coil questions

[ninjamuder]

hey guys... newbie to the fj here......

got a quickie for you.... what is the primary, and secondary resistance on the stock coil??...need info , as im researching "alternatives".......

[craigo]

Hello and welcome!!!!

This might just be what you are looking for:


Good Luck,

CraigO

[Pat Conlon]

Very cool Craig, thank you!  Do you have one of these timing tables for the digital IC (non vacuum) used on the later FJ's 

Hell, how about both 2nd and 3rd gen FJ's?  I wonder if there is any difference in the timing curves between the generations?   

[mz_rider]

Very cool Craig, thank you!  Do you have one of these timing tables for the digital IC (non vacuum) used on the later FJ's 

Hell, how about both 2nd and 3rd gen FJ's?  I wonder if there is any difference in the timing curves between the generations?   

Pat,

Here are the ignition advance curves from my factory manual for Euro markets. The top is for the early FJ1200. The lower is '91+ models. The solid line is the full power model we got in the UK. The middle line is slightly retarded possibly to meet 100bhp limit in some countries. The lower line is for Switzerland who had severe power restrictions.



Stuart

[craigo]

Sorry Pat,

That is all I have.  I bought this manual on Fleabay for about $10, if memory serves.  I wish it had more info on the 1990 bike I own as it's all about the 84 FJ1100.  So I really have no idea if the info I am looking at is applicable to my 3CV.  

But that's just ebay, hit and miss,

Look in your email for a nice present (maybe)

Cheers,

CraigO

[Pat Conlon]

Thanks Stuart and no worries Craig.

This is interesting, the difference in the kookaloo zone timing between the 1st, 2nd and 3rd gen. FJ's

Kookaloo zone being defined as from 5k rpm to 9k rpm...and for comparison purposes not considering the detuned Swiss, JDM FJ's

1st Gen: '84/'85 cruising (low vacuum) 35*@5k to 37*@ 9k rpm ...yet.. WFO with the butterflies open (high vacuum) 45*@ 5k rpm to 50*@9k rpm.

2nd Gen: The '86-'90 FJ's are not so aggressive 38*@5k rpm (peak at 40*@5200) tapering down to a measly 37*@9k rpm  
That's a full 10 to 15* less advance than the '84/85's....I did not know that

3rd Gen: is even more sedate, a flat 35* from 5k to 9k rpm... ho hum.... That's the timing zone on the 1st gen at low vacuum cruise.

I realize that a PC programable Dyna 2000 ignition with custom advanced curves is the best....but for now I'm sticking with my '84's oem vacuum box.

I did not realize the timing difference was so great. Thanks for the lesson guys.

Reinforces the value of a 3*or 5* timing advance plate on the later FJ's huh?

Cheers!

[SlowOldGuy]

1stt Gen: '84/'85 cruising (low vacuum) 35*@5k to 37*@ 9k rpm ...yet.. WFO with the butterflies open (high vacuum) 45*@ 5k rpm to 50*@9k rpm

Pat,
I think you got that backwards.  At cruising, there is high manifold vacuum while at WOT the vacuum is low
You can crank in the advance when cruising, but it needs to be retarded during acceleration (low vacuum) to prevent pinging and detonation.
(I think)

DavidR.

[Pat Conlon]

I thought about that David.  I guess it depends on which side of the throttle plates the vacuum signal is taken from....

Throttleplates closed = High vacuum with vacuum port on the engine side of the plates, and the opposite, a low vacuum signal with the vacuum port on the air cleaner side of the plates.
Throttle plates open = a high vacuum signal on both sides
A high vacuum signal would be the 150mmHg timing line correct?  i.e A higher column of mercury for a higher vacuum signal?
A low vacuum signal would be the 50mmHg line?

I keep thinking of the vacuum advance on my '55 T bird's 292 distributor. For acceleration, when you open the throttle plates on the 650 Holley the High vacuum= advanced timing on distributor and  at cruise with the only throttle plates partially open results in lower vacuum= lower timing on the distributor.
It's been so long since I've used a timing light.....

I did try and rationalize the logic in my mind.....but then again it's not the first time I've been backasswards and it won't be the last.   

1stt Gen: '84/'85 cruising (low vacuum) 35*@5k to 37*@ 9k rpm ...yet.. WFO with the butterflies open (high vacuum) 45*@ 5k rpm to 50*@9k rpm

Pat,
I think you got that backwards.  At cruising, there is high manifold vacuum while at WOT the vacuum is low
You can crank in the advance when cruising, but it needs to be retarded during acceleration (low vacuum) to prevent pinging and detonation.
(I think)

DavidR.

[FJTillDeath]

In this debate I am routing for PAT!

Go FJ 1100s

The guys on the 1200s are always gonne be sore about the smaller engine cc 1100(with a bigger fuel tank) is sportier than them

Oh and thanks Craig and Stuart for the diagrams. Took me a while to figure out how to read em(still not 100 percent certain) but great for knowledge

[Pat Conlon]

In this debate I am routing for PAT!

I dunno Jesse, don't bet the farm on me. What David said makes sense.(which is usually the case)
Now that I think about it, isn't the vacuum port feeding the signal to the '84/85 IC  located behind the throttle plates? (between the throttle plate and engine)
So that would mean with the throttle plate only partially open during cruise you would have a higher vacuum signal...... which would mean more advanced timing?

Unless I've been stuck all my life in some alternative parallel universe, to promote or enhance acceleration you want the vacuum signal to advance the timing.

[SlowOldGuy]

Unless I've been stuck all my life in some alternative parallel universe, to promote or enhance acceleration you want the vacuum signal to advance the timing.

Pat,
I've seen this both ways over the years in autos.  It's venturi (carb throat) versus manifold vacuum (engine side of throttle plate).  They react opposite to the throttle.  If the distributor is hooked up to venturi vacuum in the carb throat, then the vacuum signal will increase as you open the throttle, as the air speeds up in throught he carb throat, providing additional advance during acceleration.  This appears to be old school as it was the way it was done on my old '68 Chevy Truck (with a big block 396!).

The more modern Chevies ported the distributor advance to manifold vacuum (think FJ between throttle plate and engine).  When you open the throttle, manifold vacuum plunges and doesn't recover for quite some time as the vehicle speed "catches up" with that particular throttle position.   Timing ported to manifold vacuum receives a strong signal at idle and at steady state (cruising) throttle positions giving more ignition advance.  Opening the throttle to accelerate causes the vacuum advance to retard the ignition to reduce pnging or detonation (I'm guessing here).  That appears to be how the FJ ignition uses the "boost signal" according to the diagram.  It's still getting spark advance, but under high throttle conditions (low vacuum = -50mm Hg) the advance curve is not as aggressive.

This brings up the question of what happens when the boost signal is absent?  Seems like you'd always get the "low vacuum" condition and lower advance.  Keep debating, I'm not convinced I'm right, just throwing my logic out there for consideration.

DavidR.

[SlowOldGuy]

In this debate I am routing for PAT!
Go FJ 1100s
The guys on the 1200s are always gonne be sore about the smaller engine cc 1100(with a bigger fuel tank) is sportier than them
Oh and thanks Craig and Stuart for the diagrams. Took me a while to figure out how to read em(still not 100 percent certain) but great for knowledge

Uh, I happen to have an '85 1100 as well as a '93 1200.  Whereas Pat is the proud owner of an '84 1100 and '92 1200.  He just bought each one a year too soon.  I waited until all the bugs were worked out.  :-)

If you want to learn, then read carefully.

DavidR.

[Dan Filetti]

In this debate I am routing for PAT!

Pat is a smart guy and all, but betting against David on a carb issue, any carb issue, is just plain foolish.  He has forgotten more about carbs, than most of us will ever know.

Dan

[FJTillDeath]

True, what David says makes a lot of sense even when I put my reasoning by it. I didn't actually know you owned an 1100 as well, although i wasn't trying to come across as offensive. I was more looking at a reason to prove the 1100 was better in someway. I suppose it still has its ups, but its true when the say the 1100 was only the predesessor and building block for the 1200..

Oh and thanks for explaining things so clearly so that guys like me can understand

Although it does help to have a science background

[andyb]

Just because it says 1100 or 1200 on the outside, don't mean that's what it's got on the inside.... Pat's got onna them bigass fancyshit motors in his ride....