The 510 Realm

Scratching my head here and may need some input from old timers. When I was running Shadbolt M445 cams back in the late 70's to early 80's, I swear the valve lift was under .500". ( .480" to be exact ). Now I'm finding info from here that M445 grinds from 2003 ( Merlin's Post ) have the Cam Tag stating that lift is .507" at the valve.

Does any one know if their were revisions made to the grind over the decades it was produced?

With FT pistons on L-serie's, are valve reliefs necessary with the M445 cam? . It's been so long that I can't remember if I had valve reliefs on my L24 with Flat Tops. I'm thinking I didn't. Question is for member on another Forum who is building an L-28 with Flat Tops and an M445 Cam.

Ironically, My car has an L-28 with FT pistons, no valve reliefs and a " Mystery " cam of 280 degrees. I say mystery Cam becuase engine builder wouldn'tb tell me what specs he used... but had a surprised look on his face when I asked if he used an M445 grind . Engine feels like it has an M445 cam. Nice lope at idle. Good mid-range and pulls hard to 7,000.

Why not phone Shadbolt and talk with them? Last time I spoke to them found that they were very knowledgable. They will also be able to confirm weather or not you can run FT pistons.

I'm just trying to help another member out on a different forum. He has just bought a used head that includes an M445. Since I'm not going to be purchasing any product, I don't really feel comfortable wasting the Vendors valuable time. Thought there were enough old farts lurking about here that someone might have a better memory than me....

May have to give Shadbolt a call. Who's running the place now?

I understand. Yes you would think that someone else would chime in here with the same cam or at least more experience in the L series to answer your question. Guy I spoke to was more than willing to provide information, did not catch his name though...

This old fart/ racer/mechanic ,I can say that you can run a M445 Shadbolt cam with flat top pistons with no valve relief needed. I ran a L16 with 240z flat top pistons. M445 is about .506 valve lift and 280 degree adv. duration. Also I have built a few Z engine for customers over the years with this combo.
The nice thing about the M445 , you can run stock valve spring with stock retainers and .180 lash pads. [aprox on lash pads]. for a nice street combo.
All ways double check during engine mock up. Keep in mind , if head has been milled down,head gasket compressed thickness should be taking into account. Hope this helps you.
Ian M. old racer fart

Barry at Shadbolt stills answers the phone. Very nice man to deal with.

Yes, it certainly does. Thankyou.