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RB25 CAS vs Trigger kit

Nyoom

By Nyoom,
in R Series (R30, R31, R32, R33, R34)

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Nyoom Apprentice

Nyoom

Posted
Posted

Hey guys, first time poster, looking for some advice/help with my R33 S2 gtst.

Pretty sure my CAS just died as the car cranks but wont start. A few weeks ago I took it out to get to my power steering pump and the key on the camshaft side was snapped and floating around.

I managed to realign it when I put the car back together and it ran with no issues. Went down to start it yesterday and the car would not start. Cranked with enough battery voltage to start, ecu came out with code 55 so I have nothing else to suspect other than the CAS being faulty. I took the spark plugs out and they didnt smell like petrol.

Going test with a multimeter to make sure but I had a question before I go ahead and buy a new CAS for $550 (if anyone has one id buy it for cheaper, im located in Sydney).

I have a power fc I have yet to install, and I have not been able to find anywhere a Trigger kit that says it will work or have enough information of their page. Since ill probably have to get a new CAS my thought was why not just upgrade to trigger kit for around the same price, or just a little bit more. I'm not particularly aiming to make power that requires a trigger kit, but aligning the CAS everytime without the key is gonna get annoying. (I will eventually upgrade to tomei cams but am holding off until I finish the rest of the work I need done)

I've had a look at most of the trigger kits out there (PRP, Ross, Hi Octance, etc.) but if anyone has any insight whether any of them will work with a Power FC that would be helpful!

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https://www.sau.com.au/forums/topic/479495-rb25-cas-vs-trigger-kit/
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joshuaho96 Veteran

joshuaho96

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http://www.jimwolftechnology.com/wolfpdf/VG30DETT_CAS_COUPLING_MISALIGNMENT.pdf

You need to repair the CAS regardless if you want to run a PowerFC. Also I would recommend keeping the CAS for its actual purpose, which is a cam sensor. The OEM CAS is great at syncing the engine quickly during cranking as it has distinct home signals for each cylinder.

GTSBoy Grand Master

GTSBoy

Posted
Posted
1 hour ago, joshuaho96 said:

The OEM CAS is great at syncing the engine quickly during cranking as it has distinct home signals for each cylinder.

Yeah, but that's only true for stock type ECUs. The Nissan ECu seems to be able to punch through the jittery noise of the stock CAS at high rpm much better than all other ECUs. All the aftermarket ECUs just suck compared to the factory ECU, perhaps with the PowerFc being halfway between (as I suspect the PFC as being based on a Hitachi ECU anyway). But for anything where there is serious risk of timing jitter killing the engin at high rpm and loads (ie, any serious build), the factory CAS sucks balls and should be replaced with a proper trigger system - which includes a new cam sensor.

joshuaho96 Veteran

joshuaho96

Posted
Posted
11 minutes ago, GTSBoy said:

Yeah, but that's only true for stock type ECUs. The Nissan ECu seems to be able to punch through the jittery noise of the stock CAS at high rpm much better than all other ECUs. All the aftermarket ECUs just suck compared to the factory ECU, perhaps with the PowerFc being halfway between (as I suspect the PFC as being based on a Hitachi ECU anyway). But for anything where there is serious risk of timing jitter killing the engin at high rpm and loads (ie, any serious build), the factory CAS sucks balls and should be replaced with a proper trigger system - which includes a new cam sensor.

I was under the impression that the cam signal is not particularly difficult to parse and could be left alone, it was really just the crank signal that was particularly problematic. Has anyone tried running the OEM cam signal + aftermarket crank trigger?

Nyoom Apprentice

Nyoom

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Posted

Thanks for the info guys.

Just went to test the CAS with a multimeter and all seems fine to me, getting readings on power and the 2 signal wires and can also hear the injectors clicking as I spin the shaft. Kind of at a loss from where to go from here. Am I missing something?

Since it looks like it's a good idea to replace the exhaust cam, which drop in cams should I go for that wouldn't require an immediate tune?

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