When I dialed in my clevo crow cam it occured to me that we all seem to use No 1 cylinder for testing, setting true TDC then advancing or retarding cam position in relation to crank to acheive the desired timing.
So at every 90deg? crank rotation the next valve event for the firing order should occur.
So how accurate are the cams we purchase?
Should we check all cylinder valve timing events?
If they're out it would really screw up ones expected performance? What can you do if it is?
Has anyone ever bothered to check all 8?
When I dialed in my clevo crow cam it occured to me that we all seem to use No 1 cylinder for testing, setting true TDC then advancing or retarding cam position in relation to crank to acheive the desired timing.
So at every 90deg? crank rotation the next valve event for the firing order should occur.
So how accurate are the cams we purchase?
Should we check all cylinder valve timing events?
If they're out it would really screw up ones expected performance? What can you do if it is?
Has anyone ever bothered to check all 8?
Personally I dial it in on number one piston (i.e. advance/retard the camshaft in relation to the crank) and then check at random at least one other cylinder. You don't have to rezero the degree wheel but rather write down the events and remove/add either 90, 180, 270 degrees to get the correct results.
My old 351's cam was installed 4 deg advanced to get it to match specs. My 393's cam is installed 1.5deg advanced to get it to match specs. All the it needs to do is match the cam card.
Although cam grinding is good now days, always check. They are close dot to dot but not exactly correct. The cam in the 351 was a Crane/blueracer cam, the 393's cam is a comp cams one.
My old 351's cam was installed 4 deg advanced to get it to match specs. My 393's cam is installed 1.5deg advanced to get it to match specs. All the it needs to do is match the cam card.
Although cam grinding is good now days, always check. They are close dot to dot but not exactly correct. The cam in the 351 was a Crane/blueracer cam, the 393's cam is a comp cams one.
It would be easy enough to check all but I would only set the degree wheel once from No1 and check all inlet valve timings but turning the crank to the next 90deg and the next lobe lift should be at .050 lift @ No1 setting plus the 90deg I think?
I know all 8 were checked on mine with both crow cams I have used and they were both perfect.. My mech makes a habbit of checking everytime on all 8 cyl's because he has seen them out of whack before...
I know all 8 were checked on mine with both crow cams I have used and they were both perfect.. My mech makes a habbit of checking everytime on all 8 cyl's because he has seen them out of whack before...
And so what does he do if he finds that when the cam is correct at No.1 cylinder, its out on a say, No. 6? Adjust it to no 6? or split the difference?Personally I would like to know my cam is set up on the same cylinder as I set my ignition timing. No. 1.
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