How To Adjust Timing in the FJ80

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That's where we are getting stymied. Don't know how fast and how far the ECU pulls timing back when the knock sensors are triggered. I know that on several hyway hill climbs last Saturday I was full into the throttle at 3500 ish rpm and 85? Mph and my SG showed my ignition was only advanced to 4 degrees. I am used to a lot more advance back in the carved Chevy small block days! John
 
Landseer said:
Anyone know how far you can advance the timing if you run a higher octane?
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From my personal experience you can comfortably go to 8 degrees with regular fuel. I have mine at 10 degrees and I still don't hear any ping with regular but I run premium anyways just in case. There is a very slight power gain compare to 6 degrees with regular fuel.
 
SmokingRocks said:
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.
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My question is how high can you go with premium fuel, I know 10 degrees is no issue at all so I'm guess you can go to 12 or 14 with premium fuel?
 
Yes, lots of confusion and people throwing numbers back and forth in this thread without clarifying.

Retro is Right
NLXTACY is Right.
Qball and Smokingrocks are Right

But all of them need to be clarified.

Retro is absolutely right in the method.
NLXTACY is right that with a SC'er until you have both meth/water injection and a way to measure knock you want to be at 3*
Oball and Smokingrocks are right that a stock naturally aspirated truck running more premium fuel will probably benefit from a little extra timing.

Iceaxe,

I suggest you go ahead and get the fancy paper clip, get a timing light and familiarize yourself with the process. Read up on why you are doing what you are doing and why you can add some additional timing with water/meth. But then also realize the issues you will face if you are out in the middle of nowhere and find yourself without meth because you used it all up to get there.

Just my $0.02.
 
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You don't need to run premium fuel to advance timing to 7 degrees. Unless you have tons of carbon build up there won't be a problem at 7 BTDC and 85 octane.

Now @Qball I suppose you could experiment with this if you had an engine you didn't care to potentially destroy. You could run a tank of 85 just below pinging (probably 10-12 BTDC) then you could empty the tank and run 93 then readjust timing to right before pinging. Pretty unscientific but that would be the back woods way of doing it I suppose.
 
yes hence my statement:

"I suppose you could experiment with this if you had an engine you didn't care to potentially destroy.""that would be the back woods way of doing it"

The right way to do it involves compression testing to identify your engines specific ratio at its age. Then using math and known properties to determine when detonation would happen without the spark. You will basically have to engineer your own solution and hope you did it right.

Or you could just advance to 7 degrees (unless you are supercharged) because plenty of members and mechanics have and feel fine about it. If your engine goes then rebuild or swap something more interesting in.
 
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When the ECM retards timing it does so in large increments which could nullify any gains from manually advancing beyond a reasonable setting. Timing at 6 to 7 BTDC is about the limit in my opinion on a normally aspirated 1FZ-FE with regular unleaded fuel.
 
scottryana said:
Yes, lots of confusion and people throwing numbers back and forth in this thread without clarifying.

Retro is Right
NLXTACY is Right.
Oball and Smokingrocks are Right

But all of them need to be clarified.

Retro is absolutely right in the method.
NLXTACY is right that with a SC'er until you have both meth/water injection and a way to measure knock you want to be at 3*
Oball and Smokingrocks are right that a stock naturally aspirated truck running more premium fuel will probably benefit from a little extra timing.

Iceaxe,

I suggest you go ahead and get the fancy paper clip, get a timing light and familiarize yourself with the process. Read up on why you are doing what you are doing and why you can add some additional timing with water/meth. But then also realize the issues you will face if you are out in the middle of nowhere and find yourself without meth because you used it all up to get there.

Just my $0.02.
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Scottryana, circling back to this thread (distracted with work)... Copy the above... What I'm trying to understand here is whether you MUST go with stock timing if you have an SC + smaller pulley / more boost + meth injection setup....

Regarding access to an ability to monitor what whether the knock sensor is being tripped off, does anyone know of a product that will enable monitoring of this?
 
No there is nothing that says you must... The determinants are going to be the temperature where you live, the humidity where you live and at what altitude you live.

I would start with stock timing for sure. I certainly wouldn't turn the timing up to the point of knock when the truck is NA and then throw a SC on it.

They do make knock sensing devices but most are not meant for permanent use. They are like knock ears that you can wear. You input the size of the bore since it is what correlates with the frequency of the knock and you can listen for it.

There are a few stand alone knock detectors like Knock Link, J and S safeguard, etc.

Iceaxe said:
Scottryana, circling back to this thread (distracted with work)... Copy the above... What I'm trying to understand here is whether you MUST go with stock timing if you have an SC + smaller pulley / more boost + meth injection setup....

Regarding access to an ability to monitor what whether the knock sensor is being tripped off, does anyone know of a product that will enable monitoring of this?
Click to expand...
 
scottryana said:
No there is nothing that says you must... The determinants are going to be the temperature where you live, the humidity where you live and at what altitude you live.

I would start with stock timing for sure. I certainly wouldn't turn the timing up to the point of knock when the truck is NA and then throw a SC on it.

They do make knock sensing devices but most are not meant for permanent use. They are like knock ears that you can wear. You input the size of the bore since it is what correlates with the frequency of the knock and you can listen for it.

There are a few stand alone knock detectors like Knock Link, J and S safeguard, etc.
Click to expand...
scottryana said:
No there is nothing that says you must... The determinants are going to be the temperature where you live, the humidity where you live and at what altitude you live.

I would start with stock timing for sure. I certainly wouldn't turn the timing up to the point of knock when the truck is NA and then throw a SC on it.

They do make knock sensing devices but most are not meant for permanent use. They are like knock ears that you can wear. You input the size of the bore since it is what correlates with the frequency of the knock and you can listen for it.

There are a few stand alone knock detectors like Knock Link, J and S safeguard, etc.
Click to expand...

Thanks Scott... may I ask how you do it? Do you use a knock detector when you are adjusting timing?
 
When I do it and am setting up my tune on the dyno, we use knock ears and then dial back about 2 degrees across the entire range. A little different since I am using a stand alone and am in control of all the ignition timing. But I would treat it the same way. Start low, add timing until you have knock and then dial base timing back 2-3 degrees.
 
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