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hey all, i want to check my CAS timing, and have no idea how to, nor do i have the tools, does anyone in the SE have the tools and know what to do? and know your shit regarding them? as they can be fatal if not done correctly!

cheers

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goto autobarn and buy a timing light

thats all you need

once engine is warm and running use the timing light (it will come with instructions) to read base timing

for rb25 it should be bang on 15deg. if you get any other number, your CAS is offset and must be adjusted

when i say offset, as in, it is dialed forward or backward. at idle, the timing is locked so for rb25 it is always 15deg

so if your timing light said say 12deg, then this means your entire tune is 3deg off, which means it will be sluggish

the ECU assumes your timing is bang on as per the CAS and won't know if its offset (ie backdialed/forward)

once you adjust, run a check with timing light and keep going until you get to 15deg at idle

goto autobarn and buy a timing light

thats all you need

once engine is warm and running use the timing light (it will come with instructions) to read base timing

for rb25 it should be bang on 15deg. if you get any other number, your CAS is offset and must be adjusted

when i say offset, as in, it is dialed forward or backward. at idle, the timing is locked so for rb25 it is always 15deg

so if your timing light said say 12deg, then this means your entire tune is 3deg off, which means it will be sluggish

the ECU assumes your timing is bang on as per the CAS and won't know if its offset (ie backdialed/forward)

once you adjust, run a check with timing light and keep going until you get to 15deg at idle

ok, i guess ill give it a try.

if say its off by 3 degrees, how do i know which way to turn the cas to correct it? im assuming just so the bolts are center of the holes?

no idea, someone on here would know how to use a timing light on RB25

surely it can't be hard ? the timing light will tell you what timing you have at idle

it should be 15deg for rb25. so if at idle the timing light tells you any other number than 15, your cas needs to be adjusted

no idea, someone on here would know how to use a timing light on RB25

surely it can't be hard ? the timing light will tell you what timing you have at idle

it should be 15deg for rb25. so if at idle the timing light tells you any other number than 15, your cas needs to be adjusted

ok, cheers mate, hopefuly someone has a read of this thread and posts how to hook the lines into the spark plugs

The timing light comes with a spark plug socket and also a clip which can be clipped to a specific wire. On the rb25 at the back of the block where the coil pack wire harness is you should see a white wire I think sticking out you clip the light to that.

depends on what timing light you get, the crap one usually can only pick up the signal from HT lead which you don't have in RB25 so what I normally do if I have to use bottom of the range timing light, I undo the No.1 coil pack with 8mm socket which is the first one you see when you open the bonnet. then connect the spark lead between the coil pack and spark plug then. Fron there you can clip the timing light signal pick up to the lead and connect 12v

ok will do

so does the timing light say as a figure what degree its out?

and how do you connect them to the plug if it has coilpacks? they are completely enclosed :S

Hook it up as Panko described (you can get a short spark lead when you get the timing light).

You read the timing on the crank pulley (big one down the bottom of the front of the engine). There is a set of 7 marks at 5 deg increments, which move from driver side to passenger side (L->R as you stand looking into the engine bay). The last mark (left-most) is TDC (Top Dead Centre). Each time the coil fires on the #1 cylinder, the timing light will flash its light. The flash will "stop" the crank pulley so you can read which mark is aligned with the pointer located on the crank case cover. You want 15 deg BTDC (Before TDC), which should be the 4th mark (from either end).

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