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Apparently you dont have you. A while back i read that for us 2jz guys, the crank sensor is responsible for timing and the inlet cam sensor is just referenced for where you are in the cycle. Maybe someone can confirm that before people go out and mess with their timing tables.
I will find out soon. Im going to move the intake cam and check base timing and see if it moves.
 

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I will find out soon. Im going to move the intake cam and check base timing and see if it moves.
well since the multi tooth on the crank trigger dosent have a missing tooth to reference for and use the cam trigger as a pure home signal then it cant know exact where it is in the cycle,so in 2jz case the cam trigger both give trigger angle and works as a home signal and use the crank wheel to count cycle,but the small changes you do on the camgear might not allways inflect the ignition readings, but just to be sure you should allways synk your ignition after messing with intake camgears.
//M
 

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I just redegreed my S1 cams after a tear down. I used a new, but same stock head gasket and the head and deck were untouched. Rechecking TDC on the balancer still showed it was close to 1/2* advanced for true tdc. Heres what I found on the degreeing. On initial setup, I ran the dial indicator vertical. I then helped a buddy with his 1j, and made the C shaped adapter and got acual valve angle. So I did mine that way last night.

Vertical I found intake cam to be +2.5, and exhaust to +4.
Same angle as valve, the same setup shows intake cam +1, and exahaust cam to be +2.
 

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I will find out soon. Im going to move the intake cam and check base timing and see if it moves.
Silver z, please post your results when you do this, so we can find out once and for all whether inlet cam advance really does translate into base timing advance. I have it in my head that each 1deg of inlet cam advance translates to 2deg of ignition timing advance, and would love to know if that's true.
 

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Silver z, please post your results when you do this, so we can find out once and for all whether inlet cam advance really does translate into base timing advance. I have it in my head that each 1deg of inlet cam advance translates to 2deg of ignition timing advance, and would love to know if that's true.
I will for sure, been finishing up projects for others so my car has been on the back burner other than to just drive it :)
Tuesday I should have an answer.
 

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Discussion Starter · #66 ·
I just redegreed my S1 cams after a tear down. I used a new, but same stock head gasket and the head and deck were untouched. Rechecking TDC on the balancer still showed it was close to 1/2* advanced for true tdc. Heres what I found on the degreeing. On initial setup, I ran the dial indicator vertical. I then helped a buddy with his 1j, and made the C shaped adapter and got acual valve angle. So I did mine that way last night.

Vertical I found intake cam to be +2.5, and exhaust to +4.
Same angle as valve, the same setup shows intake cam +1, and exahaust cam to be +2.
Same angle as valve is definitely what you want. The way to verify that it's all good, either straight on or with the C-shaped adapter, is to check valve open and closing times for total duration. If it's less than specified, you were at a slight angle still. If it's bang on, you're good to go!
 

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Same angle as valve is definitely what you want. The way to verify that it's all good, either straight on or with the C-shaped adapter, is to check valve open and closing times for total duration. If it's less than specified, you were at a slight angle still. If it's bang on, you're good to go!
closing event were less than a degree off so i locked them down. I did add a degree to the exhaust to help with a little spool tho. Ill head back to the dyno soon and work out the final details there.
 

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Silver z, please post your results when you do this, so we can find out once and for all whether inlet cam advance really does translate into base timing advance. I have it in my head that each 1deg of inlet cam advance translates to 2deg of ignition timing advance, and would love to know if that's true.
like we allready say it does inflect,but not so very much, but 2 deg on a aggresive igntition from start and regular fuel and then you go from say a retarded camgear setting to advance then 2deg can ruin your engine, on a e85 car like my own +-2 degree on a good tune engine is no problem,but allways check base timing when degreeing intake, just for fun i went from +2 to -2 just for a check on the intake and that ended up in around 1 1/2 deg wrong reading,
 

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Discussion Starter · #69 ·
closing event were less than a degree off so i locked them down. I did add a degree to the exhaust to help with a little spool tho. Ill head back to the dyno soon and work out the final details there.
What about opening event though? Either one can be bang on with the other being way off. Knowing the total duration is what clues you in to the problem. If your dial wasn't straight on, the effect is a shorter total duration. It almost tricked me until I double checked both events the next day and noticed the duration was shorter than specified. You can can actually get the timing right even with that short duration if you do a ratio (specified duration to measured duration, and degrees for both) and go from there.
 

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How close to the cam card did you end up at? I had mine degrees to the cam card exactly and it's perfect. Greg did his home work!
 

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My opening events were spot on after cam adjustment, and the closing events were less than a degree off (I don't remember which way, it was late when I was finishing up with the project). I told my buddy, its within a degree, F it, lets button this up and start the wiring!

I was just sharing my results of the vertical dial vs a dial that is angled with the valve, and the importancy of it.

I used a pc of bent tig rod, superglued it to the shaft then use a pcs of shrink tube. Its pretty solid.
 

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Hi silver z, any luck :)?
Yeah sorry been real busy.
Im sure everyone will have different results, with my head being decked twice and the block once im sure changes things aswell. When I moved the intake cam 2* it moved my timing about 1/2* so not much. I have a buddy that's finishing up his build and I want to do the same thing with his to see the difference.
 

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Silver z, thank you for the feedback! I'm looking forward to hearing what the testing on your buddy's car shows. I'll try and find time to test my own setup with a timing light as a data point as well.
 

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I was able to just check mine. My intake was at 2.5* with timing offset at 5.5*, I redid them and now the intake is just over 1* and I had to move my timing to 4.5* offset.
 

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Hi Nathan, thanks for this data. Just so I'm not misunderstanding you, I read this as saying your initial intake cam advance of 2.5deg yielded a timing advance on top of the base timing of 5.5deg; and once you had changed it to 1deg inlet cam advance, your ignition timing was advanced 4.5deg? Can I ask what prompted you to re-do the inlet cam advance - were you degreeing the cam to spec? Also, can you provide some information on your setup - displacement, any decking of the block/head, basically anything that might be relevant to ignition timing related to the inlet cam? Thanks a lot again :)
 

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On my initial cam install, the dial indicator was not perpendicular to the lifter. I had to tear the engine down from a spun bearing so I took the time to make the proper attachment to the dial indicator and redegreed the cams.

Im using megasquirt for engine management and its the timing offset needed on the cam input compared to locked out timing. So its not anything above or below base timing, its the location of the cam tooth in relation to tdc.

My block and head were only machined for proper mls install. I never asked the amount taken off. And Im using the stock gte gasket.

This is a .020 Overbore 2jz setup with S1 cams and Titan gears.

And after working with AEM on this same motor, whenever the intake cam is moved timing needs to be reverified
 

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hello..back from the dead..but i need your input and help
i am running t4 spa manifold with 6266 turbo and free flow 3.5'' catless exhaust
i degreed my motor to cam card spec but the valve lash was not set to zero
i ended with 4 degrees exhaust(1 mark = 2 mark crank degree) /1.5 advance on intake cam
my egt is always high and my manifold is glowing red..i haven't put the car on the dyno but i am listening to knock and reading spark plugs and afr at 10.9-11 all over the rpm range
could i need to retard the exhaust and intake to reduce overalp a little bit ?
 

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I would pose this question about the EGT to Greg if I were you. Give him a call or email him. He answers emails pretty quick.
Your valve lash should be 0.012" on the exhaust side and 0.010" on the intake btw. Also my cams are set on the third mark.


S2 cam illustrated below
 
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