I degreed my cam using a Summit degree wheel,dial indicator, and piston stop. However I have check the lift on # 1 and # 6 lifter (USING SOLID LIFTER) and my lift is not where the manfacture says it should be. The cam card says EX-0.353.
I had 0.352 (Not bad at all) however on the intake side I was only able to get 0.345 max lift and the card say it should have 0.350. which will give me .005 less than what is advertised. I have recheck this over 10X and still in the same figures from .345-.3455 everytime. I was expecting to have 525/530 gross lift but now I will have 517.5/528. Which also reduce my net lift to 502/491.
How much Variance is acceptable when building a high performance engine?
Looking through some of UDHarold other popular cam that he recommend could it be possible to have received the wrong cam. The reason I say this is his SB276/284F10, 243/251 at .050, .518/.530 valve lift, and 110 LSA. Which is the exact same lift that I came up with.
The 517.5 lift on the intake is identical to his 276/284. But my cam card and Lunati box says I should have the 280/284F10.

Check the timing at .050 & see if it is 243 or 247 ;)

I setup the wheel and dial indicator to recheck my measurement and here is what I have. I'm using a 11" degree wheel so it take alot of guessing out of the equation.
Intake:
17.5 open
49.0 close
+ 180 = 246.5* advertised @.050/247*
Lift = 0.345 x 1.5 = 517.5 advertised .525

Exhaust
12
60
+ 180 = 252* advertised @.050 251*
Lift = .352 x 1.5 = 528 advertised 530

I also used a different lifter. My intake lift is shorter than whats advertised.
How will this affect performance and loss of horsepower across the power band?

That sounds like the 280 lobe.
Are you sure you have the indicator straight on the lifter?
If so unless the lobe has been redesigned or the lift number is a misprint -.005" at the lobe would be unacceptble to me.

Mike
Yes the indicator is on straight and I have taken the measurment too many times to keep getting the same exact reading.
if -.005 is unaceptable what type of problem or performance will I be losing?
Thanks:
Dave

Originally posted by DEEBOO:
Mike
Yes the indicator is on straight and I have taken the measurment too many times to keep getting the same exact reading.
if -.005 is unaceptable what type of problem or performance will I be losing?
Thanks:
Dave =
If the cam measures correct at .050, .100 & .200 etc. I highly doubt you could measure the difference power wise We are only talking about .0075 of lift.
Hell, you could put 1.6 rockers on, adjust the lash accordingly & pick up power.
I'm just not a fan of specs that far off, it makes me suspicious of the whole lobe profile.
Again this is assuming the lobe hasn't been redesigned
There are actually very good reasons to "flatten" the nose of a lobe which I will leave to Harold to explain ;)