Hi! JEB from FINLAND,
I´m building 1973 454 engine from impala. Got 049/ oval port open chamber heads with stock valves. So my question is how much dome i need in piston and how aggerssive cam i can use to get all out from those stock heads? bore is 4.280 stroke is stock 4" and rods are stock too.
I was thinking COMP Cams Magnum Hydraulic Cam and Lifter Kits K11-208-3 - Free Shipping on Orders Over $99 at Summit Racing is that any good? Looks good packet with sprins etc.?
Ps. Sorry my bad english.
Looking something 10:1 compression.. cam should be good with street/strip. Little rough idle would be nice
what is split cam? I hear that my heads cant handle too aggressive cam with out bigger valves and some porting witch i dont want to do.[/quote]
valve seat and back face angles ,valve diameter and valve lift and duration effect the flow thru the curtain area
keep in mind that valve may be forced off its seat, too full lift and re-seating 50 plus TIMES A SECOND at near 5500 rpm, so theres very little TIME for gases to move through the very restrictive space between the valve seat and valve edge
Calculating the valve curtain area
The following equation mathematically defines the available flow area for any given valve diameter and lift value:
Area = valve diameter x 0.98 x 3.14 x valve lift
Where 3.14 = pi (π)
For a typical 2.02-inch intake valve at .500-inch lift, it calculates as follows:
Area = 2.02 x 0.98 x 3.14 x 0.500 = 3.107 square inches
split cam= different intake and exhaust lobe duration's and possibly lift specs.
write a list of all factors that will influence the cam selection choice, CALL AT LEAST 6-9 DIFFERENT CAM MANUFACTURERS, 7-9 WILL BE EVEN BETTER!,
DON,T LIE tell them EXACTLY what you expect and what you have currently ,installed,
and that the cam must work with NOW, NOT what you intend to install later.
DO NOT DISCUSS IN ANY WAY WHAT ANY OTHER MANUFACTURER SUGGESTED,
OR THAT YOU'VE EVEN TALKED TO ANY OTHER MANUFACTURER
YES you NEED too KNOW your COMPRESSION RATIO, and all the other answers to the questions below BEFORE calling....knowing a few more things, than your want a lope in the engines idle and you want a fast car when your done, about your combo , like your static compression ratio, displacement, cylinder heads used, rocker ratio, max valve spring clearance, or coil bind, height, spring load rates, carb,size, if its a vacuum or manual secondary carb, intake manifold,(single or dual plane,) headers, dimensions, your car weight, tire diam., do you need to pass emission testing? are you racing the car or is it daily transportation,etc would sure help, in the cam selection process??
selecting a cam without knowing those factors, is rather like marrying a girl based only on the color of her hair brush, you might make a good match but the odds say your dreaming
car weigh?
rear gear ratio?
tire diam.
trans and gear ratios?
stall speed if its an auto?
displacement?
COMPRESSION RATIO
HEADS (flow numbers)(lift restrictions)
intake type
tire size
intended use
max rpms
launch rpms
MIMIMUM IDLE
fuel octane
carbs,mpfi? CFM
ETC.
knowing a few more things, than you want a lope/ rumble in the engines idle sound , and you want a fast car when your done, about your combo , like your static compression ratio, displacement, cylinder heads used, rocker ratio, max valve spring clearance, or coil bind, height, spring load rates, carb,size, if its a vacuum or manual secondary carb, intake manifold,(single or dual plane,) headers, dimensions, your car weight, tire diam., do you need to pass emission testing? are you racing the car or is it daily transportation,etc would sure help??
selecting a cam without knowing those factors is rather like marrying a girl based on the color of her hair brush, you might make a good match but the odds say your dreaming
AVERAGE the RESULTS FROM EACH manufacturers suggestion,as to lift, duration and LCA and buy the cam thats the closest match to that average
this is generally a good street/strip cam in a 10:1 454,
but obviously calling several cam manufacturers would be a good idea
BBC 454 to 470 CID ?Old School? OEM 049/781 heads to a max of 5700 RPM - hydraulic roller camClay Smith Cams
or
Bootlegger Hydraulic Flat Tappet Cam - Chevrolet Big Block 277/304 - Lunati Power
CRANE
http://www.cranecams.com/uploads/lobe/masterlisting.pdf
CROWER
Crower master catalog for high performance engine parts
ISKY
Page Not Found - Isky Racing Cams
claysmith
Camshafts - Clay Smith Cams
engle cams
http://www.englecams.com/downloads/2010 ... atalog.pdf
elgin cams
http://catalog.elginind.com/app/engine_ ... by+Part+No.
herbert cams
Buy Performance, Comp, Roller Cams Online
howard
http://www.howardscams.com/howards2015.pdf
lunati
Cams - Lunati Power
almost every mechanics tool box needs a few basic measuring tools and supplies
https://www.amazon.com/Claytoon-Set...d=1466872286&sr=8-17&keywords=plastilina+clay
http://www.utrechtart.com/Plastalin...currency=USD&gclid=CN3G75zOw80CFQgaaQodKbgFjA
I´m building 1973 454 engine from impala. Got 049/ oval port open chamber heads with stock valves. So my question is how much dome i need in piston and how aggerssive cam i can use to get all out from those stock heads? bore is 4.280 stroke is stock 4" and rods are stock too.
I was thinking COMP Cams Magnum Hydraulic Cam and Lifter Kits K11-208-3 - Free Shipping on Orders Over $99 at Summit Racing is that any good? Looks good packet with sprins etc.?
Ps. Sorry my bad english.
Looking something 10:1 compression.. cam should be good with street/strip. Little rough idle would be nice
valve seat and back face angles ,valve diameter and valve lift and duration effect the flow thru the curtain area
keep in mind that valve may be forced off its seat, too full lift and re-seating 50 plus TIMES A SECOND at near 5500 rpm, so theres very little TIME for gases to move through the very restrictive space between the valve seat and valve edge
Calculating the valve curtain area
The following equation mathematically defines the available flow area for any given valve diameter and lift value:
Area = valve diameter x 0.98 x 3.14 x valve lift
Where 3.14 = pi (π)
For a typical 2.02-inch intake valve at .500-inch lift, it calculates as follows:
Area = 2.02 x 0.98 x 3.14 x 0.500 = 3.107 square inches
split cam= different intake and exhaust lobe duration's and possibly lift specs.
write a list of all factors that will influence the cam selection choice, CALL AT LEAST 6-9 DIFFERENT CAM MANUFACTURERS, 7-9 WILL BE EVEN BETTER!,
DON,T LIE tell them EXACTLY what you expect and what you have currently ,installed,
and that the cam must work with NOW, NOT what you intend to install later.
DO NOT DISCUSS IN ANY WAY WHAT ANY OTHER MANUFACTURER SUGGESTED,
OR THAT YOU'VE EVEN TALKED TO ANY OTHER MANUFACTURER
YES you NEED too KNOW your COMPRESSION RATIO, and all the other answers to the questions below BEFORE calling....knowing a few more things, than your want a lope in the engines idle and you want a fast car when your done, about your combo , like your static compression ratio, displacement, cylinder heads used, rocker ratio, max valve spring clearance, or coil bind, height, spring load rates, carb,size, if its a vacuum or manual secondary carb, intake manifold,(single or dual plane,) headers, dimensions, your car weight, tire diam., do you need to pass emission testing? are you racing the car or is it daily transportation,etc would sure help, in the cam selection process??
selecting a cam without knowing those factors, is rather like marrying a girl based only on the color of her hair brush, you might make a good match but the odds say your dreaming
car weigh?
rear gear ratio?
tire diam.
trans and gear ratios?
stall speed if its an auto?
displacement?
COMPRESSION RATIO
HEADS (flow numbers)(lift restrictions)
intake type
tire size
intended use
max rpms
launch rpms
MIMIMUM IDLE
fuel octane
carbs,mpfi? CFM
ETC.
knowing a few more things, than you want a lope/ rumble in the engines idle sound , and you want a fast car when your done, about your combo , like your static compression ratio, displacement, cylinder heads used, rocker ratio, max valve spring clearance, or coil bind, height, spring load rates, carb,size, if its a vacuum or manual secondary carb, intake manifold,(single or dual plane,) headers, dimensions, your car weight, tire diam., do you need to pass emission testing? are you racing the car or is it daily transportation,etc would sure help??
selecting a cam without knowing those factors is rather like marrying a girl based on the color of her hair brush, you might make a good match but the odds say your dreaming
AVERAGE the RESULTS FROM EACH manufacturers suggestion,as to lift, duration and LCA and buy the cam thats the closest match to that average
this is generally a good street/strip cam in a 10:1 454,
but obviously calling several cam manufacturers would be a good idea
BBC 454 to 470 CID ?Old School? OEM 049/781 heads to a max of 5700 RPM - hydraulic roller camClay Smith Cams
or
Bootlegger Hydraulic Flat Tappet Cam - Chevrolet Big Block 277/304 - Lunati Power
CRANE
http://www.cranecams.com/uploads/lobe/masterlisting.pdf
CROWER
Crower master catalog for high performance engine parts
ISKY
Page Not Found - Isky Racing Cams
claysmith
Camshafts - Clay Smith Cams
engle cams
http://www.englecams.com/downloads/2010 ... atalog.pdf
elgin cams
http://catalog.elginind.com/app/engine_ ... by+Part+No.
herbert cams
Buy Performance, Comp, Roller Cams Online
howard
http://www.howardscams.com/howards2015.pdf
lunati
Cams - Lunati Power
almost every mechanics tool box needs a few basic measuring tools and supplies
http://www.utrechtart.com/Plastalin...currency=USD&gclid=CN3G75zOw80CFQgaaQodKbgFjA
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