What is the most radical cam you can run in a 390 Caddy while still using the stock rockers,pushrods,and lifters? I want something with a lumpy idle. preferably one I can buy without having to get a custom grind How would this work? valve lift: .480/.480 adv duration: .268/.268 duration @50: .218..218 centerline: 108/112
PM 32coupedeville on here. He has a nasty cam in his 390 Caddy. Not sure if it was a custome grind or not.
If you want a rough idle, look for an LSA narrower than 112. 108 or 110 and you will want more than 218 @ 050. In the cam you listed, 108 is the installed intake centerline, 112 is the LSA. In a light car like your roadster, I would be looking for something around 230@050 on a 108 LSA, but something like that for an early cad will probably be a custom grind.
What about this one? Valve Lift (INT/EXH): .450/.450 ADV Duration (INT/EXH): 280/290 Duration @ .050" (INT/EXH): 203/203 Centerline (degrees): 111 Power Range (RPM): 1200-4700
Thats even smaller than the first one. A one degree difference in LSA is not going to make up for 15 degrees less duration.
Look for something around 225-230 @ .050 on a 108-110 LSA. Narrower LSA will idle rougher and have more mid-range grunt if you are comparing two otherwise identical cams.
It's my understanding you want to get in touch with Nielson Cams([email protected])...I am building a 1962 Cad 390, for my 36 Ford coupe and have run into the same questions. I guess that is the price we pay for not using a small block Chev! I think the price on a custom grind for a Cad is about $200-250, but do not know for sure as i have not ordered mine as of yet. Please keep me posted.
Finally got a cam,this is the one I got----same cam that was in the HR Deluxe Caddy build,except for lobe center
One reason is the base circle diameter is smaller than most cams. This makes for a higher rate of lift which makes for faster wear. The material the core is made of also affects wear and obviously they are not going to spend any more than is necessary for that. The good news is, steel cams, both flat tappet and roller stand up very well. The after market cast cams also do very well. The factory came out with an unpublished note to dealers in 1950 that they expected in excess of 1% of the cams to fail in the first 200 miles. "Been in the cam business 59 years"
Pete they had a lot of trouble with cam and lifter wear on the new OHV V8s at that time. Chrysler and Studebaker as well as Cadillac. All these companies had good engineers and lots of experience building engines but they were breaking new ground with the OHV models. The solution turned out to be better lifters, I believe some changed to chilled iron, and adding ZDDP to the oil. Now that they are taking the ZDDP out of oil this is something to watch out for especially on a new cam.
I have a crower roller in My 390 from back in the 60s. Unsure of the grind. But I would think you would want some heavier valves springs and adj. rockers with chaging the cam. Also with any flat tappet cam you get new lifters for a new cam so they break in together or atleast thats what I understand.
Got new lifters and heavier springs--don't need adj rockers unless using solids or regrind I have a set of Stude adj rockers if U know anyone that needs them---$150.00
I think thats how you get a lumpy idle is with solid lifter not hyd. I could be wrong. that and the right cam
I think you mean lobe separation I could be wrong. I think you only get the full effect of the cam at idle is with solid lifters. hydraulic gives you a smoother idle. Like I said I could be wrong but thats what I understand.
It's more a matter of the camshaft's specs, not what type of lifters it uses. You can buy a hydraulic cam that will barely idle, if that's what you're into......and every stock Ford flathead and Y block had solid lifter cams from the factory, and they weren't wild grinds by any measure.
I have about the biggest cam you can run in a 390 with stock rockers and pushrods, done by cam craft in MD, I think they are in SC now, it is in a 5200lb 1960 Cadillac convertible, and it has a lumpyish idle, but I can say with th factory tri-power, it will light the tires up right off idle. Call them, they sold me a new cam and lifters for cheap money, and it makes good power. The duration is the biggest change you can make, because of the non adjustable rockers, you are limited on the lift.
The Jalopy Journal
