340 528. Purple cam question

That cam is IMO,a lot more cam than you need for 375/400. Unless you're running some lo-po heads, or a teener . IIRC that cam is about [email protected]
To make the 375/400 in a streeter, You'd be way ahead to put the power in the heads, run a 360, and a small hydro of about [email protected], perhaps even a hair less.
I mean how often are you gonna get to rev that thing to 7000 with 3.55s, since that is about 60 mph in first gear with a stick. And also with a stick, to take off briskly the 2.66x3.55=9.44 starter gear, coupled with the low-rpm torque characteristics of that cam, means a lotta clutch slipping. I mean there ain't a lot of torque below 20mph.While the Duster is light, IMO it ain't light enough for that cam and 3.55s. She'll be wanting something in the 4.xxs. With 4.30s it could be a monster.
Don't forget for your SBM to live at that high rpm, there are some oiling mods that you have to make, else you may be rebuilding the engine a lot earlier than you had planned. Whereas the 228 cam, will peak a good 400 rpm lower, and with a stick might want to be shifted at around 6000/6200. Although with the right combo, you may enjoy stretching it out a little higher from time to time.
Once again, put the power in the heads. It might be a lil pricey to start with, but you will save tons of money in the long term

Just my 2cents,again