Timing Issues

[steeldawg_69]

What's up guys, I have been having some really serious issues with my build. I recently redid my engine and my ignition timing is way off. I have done the mechanical timing over 6 times now and each time I have done it I have rotated the engine several times to make sure the crank and cam marks line up, they always do, dead on. When the ignition timing is done the most I can get out of it is 15 degrees BTDC. When I remove the front cover with the RB logo on it, I'm able to adjust the timing to 20 degrees BTDC, but then CAS is not centered and I have very little adjustment left. I have Tomei procams, 260 duration, 10.80mm lift with adjustable cam gears. Yes, I have tried searching but I have not been able to find anyone with a similar problem to mine. The only information I have been able to get is I read somewhere that if my CAS is turned all the way advance then I'm doing something wrong, the thing is I don't know what I could be possibly doing wrong. The motor is swapped into a Nissan 240sx, and that is the one major issue I've been having with the car. I appreciate any suggestions, thanks.

[Ben C34]

You need to unplug the tps so the ecu locks the timing to 15 degrees. Otherwise the ecu will vary timing as a strategy to maintain target idle rpm.

[steeldawg_69]

Ok, I tried that, still having the same issue with the timing, thanks for the input though, appreciated.

[Kinks]

stock ECU?

[STATUS]

also use a plug wire between coil and plug, if you use the back timing loop and dont know the trick it will give an incorrect reading.

[steeldawg_69]

Nope, not stock ecu but I can get my hands on one, I used both methods to check the timing and they both give the same results. I noticed something else this morning, the exhaust cam bolts are rubbing on the inside of the cas. I think the rubber cas seal that I have is the wrong one, it has no metal where the cas bolt would go, I was trying to post a link that has a similar one to mine but this thing is not allowing me to paste, I'll take pictures tomorrow.

[Kinks]

The "unplug TPS to lock 15 degrees timing" trick only works on stock ECUs. If you're running an aftermarket ECU it should have a way to lock the timing through the tuning software.

So if you're not running stock ECU then unplugging the TPS did nothing and your timing will be walking all over the place trying to maintain the desired idle speed.

[r32-25t]

I think he has bigger issues in the fact the bolts are rubbing the inside of the crank angle sensor

[blind_elk]

I thought 15BTDC was the "factory" timing figure? So, what's the problem? If you have adjustable cam gears, then any deviation from 0 offset is going to change where the CAS sits at the correct timing. So, what's the problem?

[steeldawg_69]

I was told that the correct timing is 20 Deg BTDC, correct me if I'm wrong please. Everywhere I looked while researching said the same thing. I have played around with the adjustable gears and that has not had any effect on the cas position which seems a little odd to me. Also the cams have been degreed. I found out that I bought the wrong cas gasket (seal, whatever they call it), hence the reason for the bolts rubbing.The car will start, idle and shuts off after about 7 to 10 mins of idling. Once it shuts off it wont start again. Also if I blip the gas pedal while it is idling it goes past the idle speed and shuts off and once that happens it will not start. I have checked and cleaned the iaac valve, changed it and still having this problem. I checked the coolant temp sensor and it is ok. There are times when the car will start idle and the af ratio will be 13.5 and then it leans out to 17, another time it gets pig rich. All this seems to me to be potentially a wiring issue so I'll be pulling the harness this weekend and I'll keep you guys updated.

[GTSBoy]

Manual 15. Auto 20.

[steeldawg_69]

This is the seal I bought, notice it does not have the metal rings around the bolt holes.

[steeldawg_69]

OK, thanks for that correction.

[r32-25t]

Rb26 is 20°btdc, rb20/25/30 are 15°btdc

what ecu are you using? Does it retain the air flow meter? cause it kinda sounds like it is on its way out

You didn't buy the wrong one, you need to take the metal rings out of the old gasket and put them in the new one

[steeldawg_69]

I have a stock ecu and another one that came with the motorset slightly modded. So the timing is 20 BTDC?

[steeldawg_69]

I was wondering if I have some stray voltage feeding into the ecu, so I'm going to check the harness.

[steeldawg_69]

Lol, oh boy that old one is long gone my friend. I ordered one from RHD Japan so I hope it will have them in.

[r32-25t]

What engine is it?

[steeldawg_69]

Rb26 in a 240sx

[r32-25t]

Ok then yes it's 20°

I would say they over fueling and dying issue is you have a dicky airflow meter or an intercooler pipe that isn't sealing properly

You will need to get on to rhd and order the three metal spacers before continuing tho