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  #1  
Old July 12th, 2018, 06:55
RCP Phx RCP Phx is offline
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Camshaft position sensor ?

On a 2000 does it really do anything? I'm assuming the initial timing, the advance curve, and the total timing are all controlled by the ECU.
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Old July 12th, 2018, 08:58
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Re: Camshaft position sensor ?

The crankshaft position sensor gives the ECU the information about where in the revolution the crankshaft is at. The camshaft position sensor tells the ECU where in the four strokes the engine/cam is at. In other words. The #1 cylinder does not fire at TDC on every rotation, but every other rotation.

Once that is established, the ECU can easily keep track of it for the duration the engine is on. On a Renix, if the cam sensor is not working, it randomly picks one and tries it. If it starts, all is fine. If it does not, you try again until it starts.
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Old July 12th, 2018, 10:19
RCP Phx RCP Phx is offline
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Re: Camshaft position sensor ?

On the 2000-01's the coil rail does fire every revolution!
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Old July 12th, 2018, 11:23
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Re: Camshaft position sensor ?

OK the coil may fire the plug, but the same synchronization occurs for the injector pulses.
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Old July 12th, 2018, 12:30
RCP Phx RCP Phx is offline
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Re: Camshaft position sensor ?

I realize that, but what would happen if I changed it say +/- 5* ? Would The ECU automatically compensate? I'm looking to test more timing?
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Old July 12th, 2018, 16:15
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Re: Camshaft position sensor ?

It would affect injector timing, not ignition timing.

You'd want to move the crank position sensor.
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Old July 15th, 2018, 07:16
Jeep Driver Jeep Driver is offline
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Re: Camshaft position sensor ?

Quote:
Originally Posted by cal View Post
It would affect injector timing, not ignition timing.

You'd want to move the crank position sensor.
That's correct.

Valve timing, ignition timing, injector timing, all are completely independent.

I just had this argument with the so-called mods on another site, regarding advancing valve timing and ignition timing..........one has nothing to do with the other, advancing valve timing does not advance ignition timing. Actually, what you are doing is retarding injector timing by 2 degrees in relationship to valve timing....if you are doing anything at all.

This is the lock-box that AMC/Chrysler locked you in.

Everyone loves to talk performance..........if you cannot adjust your timing parameters, no performance, and that's where everyone is stuck.
Jeep people cannot get this through there thick heads.


You want a solution? Here-

I have a high-end machine shop making a one-off part for me now, I've seen what they do with a water-jet, gears, mind blowing precision.

Have the tone ring machined off a new flywheel. Have a machine shop cut you a new tone ring. Just as you can remove and replace a starter ring gear, you can do the same with the tone ring.
Flywheel and tone ring will need to be degreed and marked.
With the engine on an engine dyno, begin the long process of timing the ring.
First one will cost you about $10K.

Then spend another $$$$$ finding someone to develop a programmable ECU, or a remap or flashed ECU.

Until then.........you guys nibble round the edges. And even then, the 4.0 has it's own mechanical constraints.
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Old July 15th, 2018, 08:33
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Re: Camshaft position sensor ?

Well, that's a theory.

It's a lot easier to move the CPS on it's mounts. Or on a late model adjust timing in the ECU.


Both of which are regularly done.
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Old July 15th, 2018, 08:40
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Re: Camshaft position sensor ?

The iginition timing tables can be changed in anything from 91 and newer, and if I really cared enough about the renix, I could probably make it happen for those guys as well. But it's easier to just get the renix high altitude CPS and call it good.
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  #10  
Old July 15th, 2018, 08:40
RCP Phx RCP Phx is offline
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Re: Camshaft position sensor ?

As usual your on Pluto while the rest of us reside on Earth!

There would be no reason to do all that when a adjustment for the crank sensor could be made for pocket change.
You can only change the valve timing with offset gears( I already have that).
The ECU still "mapped" regarding the readings that it gets from the sensors.
Those maps can easily be changed "ALOT" cheaper thru Chris T or Flyan Ryan.
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Old July 15th, 2018, 08:53
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Re: Camshaft position sensor ?

Quote:
Originally Posted by RCP Phx View Post
As usual your on Pluto while the rest of us reside on Earth!

There would be no reason to do all that when a adjustment for the crank sensor could be made for pocket change.
You can only change the valve timing with offset gears( I already have that).
The ECU still "mapped" regarding the readings that it gets from the sensors.
Those maps can easily be changed "ALOT" cheaper thru Chris T or Flyan Ryan.
F'ing bullshit.

What's a lot?

1 degree with CPS??


This discussion has taken place over the years by many, look back on the stroker sites, many have tried to fool the ECU to advance timing.

And if it were so easy, you'd just do it........instead you are asking how to do it.


Again, thick heads.
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Old July 15th, 2018, 11:52
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Re: Camshaft position sensor ?

+/- 5* by CPS. Or you can break the tab and rotate the distributor.

AMC actually sold CPS's that were advanced 5* as an option.
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Old July 15th, 2018, 11:53
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Re: Camshaft position sensor ?

(and I have been just doing it in my strokers for years)
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Old July 15th, 2018, 12:56
RCP Phx RCP Phx is offline
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Re: Camshaft position sensor ?

So can I assume correctly that with exception of being able to "tweak" a few components, that the "proper" adjustment of different parameters (such as widening the ign timing curve) can only be done thru the ECU?
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Old July 15th, 2018, 13:24
Jeep Driver Jeep Driver is offline
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Re: Camshaft position sensor ?

Quote:
Originally Posted by RCP Phx View Post
So can I assume correctly that with exception of being able to "tweak" a few components, that the "proper" adjustment of different parameters (such as widening the ign timing curve) can only be done thru the ECU?
Yep.

And once you accept this fact..................


I'm only posting here because, and not argue specifics, I read and read and read all the stroker's posts, just how badass and soforth.


Then right back to the same questions- how do I get more.

You guys are never satisfied, ever. 4.0s leave you wanting.

Well, for all your money and effort......you are half way to a SBC...........lol


That's where I'm going with mine......I got off the merry-go-round long ago.
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