340 Cam Size

My father-in-law has a '68 340 with about 5k on it, that he'll sell me (only me) for $2K. I'm thinking about putting it in my '67 Dart, but not sure if it's really what I want. It is currently set-up with an M-1 intake, 2.02 X-heads (w/hardened valve seats), Milodon pan, and a 508 cam. Engine has about 5k mi on it. Sounds like a fun little motor, except my car is never going to see the track. If I bought it, I'd convert it to a stock pan, LD340 with my FiTech (currently on my 318) on top, and TTI headers, mated to my 904.

It would be fun to have the lumpy idle of the 508 cam, but I'm just wondering if it would be too aggressive for street only use (also, I need enough vac for brake booster). Honestly, I'm pretty happy with my 318 (w/stock 340 cam), and having a stock converter is nice for driving in traffic. The idea for this swap only came up because next month we're adding a/c and p/s, and converting to floor shift, so it makes sense that now would be the time to swap engines - if ever. Also, I decided to go with TTI headers, and TTI says that I need their special 273/318 headers because the 340/360 headers will leak on the 318 - so if I ever wanted to swap to a 340 later, I'd need to buy headers again $$. The engine is sitting on the stand, so it makes sense that now would be the time to swap cams. Would love to hear any/all thoughts and suggestions.

Gabe