this clearance on the original distributor?
For the adjuster bracket unscrew and remove the plate from the A-series distributor. Install onto the E-series and mark it with a scribe on the original alloy (part of the housing) adjuster bracket.
One method for fixing the adjuster plate is to drill and pin it to the housing. (Use the leftover roll pin) and ensure it sits above the bottom surface of the plate. Alternativly, use a small (3mm) bolt and lock nut to keep the adjuster plate in place, at high revs the roll pin could loosen.
Mounting Flange
You don't need to modify the dizzy casting to install in an A-series -- it fits in just fine. However, the E-series distributor's hold-down bracket doesn't line up with the block's bolt hole. Also, If you try to line up the hold-down bracket, the vacuum advance hits the block:
Easy solution: don't try to line up the bracket. There is plenty of room in a 1200 for any position in-between these two.
Limit of ANTI-clockwise rotation (on late-model engine):
Limit of clockwise rotation:
But how to secure the dizzy to the block? You could create a Chevy-style "fork" hold-down bracket to secure it. Then leave the dizzy's own bracket hanging off the distributor unused. It is cast in with the housing so doesn't come off.
Or, for a more OEM look, you can drill, grind, cut and otherwise modify the E15 dizzy casting.
It also depends on whether you have an early or late A12.
Hold Down Clamp
To secure the dizzy to the block, fabricate or modify a Chevy-style "fork" hold-down bracket to secure it.
One with a long slot as in this photo might fit. The E15 dizzy has the right surface for the clamps finger's to grab.
When using a clamp you will leave the dizzy's own locating flange hanging off the distributor unused (it is cast in with the housing so doesn't come off).
Or you could use an Austin clamp (see below).
Custom Bracket
You can fabricate a special bracket to mount it.
Austin Clamp
Beattie used an Austin Mini dizzy clamp on a E15S Mitsubishi type. The Austin clamp is similar to the Chevy clamp but fits right to a Late block (1973-up) -- once the original casting or the E15 dizzy was ground off.
beattie: I ground all of the alloy adjuster part off and used the dizzy clamp off a Mini. Fits perfectly around the dizzy shank and lines up perfectly with the hole! Dont ya just love that?
This is a newer type that may or may not work if you cut one end:
Austin CLAMP HOLDDOWN
$21.95 at minimania.com
Custom Bracket
You can weld a tab onto the stock Datsun 1200 dizzy bracket, the secure the dizzy from below to the tab. This is not a clamp, but is secured by a bolt. Then the whole unit will bolt to the block very nicely.
For Early blocks (1967-1973) A10 and A12. Newer blocks could be treated similarly.
Early vs Late A-series
Do you want to fit the distributor into an early A10 or A12 engine? Or a later A12/A14/A15?
Late (post-1973) A-series engines the distributor securing bolt to the rear of the dizzy bore hole. If the E-series distributor was bolted straight in, the canister would hit the block, but the pre-1974 block has this bolt in about the 4 o'clock position. This would place the canister facing near to the opposite position, away from the block.
Early A-series (up to 1973) engines have the distributor-securing bolt hole almost straight forward of the dizzy bore hole.
Left: Early A-series plate (slots on opposite sides)
Right: Late A-series plate
Late vs Early A-series distributors
Put the stocker A-series flat plate on the E-series distributor:
Hacksaw Method
One way is grind the original bracket part off so it won't foul on the block. Fit a Datsun A-series bracket onto the distributor.
shoom: what I found was that the A15 adjuster plate fitted over the bottom of the [Hitachi] E15 dizzy. funnily enough there is a painted dot on the bottom of the dizzy that exactly matches the location of the original A-series securing bolt. so I just drilled and tapped a hole out and walah, plate fits. I then ground off the original adjustment slot on the body and with a little bit of buffing you cant even tell it was there before.
1. Cut the A15 flat bracket and bolt it like so to the E15 dizzy
2. Then grind away unneeded parts of the E15 cast bracket
Finished product:
Another way to do it:
Installation
Install the new distributor (see Distributor Installation. Use the old adjuster plate as a spacer. This is necessary as the hole on the gear sits higher than the hole on the shaft. Thus drilling a new hole on the shaft means the gear is further down the shaft (The distance between the two holes can be measured to be approximately the same as the thickness of the spacer plate.
The rotation of the body relative to the block will be different from a stock distributor. for example (depending on your mount mod method):
Wiring
E15 dizzy has two wires. The E15 dizzy wires are long enough to reach the coil, so no extra wires are needed. Connect them as follows:
- Black/White wire to 12V ignition circuit -- the POSITIVE coil connector for EI coils.
- Blue wire to NEGATIVE coil connector
CAUTION: If you are still running the stock 1200 coil, connect to the POSITIVE side of the resistor, not to the COIL POS, which won't see 12V during normal operation. If you engine will start, catch for a moment but die when you release the starter, this is likely your problem.
The A-series wiring colours mentioned are from a 1980 Sunny:
- The original white wire which connects from the negative side of the coil to the points is not used and can be removed
- The black wire from the tab on the vacuum diaphragm can also be left off. An optional condensor connects here to reduce radio interference.
- The same applies to the black wire from the positive side of the coil to the body via a capacitor (condensor).
Coil
You can use the stock 1200 coil as long as you leave the ballast resistor in place.
For best performance, use the Pulsar coil or a performance coil. Any 1980s Datsun-Nissan EI coil should work just fine and are as 'hot' as a Bosch GT40 coil. With this type of coil, bypass the stock resistor. Remove it or simply jump a wire (short) across both terminals.
Performance
When using the EI coil, regap the spark plugs to 0.44 inches for maximum spark performance.
Has anyone dynoed the different configurations?
Question: Is it reasonable to expect a (slight) increase in power?
Answer: No. Electronic Ignition will make your engine run at peak spark month after month with none of the losses that points have as they wear. Thus you should get performance equivalent to a newly installed and correctly adjusted set of points. Add to that differing vacuum and mechanical advance curves and the difference is probably a wash. However if your tune was marginal before it may pick up a few HP -- but so would new points and properly adjusted fuel mixture w/o Electronic Ignition.
For best performance, get your dizzy recurved. This applies to stock dizzies or EI dizzies. You can do this yourself if you are patient and methodical. Start with Timing.
beattie
beattie's E15E distributor
- with Top-weights (visible centrifugal advance)
- similar to circa 1983 Mazda 626 GC (AU)
- Cap is taller than the usual E15
Cap and rotor: The "standard" E15 rotor is the conventional style, same style as the A-series that is. This E15E Distributor has a round item that is fastened to the top plate where the centrifugal weights are and covers them completely. So the cap needs to be taller then the "standard" E15 item!
I don't understand this bit but I'm leaving it in until I clarify it.
Part numbers are
- CAP-BOSCH GM554
- ROTOR-BOSCH GM555
Need to confirm alternate sources for distributor. Mitsubishi 4G15?
Models
D4R83
See D4R for Hitachi D4R series
D4A
Hitachi D4A series
Mitsubishi T4T
For more details see T4T
Cap & Rotor
Which cap & rotor you need varies by the distributor type, which is stamped on the distributor housing. See the links above for the various types.