Thread: Push rods too short?

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Originally Posted by JustaChevyGuy

That is an idea that I have not had time to do as of yet but will this weekend -

I was reviewing the earlier post:

"you posted that the cam was .498 ex lift---that will be at the valve of course and with a 1.5 rocker means that cam lift will be aprox .332------ put an indicaror on the lifter and see how much lift your getting"

Just out of curiosity - if I am measuring from the pushrod side, I would look for .498 - yes?

And Pat, I have been trying to find the time to call you around 9am my time so that it's around your lunch, I just have not had the time to do that from work - seems like something always comes up and by the time that I look at the clock, it's closer to 3:00 your time... By the way, I checked out your site, very nice!

thanks both sites are up still wounld of like them abit better but they do the job . show some of the many of the engine i have built and machine work i can do at my shop. well about 4:30 i start to clean up so no machines are running so i should have some time around 4.30

pushrod side will be the .332----if it is signifintely different(less) you will have found that lobe is worn----------






and your just today reading post #16 that I made on 3-16 ?

No -Jerry, just have not had time to do it as of yet...

To confirm, the pushrod side will be .332? I guess I am not getting the math in my head...

Thanks again for the help, don't mind learning -

Originally Posted by JustaChevyGuy

No -Jerry, just have not had time to do it as of yet...

To confirm, the pushrod side will be .332? I guess I am not getting the math in my head...

Thanks again for the help, don't mind learning -

at lobe or on head push rod side would be .332 at valve stem side threw rocker if 1.5 so net lift 498

332 x rocker arm 1.5 = 498 lift or with a 1.6 rocker 332 x 1.6 = 531.2

and thanks Pat, you Rock!

Originally Posted by JustaChevyGuy

and thanks Pat, you Rock!

yes... i know

many times it is just as easy to just take the lifter out and look at lobe many times the lifter will be bowled out cam lobe will be shiney and nose will be round side to side and will have ramps ground off the fast way is look at a good lobe you should easly tell just looking down the lifter bore. if you do not have a 1 inch dail gauge to measure the travel of push rod . if lets say it a ex side lobe you think is bad you use a good ex lobe back off rocker arm. crank engine by hand. take out spark plug engine will be easser to turn. turn the engine till you on the base circle off cam now mark push rod with a fine tip sharpy marker by head make a line in the push rod . that can be copyed easly by guild plate wiil do .now crank till your at full lift mark push rod now you will have two marks on push rod and almost to very close to .332 now check the bad lifter side marking the push rod the same way as you did the good side back off rocker . check lifter at base circle and crank to max lift now mark push rod you will have two marks like test push rods . now take push rods out a look at your marks or you could messure them from the center line of mark to mark both should be about .332. now if the good push rod it lets say close to 300or 360 and bad lifter side is only 200 then you know it is cam time

ok, I think that I have it - where the disconnect for me is - the Comp spec card says Gross Valve lift is .498 Exhaust, are they making the assumption that you are going to use 1.5 rockers? Lobe lift does say .332 Exhaust....

Here is how it reads just so you see what I am seeing:

These Specs are for cam installed @ 107.0 intake center line

Duration @ .050 Intake 226 Exhaust 234
Lobe Lift .3200 .3320
Lobe separation 111.0

Originally Posted by JustaChevyGuy

ok, I think that I have it - where the disconnect for me is - the Comp spec card says Gross Valve lift is .498 Exhaust, are they making the assumption that you are going to use 1.5 rockers? Lobe lift does say .332 Exhaust....

Here is how it reads just so you see what I am seeing:

These Specs are for cam installed @ 107.0 intake center line

Duration @ .050 Intake 226 Exhaust 234
Lobe Lift .3200 .3320
Lobe separation 111.0

post #37 i showed what lift would be with a 1.5 rocker or a 1.6 it is the rocker that add to cam lobe lift the cam has a lobe lift of .320 x by 1.5 or 1.6 what ever rocker Ratio must be added to cam lobe lift