thanks everyone on the advice...first i have a 1.5 rocker ratio as i had rocker specialities blueprint and true my rockers up, yes in need vacuum for power brakes and ac and dont want to use a pump,so i believe i will move my lobe seperation to 112, and my compression ratio should be in 9.2 to 9.4 range with the steel shim head gasket....next question becomes to go with a 224/230 or a 230/236 at 50 cam. remember my heads have been CNC ported,2.14/1.81 valves,etc.....thx everyone keith

A Cuda with 3.23 gears I'd go with the Crower 271 hdp because I know it works well.

It's basically one step hotter than a 440 magnum cam and it'll give you more torque and roll on power without killing drivability. If you were running shorty headers or a little more compression and a better intake I'd go up to the Comp 232/237 or the old Ultradyne 231/239 but honestly that Crower is a great cam.

i've been messing with a similar combo in one of my cars for several years trying to find a sweet spot; still searching. my engine is a stock 440 and basically your putting together a physically smaller 426-440 wedge. my car has a midland ross power brake booster and it just doesn't like anything 15" of idle vacuum or less. the booster does fine with 16"-17" of vacuum at idle. the cams I've tried thru the years are the stock magnum, comp cams 21-305-4, 272/.455 mopar, hughs/engle 23/30 and summit 6401. the comp cams cam will make vacuum but runs out of steam rather quickly (probably due to 106cl installed). the 272 mopar looses vacuum, summit and engle even more. going from a true 1.5 rocker to a true 1.6 rocker will loose 1" of vacuum. the faster the lobe profile with the same duration will loose some vaccum. currently i have the stock mopar cam (actually a sealed power cs661, same as stock) in the engine and vacuum is up, brakes work, drives nicely, but performance has been better. that 275hl is going to give you about .560" lift at the valve, about 15 degrees overlap at .050" (something i'd never do with stock parts).

if you insist on the 275 type cam i'd suggest an xe274 ground on something like a 113 or 114lsa. the 275 is a 274 with the added area under the curve that a 274 has with 1.6 rocker. with all the tappet/cam problems people are having i'd error towards the gentler side. the faster the lobe, the higher the rocker ratio the more spring you need. the more spring you have can kill a hydraulic tappet and cause lobe failure.

looking at the 440source website it shows some compression ratios in the low nines which is what i have. anymore i look at overlap at .050" for these scenarios. a stock cam is -11 degrees at .050". from the cams i've used I've found anything at zero degrees and above will noticeably effect low rpm vacuum. the summit 6401 has about +1 degree overlap at .050" but can reduce idle vacuum by 2". the mopar 272 has zero degrees at .050" and will reduce vacuum. my favorite performer was the engle 2330 but at 110lsa it will noticeably reduce vacuum at idle. adding a higher ratio rocker to a stock cam will add some area under the curve plus some lift but will reduce vacuum a little. enhancing the timing curve only marginally helped vacuum. there're no free lunches here or magical cams. it all needs to be thought out. of course, a vacuum reservoir canister can be added; i just couldn't find a decent place for the black lump in my engine bay.