whats base timing on a 97 5VZ-FE??

[stackz]

got a 97 4runner that popped both gaskets. had both heads milled a little and I want to make sure the base timing is correct once I get it all back together.

I know its negligable but I'm a stickler. You short TE/E1 to lock out the ecu right? how do you adjust the base timing after this and what should it be set to?

I mean its COP but it should have a way to be adjusted...

 

[Jetboy]

I assume you're talking spark timing. I don't know much about the 5vz timing. My guess is that the spark curve is learned by advancing until the knock sensor signals it to back off then it recalibrates from there. IIRC that's how Honda does it. I don't know that I've ever looked into how Toyota does it. I don't have any idea how you could manually set the timing curve without a stand alone system or some type of signal interrupt.

It should not change with head work. Crank position is pulled off the crank. TDC doesn't change. Nor should timing. Each valve system could be off by a fraction of a degree, but that still wouldn't change the appropriate spark timing as compression max time is dictated by crank position not valve timing.

 

[stackz]

um I think we're not on the same page. I don't want to change the timing tables...

I want to make sure I have the base timing set properly. say...when I put the heads back on and line everything up and then rotate the engine...because the heads are shaved, after rotating the engine the cams are slightly off while the crank pulley is at TDC....this means the timing will be slightly advanced or retarded.

thus, you lock out the ecu and then adjust the base timing via the crank pulley (there's a reason it has a slot and then the timing cover has different numbers on it) as it will likely be running either advanced/retarded. advanced and it will run hotter, retarded and it will be low on power...as a basic approach. but for emission purposes, it can mean a pass/fail.

I want to know what the base timing should be and how to properly adjust it without the ecu advance in effect is what I'm getting at.

think...base timing on a ford 5.0. you pull the spout out and set base timing to 10* BTC by rotating the distributor..

hell you can even do this with the ford 4.6 which is COP. has to be a way for the factory to properly set base timing.

 

[snobdds]

There is no way to adjust timing...all ECU controled.

The only way I know is to make sure the marks on the belt line up with each cam pully and the crank. Then the ECU takes it from there with input from the signal sensors...

 

[stackz]

well ok then, and away I go.

this will definitely be a first for me. even with distributorless ignitions on fords you could still lock out the ecu and set the base timing. guess toyota doesnt want us to have that option lol.

 

[snobdds]

It just means the timing is set at TDC or 0*. Therefore there is no need to lock out the ECU to get to a base timing. It's set by default...one could argue Toyota took the best approach to this then say Ford.

How much did you get your head shaved down?

 

[Jetboy]

I think I might be able to explain a little better what my thoughts are on why it's not adjustable.

The valve timing is adjustable to ensure it matches the crank timing. So the valves open an close in proper relation to the crank shaft and piston position. That's why there is an adjustment available on the cam shaft drive gear. You probably need to do this after head milling.

The spark timing is set based on the piston position - which is measured based on the rotation of the crank shaft. The timing of the camshafts should be adjusted to the crank shaft. The spark is based also on crank shaft. So long as your cams are adjusted properly to the crank, the spark should be correct from the ECU in relation to both the crank and the cams that have been adjusted to the crank.

If there was a situation where the cams were not in proper timing with the crank, you'd still want the spark to be set by the crank timing not the camshaft timing. For example if your cams were 2 degrees advanced, you don't want your spark to be 2 degrees advanced because you'd be too far ahead of the piston reaching TDC and you'd get a ping. OTOH if your cams are 2 degrees advanced and spark is on time in relation to piston motion, you probably won't notice the difference. In one situation you could damage your engine, the other you might lose 5hp.

If you're trying to set the cam timing to ensure it's properly rotating with the crank, I think the FSM has the procedure for that. I'm guessing google might turn up a 'how to' as well. I've done two timing belts on 5vz's but that as far as I've gotten. Never gone into adjusting the cam timing beyond putting it back the way it was.

 

[mmml4]

Ignition timing is 8 to 12 degrees BTDC with TE1 and E1 jumped.

 

[stackz]

Ignition timing is 8 to 12 degrees BTDC with TE1 and E1 jumped.

there we go. now, with te1/e1 jumped, how do you adjust the timing?

also, anyone know if the head bolts are re-useable or torque/yield?

anyone know the torque specs on the head bolts and intake bolts? also the came sprocket bolts??

I'm in the process of searching but figured I'd ask anyway.

 

[snobdds]

there we go. now, with te1/e1 jumped, how do you adjust the timing?

also, anyone know if the head bolts are re-useable or torque/yield?

anyone know the torque specs on the head bolts and intake bolts? also the came sprocket bolts??

I'm in the process of searching but figured I'd ask anyway.

He doesn't know what he's talking about. Jumping TE1 and E1 was used for 85-95 Toyota 22RE and 3VZE engines. That was when there was no ODBII to interface with.

Like I said, there is no way to "lock-out" the computer to set a base timing. It is set at 0* or TDC. Period. Then the computer takes it from there...

 

[mmml4]

He doesn't know what he's talking about. Jumping TE1 and E1 was used for 85-95 Toyota 22RE and 3VZE engines. That was when there was no ODBII to interface with.

Like I said, there is no way to "lock-out" the computer to set a base timing. It is set at 0* or TDC. Period. Then the computer takes it from there...

That came right out of my 99 FSM .

 

[mmml4]

there we go. now, with te1/e1 jumped, how do you adjust the timing?

also, anyone know if the head bolts are re-useable or torque/yield?

anyone know the torque specs on the head bolts and intake bolts? also the came sprocket bolts??

I'm in the process of searching but figured I'd ask anyway.

Head bolts are reusable. They are torqued in a sequence to 25 lbs. and then they are torqued in 90 degree increments two times. I can post a pic if you like.

Intake plenum bolts torque 13 lbs.

Camshaft pulley bolts torque 81 lbs.

The FSM says nothing about adjusting the timing just checking it.

 

[snobdds]

That came right out of my 99 FSM .

I bet, right next to the part that says to turn your coil packs to adjust timing, right...?

It's all computer controlled, you can't manually change the timing on a 5vz-fe. The only way to do it is to add a piggy back system, but leave that to the professionals.

 

[mmml4]

I didn't say it could be adjusted, only checked and that's how the FSM says do it.

 

[mmml4]

I bet, right next to the part that says to turn your coil packs to adjust timing, right...?

It's all computer controlled, you can't manually change the timing on a 5vz-fe. The only way to do it is to add a piggy back system, but leave that to the professionals.

GTFU