Has anyone advanced the timing on 1FZ-FE?

[BillyGoatMTB]

I run about 7 and 1/2° advanced timing

It's a safe, sweet spot, I'm geared 488 with 35s

I've not heard good things for longevity above 9° timing, and the timing advancement doesn't make that huge of a difference. It's just a nice smoother throttle response and overall experience with the 1fz.

Putting time and effort into re-gearing was an absolute number. One game changer!

I couldn't imagine trying to drive around with stock gears and 37s. That sounds like a nightmare.

 

[TYM4FUN]

Gonna bump an older thread here... regarding timing. I recently had to smog my 94, and while it passed emissions, evap etc. the tech came back and said he failed it because the timing was set at 15*

He set it back to the factory recommended 3* but advised me it would run more sluggish. I had him mark the dist where it was previously set just in case i want to bring it back to its presmog setting.
On the drive home I did notice it was running like a dogggggggg. I mean, 37's on stock gears its already a dog, but this was awful. I wasn't aware my timing was set so advanced.

So, finding this thread and reading that advancement is common, but 15* seems like a pretty aggressive number! However I never heard any pinging, knocking or other odd noises, and I usually mid grade gas.

Question is... do I set it back to the previous setting?

For good measure, have it verified by another person if you are unable. There is always the possibility the man did not have the terminal grounded properly and it is now overly retarded.

 

[BillyGoatMTB]

For good measure, have it verified by another person if you are unable. There is always the possibility the man did not have the terminal grounded properly and it is now overly retarded.

Great point. Whoever checked the timing might not have correctly performed the reading with the pins connected.

Invest in a timing gun.

 

[CharlieS]

Great point. Whoever checked the timing might not have correctly performed the reading with the pins connected.

Invest in a timing gun.

100% they didn't jump the DLC pins!

 

[FFDawson]

Thanks for the input. After reading this thread that was my first thought, that they didn't jump the pins... so I placed a call the very next morning... I spoke to the tech and even before I mentioned the pins he cut me off and said "and yes I checked the timing in test mode with the pins jumped" so I kind of took his word for it. Either way, I do have a timing light, so I'll double check tomorrow.

 

[FFDawson]

And come to think of it, when I had the rig baselined at Valley Hybrids, they replaced the distributor and cap, so I'm confident they had the timing set for ideal power/efficiency.

Smog is the worst.

 

[flintknapper]

I would definitely advance the timing again but I wouldn't take it to 15°.

I've run mine at 7° btc for the last 20 years with no ill effects and feel that it is ideal for MY set up (33" tires, stock gearing).

There is only so much you can/should do with ignition timing. For improved performance (on 37's) re-gearing would be your only solution (with factory engine).

 

[FFDawson]

Oh I'm fully aware of the need to regear. I've got a built t case with the 10% over and under drive gears, a set of rci axles and manual hubs sitting on the shelf waiting for install. Just saving up for the f/r diff gears. I'm not suggesting I try to solve the acceleration problem with extreme timing... I just was surprised to hear from the smog tech that I was set at 15*, and wondering whether or not I should set it back to that setting. It was running and driving perfectly prior to the smog tech retarding the timing.

 

[mudgudgeon]

I'm with the others. Check and verify timing for yourself.
I've run mine at around 7-10⁰ for quite side time. Definitely not responsive overall.

10⁰ seems to be the practical limit, less for some engines.

There was a good write up on timing advance in the old LCOOL Technical pages, unfortunately that site is gone.

It takes literal minutes to tweak the timing. If you have to go to 3⁰, and back for a smog test, it ain't the end of the world.

 

[FFDawson]

Ok this is odd... I placed the truck in service mode, properly jumping e1 and te1, confirmed by the binking CEL on the dash, then re-set timing to 3*. Shut the truck off and removed jumper, and re-started. Timing remained at 3*... I re-set jumper and advanced timing to 8*, removed jumper and timing stayed at 8*...

It is my understanding that setting the truck in "service mode" should alter the timing right? It doesn't seem to make a difference in the timing whether the truck's in service mode or not. I set it to 8* and then went for a test drive and it feels great, like it was prior to all of this... perhaps even a tad bit smoother acceleration.

So am I missing something in the Service mode application?

 

[mudgudgeon]

Ok this is odd... I placed the truck in service mode, properly jumping e1 and te1, confirmed by the binking CEL on the dash, then re-set timing to 3*. Shut the truck off and removed jumper, and re-started. Timing remained at 3*... I re-set jumper and advanced timing to 8*, removed jumper and timing stayed at 8*...

It is my understanding that setting the truck in "service mode" should alter the timing right? It doesn't seem to make a difference in the timing whether the truck's in service mode or not. I set it to 8* and then went for a test drive and it feels great, like it was prior to all of this... perhaps even a tad bit smoother acceleration.

So am I missing something in the Service mode application?

In service mode, the timing stays static. No change by the ECU.
IME, the timing jumps all over the place if you don't have it in service mode. In service mode, it won't fluctuate, it should be steady.

 

[80ways]

There was a good write up on timing advance in the old LCOOL Technical pages, unfortunately that site is gone

I think that this is the LCOOL info you are referring to... if not, my apologies!

Ignition timing for the 1FZ-FE 4500cc petrol motor
This modification deviates from the manufacturer's specifications. This is not endorsed by Toyota. You are liable for anything and everything to do with your 80 Series if you modify it.

The twin cam 4500cc 80 Series motor has quite a conservative factory ignition timing spec. Probably due to the fact that they are prone to pinging without the "mechanically barren" driver knowing it. They are built with a knock sensor which retards the ignition timing when it logs a number of knocks in quick succession. The engine ECU does not keep a log of knocking (as opposed to almost anything else to do with the vehicle).

The ECU adjusts the ignition advance relative to the base timing given a number of inputs from other sensors feeding it information. It however has no concept of total advance. This means that with additional advance, the ignition timing retains the additional advance right through the rev range.

You do have the ability to gain some power, especially off the mark and at lower revs as well as better fuel economy by advancing the ignition timing. The quality of fuel however plays an important role in how successful this mod is.

All you will need is a paper clip, an ignition timing light and a 12mm spanner.

Firstly, make sure the engine's at normal operating temperature and that the A/C is off. Connect the timing light to plug lead No 1 and check the ignition timing. It's probably around 10 deg BTDC under normal ECU control.

Switch the engine off, remove the key and locate the ECU service plug. Using the bent paper clip, short out the E1 and TE1 terminals. Confirm that the contact is made by turning the ignition on and on most models, the engine check dash lamp will blink.

Start the engine and check ignition timing (now in service mode). The standard timing is 3deg BTDC and is marked on the timing chain cover. If the timing is unchanged from when you previously checked (around 10 deg) it means that the terminals E1 and TE1 have not be shorted.

Loosen the distributor bolt and advance the timing to 6 or 7 deg (Australian spec. Maybe the same for other countries). Tighten the distributor bolt and check the timing again.

Turn the engine off, remove the key and remove the paper clip. Check the ignition timing again (now under ECU control) and it should read anywhere between 0deg - 16deg BTDC.

Road test paying particular attention to any knocking sounds from the motor with the accelerator floored at ~2,000 rpm. If it does knock, then retard the timing. Knocking or pinging is often affected by the quality of petrol (gas), altitude and/or carbon deposits in the combustion chamber. If it doesn't ping, you can experiment with more advance, however anything over 10 deg BTDC is considered to be a lot for this motor.

If the ignition is over advanced and the knock sensor signals that the timing is to be retarded, then you will actually lose on performance (and economy) since it retards in large steps.

Each engine is different as are fuels from different suppliers. Fuels also vary in quality throughout the year.

When well adjusted, you'll notice the extra power.