Cam degreeing
Posted: Sat Feb 19, 11 6:33 pm
Anyone degreed a cam with the engine in the car? What size degree wheel will clear the crossmember?
I fitted a new cam a few months ago without degreeing it. It's the Mopar 528 solid and I had assumed the cam was ground straight up, so I installed it 2* advanced using a 9 way timing set. I did a bit of searching and couldn't find anything that said advance was ground in or not. Decided to check it today using the valve lash method, check the bottom of this page.
http://www.iskycams.com/degreeing.php
I was surprised how conclusive this was. Verified TDC on the damper first using a piston stop and had to adjust the pointer on the timing cover about one degree. Luckily it's a bolt on pointer so I could move it a bit.
Checked the cam at TDC and the intake lash was a lot more than the exhaust lash so it was advanced. Did it all again, this time using 4* BTDC and still advanced. Again at 6* BTDC and this time retarded. Finally one more time at 5* BTDC and the cam was straight up, same lash on the intake and exhaust give or take a few thou.
The LSA is 112* so the cam is installed at 107*.
Looks like they do grind a few degrees into the cam. Runs fine on the street so I'll leave it there for now but may retard it later. It just looks like a pig of a job with the engine in the car.
I fitted a new cam a few months ago without degreeing it. It's the Mopar 528 solid and I had assumed the cam was ground straight up, so I installed it 2* advanced using a 9 way timing set. I did a bit of searching and couldn't find anything that said advance was ground in or not. Decided to check it today using the valve lash method, check the bottom of this page.
http://www.iskycams.com/degreeing.php
I was surprised how conclusive this was. Verified TDC on the damper first using a piston stop and had to adjust the pointer on the timing cover about one degree. Luckily it's a bolt on pointer so I could move it a bit.
Checked the cam at TDC and the intake lash was a lot more than the exhaust lash so it was advanced. Did it all again, this time using 4* BTDC and still advanced. Again at 6* BTDC and this time retarded. Finally one more time at 5* BTDC and the cam was straight up, same lash on the intake and exhaust give or take a few thou.
The LSA is 112* so the cam is installed at 107*.
Looks like they do grind a few degrees into the cam. Runs fine on the street so I'll leave it there for now but may retard it later. It just looks like a pig of a job with the engine in the car.