HI I am in need of some help if i may, I am currently updating the cam on my 351c 4vcc heads .030 , the cam i have chosen is a 275/225@50 515 lift 113 lsa I was wandering what the best icl for the 4v heads would be? i am thinking 108?
Original Post
Best? Define best?
108° is really a camshaft centerline for a race engine running open exhausts and/or a stock cylinder head with major radical exhaust port modifications like the '73 era "Pro-stock" exhaust modification.
Why your cam only had 10 inches running makes no sense. That is a very mild cam profile provided the total overlap was under 63° or so, but I don't think that you stated that in the specs?
My Compcam has 63° of overlap and gives me 14.
https://www.compcams.com/magnu...-351c-351m-400m.html
I'd recommend that you use "George's" cam spec's if you are going to have a cam ground and you want a good idle.
The exhaust ports on stock Ford iron 351-c heads are just plain bad and for those a 113° makes complete sense.
I've had good response using Compcams solid lifter cams. They use 110°. For the street you want to limit the duration at .050". A 236° @.050 will do you fine. Their next step up is a 244° @.050" and will give you the same results as what you are replacing.