advance timing and starter motors?

[PrettyCoolWagon]

So anyone who's advanced their daily's factory timing will know the engine is harder to start, especially in winter.

Despite reading online, I can't seem to find any advice on how to directly counteract this hard-start issue..

My engine's the first gen 4afe.
I really like how much better it performs with advanced timing.
Bridging diagnostic terminal points E1 & TE1 and using a timing light, the standard timing is 10 degrees BTDC.
I used to run 16 degrees BTDC all day everyday, it was heaps of fun, ..but quite hot and loud, you could hear the exhaust pipe making metallic 'ping' sounds as it cooled down everytime I stpped driving and stepped out of the car =D

Now I'm running 13.5 BTDC, as a compromise. It doesn't perform as well, but it performs better than factory settings and it starts easier than 16 degrees BTDC. Still takes 2 goes though. (ignition on, then off, then on again) ..and she fires up no problem.

So I was reading, engines with higher compression can be harder to start, and this got me wondering if there are other stronger starter motors that might improve the hard-start issue. (smallport 16v / 20v etc.) ..but they're C-series gearboxes. I don't know if they'll fit.

My gearbox is E-series with an A-series engine block, like the supercharged MR2's and AE92's - but they have lower CR's, so maybe their starter motors aren't much different..

So does anyone know if there's a stronger starter motor that would fit?
(Flywheel is same type & diameter as AW11 supercharged - just has 6 bolt-holes to the crank instead of 8)

Would a camry starter motor be better?

Should I run different plugs?

Even if there is a starter motor that fits, Would a stronger starter motor even help?

What causes the hard-start?

[jondee86]

What causes the hard-start?

Combustion occurs before the piston reaches TDC. Pressure is exerted on the piston while it is still rising which generates a force that tries to drive the engine backwards, opposing the starter which is driving the engine forwards. If you have enough advance, when combustion occurs it can actually stop the engine turning for a moment.

Only a problem at cranking rpm. When the engine is running, by the time decent pressure is developed in the combustion chamber after the spark event, the engine has gone past TDC. But with a lot of advance you will experience "pinking" if you apply high load to the engine at low rpm. Basically the same cause, but the momentum of the rotating parts keeps the engine turning forward (instead of the starter).

Cheers... jondee86

[DX20VT]

Depends on what type of starter you have to begin with. It it conventional type, gear reduction or planetry gear reduction?

Another option is to make a circuit to stop spark until you build oil pressure,
that way the starter will already have the engine up to speed before any spark occours.

Will depend a bit on how fast your car builds oil pressure.

[Shakotan_Aaron]

.

But with a lot of advance you will experience "pinking" if you apply high load to the engine at low rpm. Cheers... jondee86

I think you mean pinging.


Try a larger cca battery?

[allencr]

I think you mean pinging.


Try a larger cca battery?

No, pinking.
http://lotus-europa.com/manuals/misc...erminology.htm
Also, won't a different/bigger battery just crank longer, not necessarily faster?
////
"Still takes 2 goes though. (ignition on, then off, then on again) ..and she fires up no problem."
This may be a technique issue rather then a starter problem.

[aus jd 2703]

generally the sign of incorrect timing on start/cranking is the motor kicking back.
if its slow to turn over then its the starter/wiring or battery.

one other point is most cars we are playing with that have 4a and 3s etc have old distributors and the reluctor sensors used in these for reference and sync are old and tend to generate less voltage at low engine speeds even more so on a hot engine. you can get around this with standalones but on a stock ecu you could try another dizzy but i im some what doubt full you will yield a noticeable result.

my 3s used to be extremely hard to start when hot at track days (haltech ecu) unti i changed some setting now it seems to start like a champ, not as good as new cars but it always starts first maybe odd second try. not bad for an old engine (22 years)

[PrettyCoolWagon]

Thanks for the reply guys.

Interesting comments about old distributors generating less voltage.
I suspect from previous years of playing with 4AFE's that either advancing or retarding too far can cook the sealed part of the dizzy (beneath the rotor)

Some observations.
(I ran 16 degrees advance timing all day every winter summer etc on 92 pump fuel no dramas - just the hard starts.

Definitely starts easier in warmer temps.

Larger battery does sweet FA
I've run a large battery for ages - makes no difference to starter motor.

However it makes me wonder if any mod's could be made in the following areas:

Increasing power to starter motor (larger wires etc.)

Increasing spark / voltage

Different plugs

cold start injector (?? ,,just guessing here)

[jondee86]

Heh... heh... heh... you young fellas today with your fancy synchomesh gearboxes and hydraulic brakes Just set your levers like is says in the manual and she will start first pop hot or cold.



Cheers... jondee86