Cam question

[455cutt82]

I am looking at tossing in a Howard's cam in a 455 does this require any other modifications to the valve train? Besides new lifters.

 

[Evan11]

I am looking at tossing in a Howard's cam in a 455 does this require any other modifications to the valve train? Besides new lifters.

Valve springs wouldn't hurt. And depending on how much lift, you could need roller rockers if you're after a very radical cam.

 

[455cutt82]

here are the cam specs
Cam Style Hydraulic flat tappet
Basic Operating RPM Range 2,600-6,400
Intake Duration at 050 inch Lift 235
Exhaust Duration at 050 inch Lift 245
Duration at 050 inch Lift 235 int./245 exh.
Advertised Intake Duration 289
Advertised Exhaust Duration 299
Advertised Duration 289 int./299 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.520 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.544 in.
Valve Lift with Factory Rocker Arm Ratio 0.520 int./0.544 exh.
Lobe Separation (degrees) 110
Computer-Controlled Compatible No
Lifters Included Yes
Lifter Style Hydraulic flat tappet

 

[khan0165]

that seems pretty radical over a stock cam. Your duration is thru the roof...
I'm curious how your heads will respond to a 110 LSA

a buddy of mine is using a milder cam on his 455, and he had to replace springs to handle over 0.500 lift

 

[Evan11]

here are the cam specs
Cam Style Hydraulic flat tappet
Basic Operating RPM Range 2,600-6,400
Intake Duration at 050 inch Lift 235
Exhaust Duration at 050 inch Lift 245
Duration at 050 inch Lift 235 int./245 exh.
Advertised Intake Duration 289
Advertised Exhaust Duration 299
Advertised Duration 289 int./299 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.520 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.544 in.
Valve Lift with Factory Rocker Arm Ratio 0.520 int./0.544 exh.
Lobe Separation (degrees) 110
Computer-Controlled Compatible No
Lifters Included Yes
Lifter Style Hydraulic flat tappet

You need roller rockers. That cams pretty wild

 

[455cutt82]

I have not dropped the hamme on the cam yet any others I should check out

 

[Evan11]

I have not dropped the hamme on the cam yet any others I should check out

Is this a olds 455? A comp 268 or 270 would be more practical IMO.

 

[455cutt82]

yes it is a Oldsmobile 455.

 

[Evan11]

yes it is a Oldsmobile 455.

ok, you should check into those cams

 

[455cutt82]

Will these require any modifications to the valve train?