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Crower cam book
- Thread starter Joe
- Start date
flying fish
Well-known member
Part Number/Work Order Number 52238
Engine Application 400-455 BUICK
Grind Number 270HDP
ADVERTISED CAMSHAFT SPECIFICATIONS:
INTAKE: Duration: 270º Lift: 0.464 Clearence Hot: 0
EXHAUST: Duration: 276º Lift: 0.488 Clearence Hot: 0
The specifications listed above are based on a rockerarm ratio of 1.6 IN
1.6 EX
RECOMMENDED VALVE SPRING INFORMATION:
Part # 68302-1 Single X Dual Triple
Approximate spring pressure: valve closed: 085/095 LBS.
valve open: 240/250 LBS.
-3.0
ATDC -9.0
BTDC
ABDC
33.0 43.0
BBDC
The information below is for degreeing cam only. Correct only at .050" tappet lift.
INTAKE Opens: -3.0 ATDC
Closes: 33.0 ABDC
EXHAUST Opens: 43.0 BBDC
Closes: -9.0 BTDC
LOBE SEPERATION 112º
Duration at .050" Intake: 210
Exhaust: 214
LOBE LIFT Intake: 0.29
Exhaust: 0.305
If using "Lobe Center" method of degreeing, cam should be installed on an intake centerline of: 108º
NOTES:
Engine Application 400-455 BUICK
Grind Number 270HDP
ADVERTISED CAMSHAFT SPECIFICATIONS:
INTAKE: Duration: 270º Lift: 0.464 Clearence Hot: 0
EXHAUST: Duration: 276º Lift: 0.488 Clearence Hot: 0
The specifications listed above are based on a rockerarm ratio of 1.6 IN
1.6 EX
RECOMMENDED VALVE SPRING INFORMATION:
Part # 68302-1 Single X Dual Triple
Approximate spring pressure: valve closed: 085/095 LBS.
valve open: 240/250 LBS.
-3.0
ATDC -9.0
BTDC
ABDC
33.0 43.0
BBDC
The information below is for degreeing cam only. Correct only at .050" tappet lift.
INTAKE Opens: -3.0 ATDC
Closes: 33.0 ABDC
EXHAUST Opens: 43.0 BBDC
Closes: -9.0 BTDC
LOBE SEPERATION 112º
Duration at .050" Intake: 210
Exhaust: 214
LOBE LIFT Intake: 0.29
Exhaust: 0.305
If using "Lobe Center" method of degreeing, cam should be installed on an intake centerline of: 108º
NOTES:
flying fish
Well-known member
Joe
I cannot help you with a cam selection. I surely suggest that you gather some info and present this info either to the guys on this website or to your favorite cam tech.
I have tried a lot of different camshafts on a lot of different engines the last few years.
Whether it be trying to help get guys off the corner, or trying to help the same guys with traction control. Or, how can I swing the exact prop with 2 degrees more pitch to the same governed RPM and still Idle up to a limb line. Really makes me scratch my head.
I have wasted most my extra money the last few years experimenting with your exact question. Need any billet roller pieces?
Here are some suggestions as to info to gather and some concerns.
First concern is can you get by with 500ish lift without having retainer to guide issues. Also, what is your piston to valve with your present camshaft?
Now, what size is your motor? What is the static compression ratio. What is your targeted max RPM? What head are you using and what is the flow data on that in particular head? What intake manifold you using? What carburetor are you running.Are you running this engine in a direct drive application or are you using a reduction unit.
What do you do with this boat? Is idle quality an issue or just swinging the most pitch your concern? Just like with aviation, it is going to be a trade off.
I do not need to know this info asked.
I cannot help you with a cam selection. I surely suggest that you gather some info and present this info either to the guys on this website or to your favorite cam tech.
I have tried a lot of different camshafts on a lot of different engines the last few years.
Whether it be trying to help get guys off the corner, or trying to help the same guys with traction control. Or, how can I swing the exact prop with 2 degrees more pitch to the same governed RPM and still Idle up to a limb line. Really makes me scratch my head.
I have wasted most my extra money the last few years experimenting with your exact question. Need any billet roller pieces?
Here are some suggestions as to info to gather and some concerns.
First concern is can you get by with 500ish lift without having retainer to guide issues. Also, what is your piston to valve with your present camshaft?
Now, what size is your motor? What is the static compression ratio. What is your targeted max RPM? What head are you using and what is the flow data on that in particular head? What intake manifold you using? What carburetor are you running.Are you running this engine in a direct drive application or are you using a reduction unit.
What do you do with this boat? Is idle quality an issue or just swinging the most pitch your concern? Just like with aviation, it is going to be a trade off.
I do not need to know this info asked.
flying fish
Well-known member
Joe
I did some reading on some of your posts. I read where you lost a distrubitor gear and cam gear on a 5 year old engine. I also saw where you have a dish piston and a thick head gasket. Also, you have a reduction unit and you are wanting to be able to run more pitch to the same governed RPM if possible.
Another bit of info I gathered is that you presently have a camshaft that has an advertised duration of 270 In. & 276 Ex. w/112LSA. This camshaft has a duration also @.050 tappet lift. The duration @.050 is 210 In. & 214Ex. Still 112 LSA
You mentioned that you are thinking about a camshaft that has a duration of 231 In.
and 234 Ex. w/110LSA. Something makes me think you are eyeing a camshaft with 231/234 duration @.050 tappet lift w/110 LSA. If these new cam #'s are actually @.050 #'s then this camshaft is way bigger than your present camshaft.
So, theoritically if you can get the extra air in your engine you could possibly see 10 hp gain for every 6 degrees extra in duration on the camshaft you are looking at. This 455 cid engine could possibly absorb the bump stick you are looking at quite nicely if it is in fact a 231/234 @.050 cam with a 110LSA. Very nicely actually.
Only couple things I read that would reallllly bother me personally.
#1) You lost a cam and distrubitor gear on a 5 year old engine. The chewed up, really fine pieces of metal went where?
#2)You have a loose quench piece. Tightening the quench is worth say 10 horse if you raise the compression 1 full point. My question here would be. Is it worth raising the compression possibly inviting detonation problems? Timing is a cool tool for manipulation.
There is a point where you will really see a trade off when increasing camshaft duration on a chosen engine.. You are possibly close if @.050#'s. Lots of cubes.
If I were looking at a camshaft with @.050 #'s like the ones you posted and also with a 110 LSA. I would really be excited about getting my 5 year old engine torn down and ready to re-assemble with a new bump stick. JMO-
I did some reading on some of your posts. I read where you lost a distrubitor gear and cam gear on a 5 year old engine. I also saw where you have a dish piston and a thick head gasket. Also, you have a reduction unit and you are wanting to be able to run more pitch to the same governed RPM if possible.
Another bit of info I gathered is that you presently have a camshaft that has an advertised duration of 270 In. & 276 Ex. w/112LSA. This camshaft has a duration also @.050 tappet lift. The duration @.050 is 210 In. & 214Ex. Still 112 LSA
You mentioned that you are thinking about a camshaft that has a duration of 231 In.
and 234 Ex. w/110LSA. Something makes me think you are eyeing a camshaft with 231/234 duration @.050 tappet lift w/110 LSA. If these new cam #'s are actually @.050 #'s then this camshaft is way bigger than your present camshaft.
So, theoritically if you can get the extra air in your engine you could possibly see 10 hp gain for every 6 degrees extra in duration on the camshaft you are looking at. This 455 cid engine could possibly absorb the bump stick you are looking at quite nicely if it is in fact a 231/234 @.050 cam with a 110LSA. Very nicely actually.
Only couple things I read that would reallllly bother me personally.
#1) You lost a cam and distrubitor gear on a 5 year old engine. The chewed up, really fine pieces of metal went where?
#2)You have a loose quench piece. Tightening the quench is worth say 10 horse if you raise the compression 1 full point. My question here would be. Is it worth raising the compression possibly inviting detonation problems? Timing is a cool tool for manipulation.
There is a point where you will really see a trade off when increasing camshaft duration on a chosen engine.. You are possibly close if @.050#'s. Lots of cubes.
If I were looking at a camshaft with @.050 #'s like the ones you posted and also with a 110 LSA. I would really be excited about getting my 5 year old engine torn down and ready to re-assemble with a new bump stick. JMO-
Flying fish,Your right it is @.050,I was really tired when I was posting 
The problem was in the oil pump,it`s on the timing cover on buicks. it happened so quickly the shavings are still on the timming chain and front of the oil pan.i am tearing it all the way down and cleaning every thing any way. The bearings all look new still,I got really lucky. I`m down to a choice of the cam i posted in the other thread and one a little smaller, 499 lift intake and exhaust 232 duration @.050 on both as well. just not sure,the quench was originally tighter,so I`m gunna try it.i allways run my trimming pretty conservative,so to avoid detonation
The problem was in the oil pump,it`s on the timing cover on buicks. it happened so quickly the shavings are still on the timming chain and front of the oil pan.i am tearing it all the way down and cleaning every thing any way. The bearings all look new still,I got really lucky. I`m down to a choice of the cam i posted in the other thread and one a little smaller, 499 lift intake and exhaust 232 duration @.050 on both as well. just not sure,the quench was originally tighter,so I`m gunna try it.i allways run my trimming pretty conservative,so to avoid detonation