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stony

RB CAS drive gear replacement info.

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Well i found out last night my CAS sensor key on the cam side was broken off.

 

I was thinking i should be able to just set the engine at TDC and set the cas sensor in. i can see the part the broke off so i just need to line up the 2. and be very careful it goes in the right way.

 

If Anyone has a motor out that they can verify this for me? set it a tdc and take the cas sensor off and take a pic of the cam key. i would extremely appreciate it.

 

Im having a feeling this is why my car wasn't running right. i originally suspected the altitude and i need to tune it. but if this has been broke for a while and i installed it a tooth or 2 off that would explain all the popping and idling problems.

 

Or if there is an easier way i'm all ears.

 

Not going to swap cams at this point damn things are way too expensive.

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Hi Stony

mate this happens because the cas is not in it right spot , with no back lash , it happens when people run the engine with the top cover of so you can see the belt , .. when it happens you need to replace the cam , with out the tab the timing has to much scatter and the timing will be all over the place ,,,

pmc

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Hi Stony

mate this happens because the cas is not in it right spot , with no back lash , it happens when people run the engine with the top cover of so you can see the belt , .. when it happens you need to replace the cam , with out the tab the timing has to much scatter and the timing will be all over the place ,,,

pmc

 

 

PMC<

 

If i swap cams to a more mild cam ( currently both are 280 dur 10mm lift cams) where will i loose my power? just top end hi rpm stuff. i don't intend to turn the motor past 9500 rpm so i'm guessing it wouldn't hurt to go to a milder cam.

 

any suggestions. i would like to gain back some torque in the lower rpm range.

 

 

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Just started understanding the instructions for the cas gear replacement. looks pretty striaghforward. going to order it in the AM. will do a writeup on how it goes.

 

In the pics it looked like the old part coming out was threaded and the new part was not. thats what i didnt understand. The treads i saw in the pic were from the bolt that was threaded all the way thru and pushthe gear out of teh cam. :huh:

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Well i got my replacement cas drive gear and installed it tonight. it wasn't quite as easy as the instructions depicted. If anyone tries this i highly suggest going with a size larger bolt then the one recommended in the instructions. I broke it in the first attempt. once i went to a my HD bolt it came right out. the one that came out of my HKS cas was a tad longer then the replacement. so when i was drilling i was really concerned i was drilling into the cam. but it turned out it was a 3-4 mm longer and when i finally realized that i finished drilling all the way thru and tapping it as the instructions stated. here is a pic of what i eventually got out. i was a little off center so it kinda destroyed the smaller part of the gear but had plenty of material in the larger pressed in part.

 

casdrivegear.jpg

 

Now just need to get my new Cas sensor and attempt the AEM cas wheel swap again cool.gif

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Jwt sells these and it's not super easy to do it but it might be cheaper than the cam itself.

 

az320-caspn_WEB.jpg

 

http://www.jimwolfte....asp?PartID=500

 

FYI, either vg30 install this drive gear different or the instructions you download to do this replacement are wrong. I have been trying to start my car for 3 days now. Finally brought over some AEM guys and we figured out for some reason my coil phasing was 180 out. Once we redid the phasing, the car started right up. It wasn't till i cam across a pic on the internet of a rb26 cam did I realize that even after very closely following the instruction for the gear install, I installed it backwards (180 degrees out). Now either the VG30 install is different or the instruction are wrong.

 

I did specifically ask the sales rep when i ordered this if there was any difference between the vg and the rb and he said no they are identical.

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az320-caspn_WEB.jpg

 

Be aware that if you do this on a rb motor the instruction for the VG will not work.... well they will but it will put your timing 180 degress out. I guess the VG motor cas drive gear is installed with the half

round extension positioned on the left (9:00 o’clock if the

cam dowel is at 12 o’clock) and the straight edge aligning

with the middle of the cam dowel pin. Where a rb motor needs to be installed with the half

round extension positioned on the right (3:00 o’clock if the

cam dowel is at 12 o’clock) and the straight edge aligning

with the middle of the cam dowel pin.

 

I found this out the hard way and spent 3 days troubleshooting why my damn car wouldnt start. The repeated attempts at starting also fouled my iridium plugs so when we first tried the 180 degree fix it still didnt start. but once we got down to if has to be timing we put new plugs in and it started right up. Hope this helps someone out someday ;>

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That makes sense, when I thought I had a faulty CAS on my RB20 I installed a VG30 CAS and while it physically fit, the car would not start.

 

Stony if I shipped the VG30 CAS to you, would you try to see if it would with your modified cam? If so, it gives us RB guys another (albeit more work) option. If it works, I may just do it since the Z32 CAS is easier to find than the RB series CAS.

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HAHA called jim wolf today to discuss the reverse timing thing from the VG instructions and they said yes the VG is opposite. I was like why did you tell my it was the same for the RB. He said the pin itself is the same for the RB VG and CA. but for the RB and CA the pin has to be installed opposite the instructions. They also assumed that a person would look at the old one before removal and re-install the same way.... hmm i guess that's fair enough. i suggested they put a little note on their website to let people know the vg instructions differ from the RB and CA install.

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If anyone with an AEM is curious this is what my ign and inj phasing looks like now.

 

 

 

Coil /// Injector

1. 12.0///0.0

2. 4.0 ///16.0

3. 20.0 ///8.0

4. 8.0 ///20.0

5. 16.0 ///4.0

6. 0.0 ///12.0

 

Stock set up is

Coil///injector

1. 0.0///12.0

2. 16.0 /// 4.0

3. 8.0 ///20.0

4. 20.0 ///8.0

5. 4.0 ///16.0

6. 12.0 ///0.0

 

Thanks Jim wolf for making my setup confusing for all :>

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When you changed out your key/gear did you do it with the cam still on the motor or did you take it out? I have the same problem and I hate to take it all apart just to change out that gear. I have had success with eyeballing the placement but it is starting to frustrate me.

Edited by Vandergriff84

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I did it inthe car. its relatively easy to do just make sure you drill all the way thru the old one.

It is longer then the replacement, and dont follow the instructions for the z32. Ihe rb motor is 180 degrees different.

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Ok, So I have an RB25det S2 in my s30 and most everything is stock except the greddy style intake. The issue that I am having is that the ECU is retarding the timing by 15-20 degrees at idle and I have not been able to find a fix for it. If I set the CAS in the middle the car will run but will not make any power because the timing is to far below 0. If I set it all the way retarded it wont run at all. If I advance the timing all the way the motor runs good but the timing is still only at 1 or 2 degrees above 0 at idle. When I rev the motor the timing advances to 10 or 15 degrees but as soon as it drops back to idle it is below 0. I have checked that my timing bet is on correct two or three times now and everything lines up so there should not be an issue there. I have read a few threads on other sites where guys had the same exact problem but none of them have posted a solution. I know that knock is the main reason for the ECU to retard timing but it is not going into limp mode and the check engine light is not on. I also have to cam angle sensors and it does the same with both and I also have three mafs.

 

So my question is, has anyone on here had this problem and how did you fix it? What could make the ECU want to retard the timing that bad without going into limp mode?

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So I tried to reset the ECU to see if that would help and that struck out. I noticed something interesting though, when I held the throttle plate closed by hand the BTDC numbers on the consult stopped jumping around and held at a constant 15 degrees which is where it should have been since I had the CAS about half way. Does anyone know if the consult is supposed to read exactly what the CAS is seeing or is it sowing some the ECU is computing? I am still hoping that some one has seen this before and will help a guy out with a magic fix. lol.

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First verify timing. Use a spark plug wire and an actual advancing timing gun on the balancer.

Then check your TPS(sensor not switch) setting. Take it through full motion and verify with the FSM settings. The TPS as I found out recently has a massive affect on fuel and timing on the rb25.

 

Be sure to un-plug the TPS during CAS adjustment as well or it resets unless your using a real consult that will put the ECU in BASE mode.

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Ok so sorry for leaving the other half of the problem out. Before I had the consult I was trying to set the timing but I couldn't get it to idle below 800. I now have it idling low enough but when I check the timing with the light off of the wire as rayaap2 had mentioned it shows that it is extremely retarded to around -10 to -15 degrees. I have checked the cams belt and crank so I know that the motor is all lined up with the timing marks so that tells me that ECU is retarding the timing. I read another thread recently that said limp mode from knock only retards the timing by 4 or 5 degrees and I have no fault codes.

 

As far as the TPS I have it set to .47V like it should be it even shows up on the consult. If there is something else that I am supposed to do or check please let me know. I have unplugged the TPS several times when checking the timing with the light and it changes nothing.

 

So the question is what is the ECU seeing that I am not?

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Ok so this video shows you what the consult/ECU is reading. This is after I had started the motor with the tps disconnected and the CAS fully advanced. When I checked the timing with the light it was showing 0BTDC Just minutes before I shot the video I had the CAS half way and it read 15BTDC while the light was showing -5BTDC. I am at a loss with this thing so if anyone has any idea what is going on with this please let me know.

IMG_0007.MOV

Edited by Vandergriff84

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Thanks Stony for posting this.  I just finished building up my RB with an AEM EMS V2, and after trying to start, it would crank for 4-5 times and catch and start for like 1 second and then die.  Then it would be difficult to fire back up, only to catch for a sec and die again.  I have a feeling after reading this that it's 180 degrees out.  Does this sound like the same symptoms you had?  I'm going to try your switched settings and see if I can get it to fire up.

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