Any way to find camshaft lift & duration with camshaft already in engine.

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Claude C

Twin '66 Cudas
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Title says is...Wondering if you can get this info if cam is already in running engine. Engine had cam replaced during rebuilt but that was before I got the engine. Any help appreciated. Thanks- Claude
 
Maybe yes;
Lift is easy to check
Duration is not, but can be done by degreeing the cam.

Some cam lifts proclaim the cam that they appear on.
Like a 292/292 cam... the duration is known and there are not a lot of contenders in that arena.
Others like the 268/276; everybody has one and the lifts are all over the place, so you just can not guess on this one.

Some guys, not me, can guess the size of the cam by the relationship of idle-speed to manifold vacuum, and others by the relationship of idle-lope and idle- rpm; also not me.

The only sure way is to degree it and measure the lifts.
 
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Title says is...Wondering if you can get this info if cam is already in running engine. Engine had cam replaced during rebuilt but that was before I got the engine. Any help appreciated. Thanks- Claude
You can if you have a degree wheel and dial gauge setup. It depends on how accurate you need to be but you can get pretty damn close. You will need to find TDC with the degree wheel and you can use a piston stop for that. You will use the gauge setup to measure the cam. I would just pull the rockers (or a rocker) and place the gauge on the top of the pushrod starting on the base circle.
 
There's no maybe involved. Get a valve cover off, get the belts off. Get the fan off. Knock the crank pulley off. Stick a degree wheel and dial indicator on it and have at it. If it was mine, I'd even get the radiator out of the way. Makes it a lot easier.
 
print yourself a degree wheel (https://static.summitracing.com/global/images/prod/large/SUM-G1057.jpg , https://lh3.googleusercontent.com/p...tvXvC-4SbPAxeiDqIxZwa1WHVBldBK4MaRiwp42TXM3HW) and glue it onto an old Nickleback album. Use piston stop and find TDC and set it. Use a dial indicator on a pushrod (dont use on a rocker as the spring could 'deform' the lift due to hydraulic lifter preload). Your lift will be pretty close to dead nuts by using a 1.5:1 ratio and then you can determine the duration by TDC and lift @ .050 per a cams spec. Use a intake and exhaust to see if its a split duration cam.
 
print yourself a degree wheel (https://static.summitracing.com/global/images/prod/large/SUM-G1057.jpg , https://lh3.googleusercontent.com/p...tvXvC-4SbPAxeiDqIxZwa1WHVBldBK4MaRiwp42TXM3HW) and glue it onto an old Nickleback album. Use piston stop and find TDC and set it. Use a dial indicator on a pushrod (dont use on a rocker as the spring could 'deform' the lift due to hydraulic lifter preload). Your lift will be pretty close to dead nuts by using a 1.5:1 ratio and then you can determine the duration by TDC and lift @ .050 per a cams spec. Use a intake and exhaust to see if its a split duration cam.

Yeah that will make good use of one of their albums, cause spinnin it on a turntable ain't.
 
Title says is...Wondering if you can get this info if cam is already in running engine. Engine had cam replaced during rebuilt but that was before I got the engine. Any help appreciated. Thanks- Claude
Here's a great video to show you how.
 
print yourself a degree wheel (https://static.summitracing.com/global/images/prod/large/SUM-G1057.jpg , https://lh3.googleusercontent.com/p...tvXvC-4SbPAxeiDqIxZwa1WHVBldBK4MaRiwp42TXM3HW) and glue it onto an old Nickleback album. Use piston stop and find TDC and set it. Use a dial indicator on a pushrod (dont use on a rocker as the spring could 'deform' the lift due to hydraulic lifter preload). Your lift will be pretty close to dead nuts by using a 1.5:1 ratio and then you can determine the duration by TDC and lift @ .050 per a cams spec. Use a intake and exhaust to see if its a split duration cam.
Why Nickleback? :lol:
 
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