Timing Issues - Pinging

[darkhalf]

timing depending on the type of ECU can advance from 15 degs base to about 35-50 on high load. since your ecu has been chipped... depending on who chipped it may be more

removing the CAS and getting one tooth out can make a lot of difference. if you take the CAS off and then rotate the teeth, when you put it back on the adjustment can be so far out that standard adjustment point will not get it back down to 15 degrees base @ 800rpm on a warm engine. you'll have to remove the CAS rotate a tooth backwards, put it back on and then measure the timing again and see if you can adjust it then to get 15 degrees

[MM2death]

Rotate backwards? Which way is that?

Sorry i'm a little lost here.

Scott

[MM2death]

So is this what i rotate? And rotate it the same way as the CAS itself to retard (clockwise)?

Regards,

Scott

[wrxhoon]

scott , if you didnt have the engine on tdc on the compression stroke when you fitted the new timing belt , how did you do it then ? did you just put it anywhere ? you must have been lucky if you did that cause you could have bent some valves if it was out alot .

what you have to do then is put engine on TDC on the compression stroke .

this is how you do it : take out timing belt covers , crank pulley must be lining up with mark ( 12 o'clock ) both cam pullies must be lining up with their marks on the backing plates now install the timing belt , make sure all marks ( white lines usualy depending on what brand of belt you are using )on the belt line up with the marks on the pullies when thats done you have to make sure again that pullies line up with their marks . now you have to adjust the tensioner , this is how you do it : turn the crank clockwise twice with the bolt loose now put an allen key in the hole and while holding it tighten the tensioner bolt 43-58 nm do not overtighten or it may break and dont leave loose either . just check with your hand to make sure the belt is tight .

if i remember right the cas has a slot so you cant put it in wrong but you can turn it left and right when its installed so your timing will be right .

try all that and if you have probs let me know .

[MM2death]

scott , if you didnt have the engine on tdc on the compression stroke when you fitted the new timing belt , how did you do it then ? did you just put it anywhere ? you must have been lucky if you did that cause you could have bent some valves if it was out  alot .

what you have to do then is put engine on TDC on the compression stroke .

this is how you do it : take out timing belt covers , crank pulley must be lining up with mark ( 12 o'clock ) both cam pullies must be lining up with their marks on the backing plates now install the timing belt , make sure all marks  ( white lines usualy depending on what brand of belt you are using )on the belt line up with the marks on the pullies when thats done you have to make sure again that pullies line up with their marks . now you have to adjust the tensioner , this is how you do it : turn the crank clockwise twice with the bolt loose now put an allen key in the hole and while holding it tighten the tensioner bolt 43-58 nm do not overtighten or it may break and dont leave loose either . just check with your hand to make sure the belt is tight .

if i remember right the cas has a slot so you cant put it in wrong but you can turn it left and right when its installed so your timing will be right .

try all that and if you have probs let me know .

Thanks wrxhoon.

I did all of that last night. If only i knew the correct procedure the first time around. I aligned the crack pulley's yellow mark with the mark on the lower timing belt cover, and then aligned the dimples on the cam gears with the marks on the backing plate. Then put the belt on using the marks on it as a guide to line up to.

I didn't set it up on TDC last time. I just left everything in the same position from when i last drove it and put the belt on in the exact same place...well that's what i tried to do. My dad helped me do the job but seeing he is a V8 man, all this overhead cam 'stuff' is new to him...lol

Regards,

Scott

[wrxhoon]

is it all done now ? you are very lucky you didnt bent any valves ! is it all back together now ? if you havent got the covers back on turn the engine clockwise a few times and check again all your marks when it comes to tdc and finaky check the tension on the timing belt when all done put together and check timing with timing light .

next time you take the cas out matk its position with paint or something and put together in the same spot so it starts easy and then check with timing light .

Thanks wrxhoon.

I did all of that last night.  If only i knew the correct procedure the first time around.  I aligned the crack pulley's yellow mark with the mark on the lower timing belt cover, and then aligned the dimples on the cam gears with the marks on the backing plate.  Then put the belt on using the marks on it as a guide to line up to.

I didn't set it up on TDC last time.  I just left everything in the same position from when i last drove it and put the belt on in the exact same place...well that's what i tried to do.  My dad helped me do the job but seeing he is a V8 man, all this overhead cam 'stuff' is new to him...lol

Regards,

Scott

[MM2death]

wrxhoon,

I have all the covers back on. Should i take the top one off again and turn the engine over to check?

All i have to do now is put all the belts back on and put the radiator back in. Then i will check the timing with the light.

Thanks for the help.

Scott

[MM2death]

And how do i know when i've got number 1 cylinder at TDC?

Scott

[wrxhoon]

tdc no 1 is when the crank pulley mark lines up ( 12 o'clock ) and at the same time the 2 cam pullies line up with their marks . if they all line up and the belt tension is right then its all good . did you do the tensioner bolt with a torque rench ? if you dont do it tight enough it will come loose to tight and it will break .

[MM2death]

Yep all good now wrxhoon.

Timing is now at 17deg, which is a little more retarded than with the old belt on (I marked the CAS before i took it apart).

Thanks for all the help i really appreciate it. I learnt alot about my car in the process.

I will take it for a drive tomorrow and see how she goes.

Regards,

Scott

[wrxhoon]

if you want to set it on 15 all you have to do is turn the cas a little like 1/2 a mm it will move it a couple of degrees .make sure you tighten the 2 bolts so it doesn't move . personaly i would leave it at 17 if it doesn't ping , its got to be 15 @ 650 rpm ( thats the specs )

[MM2death]

It says under the bonnet 15deg BTDC @850rpm. I thought it was 650 as well...hrmm

Yeah when i put the CAS back on i set it to roughly the middle and when i started the car and let it warm up it came down to 20deg, so i had to adjust the CAS a little. I'll see how she drives today.

Cheers,

Scott

[wrxhoon]

scott ,

both the rb25 de and det factory specs : 15 deg +or -1 @ 650 rpm , rb26 =20 +or -1 @ 950 rpm . you must have a bonnet sticker of a different car .

[MM2death]

Well it says R32 GTS-T RB20DET...oh well it doesn't matter.

BTW the car is running great now. I might get it on the dyno just to be sure everything is ok though.

Regards,

Scott

[wrxhoon]

yea but you said you have an rb25 det ??? didnt you ? rb 20 det if a different engine ( 15 deg @ 850 is correct for it ) . do you have a 25 or 20 ?

[MM2death]

RB20 man...it's in my sig.

Scott