Cam Timing Help Needed -- Marks Built / Goodson Performance M20 Head

[ynwaE]

Hey guys, hoping someone can help me out. I recently had some work done on my 1990 325i and my mechanic discovered my cam timing was advanced a tooth - he corrected it back to stock for fear of blowing a valve. The car now feels slower but still runs great.

Dug up the original invoice on the head/cam work from the previous owner and here's what I'm working with:

- Marks Built M20 head
- Ported and polished with intake matching
- Swirl chambers on intake side only
- Angle milled 15 degrees (noted as adding ~2 degrees of advance to cam timing)
- Built by Reed at Goodson Performance
- .470 lift intake / .486 lift exhaust
- New guides, seats, and TRW valves

Given the angle milling already adding ~2 degrees of advance to cam timing, I'm wondering if running the cam a tooth advanced was actually more correct for this setup than stock spec.

Does anyone have a similar setup? What does your timing look like? And does anyone know the overlap timing on this cam? Trying to figure out if I need to dial it back in advanced to get my power back. Also wondering about getting an adjustable cam gear.

Appreciate any help.

[digger]

it wouldn't have been angled milled 15 degrees it isn't physically possible nor would this head lend itself to angle milling. it is pretty much not going to run better off by a whole tooth unless the cam was poorly made

to understand how it is setup you need to degree it to the cam card or make some informed judgments when degreeing by deducing the cam specs using a degree wheel and dial indicator if you dont have the cam card. you'll need an adjustable cam gear to make any adjustment finer than 1 tooth