340 mopar cam question?

[joshua dewitt]

have a p4452782 .430/.44 268/276 mopar performance cam and lifter pkg. new in the box. looking to use it itn my built 318.... my question though is it states 114 center line.... i have been seeing and hearing of a miss print known on this center line and ground differantly than stated... any truth to this? one engine built i can degree it to know for sure but might be a while... just looking into it more....

 

[Abodybomber]

Did some detective work. Summit Racing's site,listed these specs:
Summit Racing Part Number: DCC-4452782
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: Idle-5,800
Intake Duration at 050 inch Lift: 228
Exhaust Duration at 050 inch Lift: 235
Duration at 050 inch Lift: 228 int./235 exh.
Advertised Intake Duration: 268
Advertised Exhaust Duration: 276
Advertised Duration: 268 int./276 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.429 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.444 in.
Valve Lift with Factory Rocker Arm Ratio: 0.429 int./0.444 exh.
Lobe Separation (degrees): 114.
So the lobe separation is 114.Center line usually refers to the intake opening centerline. Usually aftermarket cams,are 4 degrees advanced .This would put it ,on a 110 intake centerline. Not positive ,on Purple Shafts. Hopefully,some one else chimes in.That way,we both learn perhaps.

 

[340 8BBL]

i would not trust any of the listed specs.ive had a 280/474 purple cam profiled in front of me and its a fair amount different than whats listed.id also be willing to bet that the duration @50 numbers are more like 210*/220* for the cam you have,rather than 228*/235*.the intake centerline is probably 112.

 

[rumblefish360]

That cam with the 114 listing is the OE 340 cam and is correct.
The upgraded replacement 340 cam is on a 110. It is a bigger and more agressive cam. It is not radical and totally streetable.

 

[RustyRatRod]

Are you talking about the MP .430/.450 lift cam? That's a good cam, but not an upgrade from the stock 340 piece, IMO.

 

[rumblefish360]

Bobby, is the question directed at me?
My answer would be look at the duration specs @ .050.