Cam timing adjustment

[karlblues2]

OK. Stupid question time. Can anyone tell me what would happen by advancing the cam timing by one tooth on the ABY engine. What is a single tooth worth - is it 5degrees / 15degrees or what? Plus what impact would that have throughout the rev range, low revs through to redline?
Finally, would a remap be required to compensate for that?
I am attempting to reduce the lag in the lower end of the rev range Currently everything is spot on factory markings. I am asking Mihnea for a remap anyway to address this low rev range lag (if it's possible), but I was curious as to what impact physically advancing the top cam timing would have.
Thanks in advance
Stupid question over.
Cheers
Karl
Oz

[Jeffer]

If I think out loud. And I'm no expert in this.
1 rotation of the camshaft (360 deg.) diveded by 52 tooth on the sprocket = 6,9 degrees. Times 2 (because the cam turns 720 degree on one crank rotation) gives 13,8 degree when you jump one tooth either side.

360/52=6,9x2=13,8 degree...?

I think this should be it........But correct me if I'm wrong

Cheers

[karlblues2]

If I think out loud. And I'm no expert in this.
1 rotation of the camshaft (360 deg.) diveded by 52 tooth on the sprocket = 6,9 degrees. Times 2 (because the cam turns 720 degree on one crank rotation) gives 13,8 degree when you jump one tooth either side.

360/52=6,9x2=13,8 degree...?

I think this should be it........But correct me if I'm wrong

Cheers

Thanks Jeffer
So what effect will that have on the way the car runs? Will it pull better down low at the expense of higher revs?

[Jas11n]

Erm, I'm not clued up in any way with stuff like this, but,
my timing was found to be out 2 teeth advance whilst having timing belt changed on rebuild after I stuffed it.
I used to have way more lag then my brothers indentical stock 95 ABY.

[karlblues2]

Erm, I'm not clued up in any way with stuff like this, but,
my timing was found to be out 2 teeth advance whilst having timing belt changed on rebuild after I stuffed it.
I used to have way more lag then my brothers indentical stock 95 ABY.

Thanks mate
So that says advance = lag ?? Therefore does back one tooth = less lag?
Cheers
Karl
Oz

[Uukrul]

So that says advance = lag ?? Therefore does back one tooth = less lag?

rather that says factory timing = less lag.

[BeckyA4]

Leave the cams at factory settings!! 13.8 degs is a lot to move a camshaft. If you want to adjust the cam timing then get special pulleys made, then it can be done accurately. What cams have you got??

[BeckyA4]

****** im logged on as Becky

Cheers

Tom

[4WheelDrifter]

Sure that's not Becky?

[karlblues2]

Leave the cams at factory settings!! 13.8 degs is a lot to move a camshaft. If you want to adjust the cam timing then get special pulleys made, then it can be done accurately. What cams have you got??

Thanks Err Tom, I mean Becky, I mean Tom
I have stock ABY cams, and they are set to factory settings, but I am tring to reduce lag by advancing the timing. I want to do it through a remap with Mihnea, but I was asking what impact moving the sprocket would have. Cheers
Karl
Oz

[Doug_RS2]

Did you check the cam pulley woodruff key? That was still ok? The timing can still be out with all the marks in the right place if that is broken. It is very common for that to break if the cams are not locked in place when tightening the cam pulley.

[karlblues2]

Did you check the cam pulley woodruff key? That was still ok? The timing can still be out with all the marks in the right place if that is broken. It is very common for that to break if the cams are not locked in place when tightening the cam pulley.

Hi Doug. Thanks mate. Can u tell me where I can find the cam pulley woodruff key and how I get to it to check?
Cheers
Karl
Oz

[Doug_RS2]

It is on the cam pulley - the small bit of metal that locates the cam pulley onto the cam. If this has broken then the cam can turn when being tightened and although the marks all line up on the cam, crank, and flywheel - and the 2 cams line up together - it will be out timing wise. I think you have to remove the cam pulley. I will check later if it is visible without removing.

I'll take a couple of pics if I can get access.

HTH

[4WheelDrifter]

Hi Karl. HTH.

[Doug_RS2]

that is it - no point in me taking a picture as you cannot see without removing the cam bolt.