How To Adjust Timing in the FJ80

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Iceaxe

Iceaxe

I am my rig's nemesis.
10 Year
Joined
Sep 16, 2011
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578
Location
Reno
Guys, I've searched around and can't find it... is there a definitive thread for us newbies who are interested in adjusting the timing of their cruiser? I need pictures, videos, Vanna White...
Thanks in advance!!!
 
SmokingRocks said:
FZJ 80 or FJ 80? There is a pretty big difference in the degree of difficulty between the two.
Click to expand...

Well, there's the newbie coming out- I didn't know there was a difference. I guess I need a pointer to the FZJ80 thread. ;)
 
the FJ 80 was the 91 and 92 and had the older 4 liter engine.

Timing for the FZJ 80 is simple.

  1. Clean off the timing marks (they are on the engine at about the 12 o clock position above the crank pulley)
  2. Let the engine warm up
  3. attach the timing light to the battery and put the probe on the plug wire for cyl 1 (cylinder at the front of the engine)
  4. aim the light at the crank pulley and see where the mark hits
  5. loosen the adjustment bolt on the distributor (I think its on the bottom side if I remember right)
  6. rotate the distributor until you are at roughly 5-7 degrees advanced
  7. Tighten up the distributor adjusting bolt
  8. take off timing light
  9. drive
 
SmokingRocks said:
the FJ 80 was the 91 and 92 and had the older 4 liter engine.

Timing for the FZJ 80 is simple.

  1. Clean off the timing marks (they are on the engine at about the 12 o clock position above the crank pulley)
  2. Let the engine warm up
  3. attach the timing light to the battery and put the probe on the plug wire for cyl 1 (cylinder at the front of the engine)
  4. aim the light at the crank pulley and see where the mark hits
  5. loosen the adjustment bolt on the distributor (I think its on the bottom side if I remember right)
  6. rotate the distributor until you are at roughly 5-7 degrees advanced
  7. Tighten up the distributor adjusting bolt
  8. take off timing light
  9. drive
Click to expand...
Don't you need to jumper the diag port so it doesn't compensate for the timing? From the FSM ('96)
(a) Warm up engine to normal operating temperature.
(b) Shift transmission into ”N” position.
(c) Keep the engine speed at idle.
(d) Using SST, connect terminals TE1 and E1 of DLC1.
SST 09843−18020
(e) Connect a timing light probe to a high−tension cord.
CHECK:
Check ignition timing.
OK:
Ignition timing: 3° BTDC at idle
 
right good catch I forgot you have to use the jumper. 3 degrees is what the book calls for but you can comfortably advance to 7 degrees with no issues. In fact 7 degrees will give you better response at tip in. Personally I think it peps up the engine pretty well.

I've never noticed a difference between park and neutral but if thats what the book says then do it that way.
 
SmokingRocks said:
right good catch I forgot you have to use the jumper. 3 degrees is what the book calls for but you can comfortably advance to 7 degrees with no issues. In fact 7 degrees will give you better response at tip in. Personally I think it peps up the engine pretty well.

I've never noticed a difference between park and neutral but if thats what the book says then do it that way.
Click to expand...
:) Wasn't disputing the advance timing. Seems a lot run 3* and some prefer the + side. Just was remembering there was a step (the jumper) to actually get the timing set before the computer adjusts for you.
 
Do you guys have the link for the clip you're talking about?

Also, is it clear which way to "spin" the distributor? As in, how do I precisely arrive at the degrees indicated? I'm assuming you look at the timing marks while you do it, right?

More questions-
  • I don't want to screw my engine up... is this something that a newb can screw the pooch on?
  • My reason for asking about timing is I'm seriously considering a methanol injection system... any guidance re: timing for meth injection?
PS- thanks for your help!!
 
You rotate the distributor slowly and only a few degrees at a time. All while looking at the timing mark with the timing light.

3* is stock. Some people like to push up to 6 and sometimes higher. If you have an SC you need to stay at 3*. If you have to smog your truck you need to stay at 3*.
 
You are dancing in the red zone at 10 degrees, past 10 you are in danger of pre-detonation. If its a high miler going past 7 degrees is ill advised.
 
Guys- thanks so much for the links and incredibly helpful info. I forgot to check the tech threads for this... apologies!!

I know the SC guys who are running / planning to run meth injection have emphasized the need to adjust the timing, so I'm trying to come up to speed on this topic... and hoping I don't screw something up in the engine itself!
 
I was under the impression it was to adjust the timing.
 
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