Degree 1JZ/2JZ cams

[Sack]

Has anybody done this before on a 1JZ/2JZ before?

I can't get the dial indicator to even touch the bucket as the lobes are in the way, let alone parallel to it. Any of you guys have an idea of how i can get around this as I can't go any further.

Cheers, Brendon

[Oversteer]

Really long thin extension on the di ;)

[S85FI]

What are you trying to do? time it for the belt?

[Sack]

Really long thin extension on the di ;)

Got several, no bingo still


What are you trying to do? time it for the belt?

Zero in the cams to make sure their at the advertised duration at .050" for peak performance.

[S85FI]

Been too long since I pulled something like that a part but isn't the cam dowled so the belt pulley can only determine it's position?

[Yakky Bear]

yeah it is but you can buy adjustable pulleys.

[Sack]

The marks that you line up for the crank and two cams are just to make sure either one isn't 180 out of timing.

I'm degreeing in my 264 cams with adjustable cam gears so that they are performing how BC intended them to.

[uzx83]

Ask Barrett think he did it

[S85FI]

yeah it is but you can buy adjustable pulleys.

Way too long for me. So let me get this right, you get the cam on the rock to find out your maximum lift? and then you would either have to guess your crank gear to determine timing for ignition or do you still do TDC for the crank?

Seems pretty precise considering the cam belt teeth itself would be a factor of error and the belt adjuster itself...:confused:

I just want to turn the key....:)

[Yakky Bear]

http://www.autocarparts.com/images/100/1275_0.jpg

[S85FI]

Clever -
Now I'm going off topic for the intent of this thread - sorry Sack.

So Yakky Bear my understanding is advancing cam would increase power for high rpm, somewhat similar to advancing ignition timing. Giving the engine a spike in HP for a particular rpm and retarding the cam would increase torque but lower hp.

So why not just get a cam with more valve duration and valve lift (if valve lift isn't hitting piston) to have both? Or have I been out of the build scene way toooooo long?

Cheers for the info anyway...

[Rich]

I did mine a few weeks ago on a 2J. Its difficult but you can just get the gauge onto the bucket. Hard to explain. Might be able to give you a hand next week if you are still stuck

[Sack]

Ask Barrett think he did it

He doesn't have a degree wheel yet and his brain will explode trying to work it out haha


Way too long for me. So let me get this right, you get the cam on the rock to find out your maximum lift? and then you would either have to guess your crank gear to determine timing for ignition or do you still do TDC for the crank?

Seems pretty precise considering the cam belt teeth itself would be a factor of error and the belt adjuster itself...:confused:

I just want to turn the key....:)

There is no guessing involved, it's all calculated and you can get all the information off the cam card supplied with the cams. You can factor in the belt in which is roughly .060" if you turn the motor in the opposite direction.

You put crank at no 1 TDC with a pointer pointing to TDC on the degree wheel
Rotate the crank in the direction of rotation until you see the dial indicator move .050" (valve opening .050")
You see where the pointer is now pointing to on the degree wheel, let's say 4deg before TDC
The cam card says it want's 0.050" lift at 1deg after TDC, so you're 3 degrees out and the cam is not operating at peak pefromance.
You then move the crank to have the pointer on 1deg after TDC, then look at how much lift is now reading on the dial indicator, lets say it now reads only .040" lift.
The cam is .010" off so you need to advance the cam until the dial indicator reads .050". If it were reading .060" you would need to retard the cam .010"
So now the cam is operating at peak performance at 1deg after TDC with .050" lift which the cam card states! This also means that any adjustments made to the cam timing are done from this point.


Clever -
Now I'm going off topic for the intent of this thread - sorry Sack.

So Yakky Bear my understanding is advancing cam would increase power for high rpm, somewhat similar to advancing ignition timing. Giving the engine a spike in HP for a particular rpm and retarding the cam would increase torque but lower hp.

So why not just get a cam with more valve duration and valve lift (if valve lift isn't hitting piston) to have both? Or have I been out of the build scene way toooooo long?

Cheers for the info anyway...

Simple cam tuning rules for BOOSTED engines:
Advance intake and exhaust => more low-RPM power, less high-RPM power
Retard intake and exhaust => more high-RPM power, less low-RPM power
Less overlap => lower EGTs, faster turbo spool, less fuel
More overlap => higher EGTs, slower turbo spool, more fuel

You can put whatever cams in you want but they still have to be dialled in properly.


I did mine a few weeks ago on a 2J. Its difficult but you can just get the gauge onto the bucket. Hard to explain. Might be able to give you a hand next week if you are still stuck

Did you put the tip of the indicator right on the edge of the bucket? That's as close as i can get but sometimes it jumps off.