Gross lift isn't measuring out right

[NHerron]

-Couldn't get the degreeing procedure out right no matter what method and that's when I noticed my gross VALVE lift.

I measured .405" on intake which should be .416" according to card.
I measured .387" on exhaust when should be .400" according to card.

*Double checked the cams for wear which came out fine. (Tallest point of cam minus the base)

*Lifters were shimmed correctly "where there was a slight drag between cam & roller"

*Dial indicator is parallel to valve (as good as I can eyeball it)

Does anybody know what's going on here?
Will this effect the degreeing procedure?

Thanks

 

[BogusSVO]

the cams you have may be boxed wrong.. check with the makers website and see if they have specs matching what you have measured.

 

[NHerron]

I spoke with CompCams & Forced Performance, they tell me the rocker arm ratio will change throughout the lift so +/- .010 doesn't concern him. Sounds right to me, but is this true?

They also pound me with 'centerline' method to be used to degree the cams. Everywhere on the internet says centerline isn't as accurate due to the aggressive ramp rate vs. gentle closing ramp? Not to mention, every 4G63 guide uses valve timing events.

Well I do it like they want and only had to adjust the exhaust cam 1 degree advanced. But (just to see) when I measure *degrees @ 0.050" lift my readings are at least 5* different than the cam card.

*I have the cam card with me but I checked the website anyway. My cams are Forced Performance/CompCams camshafts, here are the specs:
http://store.forcedperformance.net/merchant2/graphics/00000001/data/1012FP_FPCam2x.pdf

 

[TurboAnything]

fp1 cams have spec close to what you listed.

 

[NHerron]

fp1 cams have spec close to what you listed.

They are FP2X's, I know this for sure as I can see the markings they scribed on the camshaft itself. Thanks though.

Problem is now, that when I degree my cams to the "centerline" method, the other method gets out of whack (degree by valve timing events)

Does anyone have anything to say about degreeing cams? I wish more people knew about it, I'm tryin to learn it as much as I can but never hurts to hear from experience.

 

[TurboAnything]

Very strange. You are using solid lifter correct? I just can not understand why there would be a discrepancy in the timing events.

 

[LiquidX]

I encountered the same issue with Delta regrinds too. The max lift I measured was not what their card specs noted, this was with using solid lifters with the lash removed.

 

[NHerron]

Well it just doesn't add up mathematically. That is why I suspect I might be missing something.

For instance
-I measured INTAKE lobe lift (max height of lobe minus base circle) which comes to 0.241", spec is 0.242", cool. The rocker arm ratio is 1.72:1 so to find max valve lift you would do (.241 * 1.72 = .414") spec is .416". But when I ACTUALLY measure valve lift with dial indicator on valve retainer edge, I only get 0.405".

I'm pretty sure my lash is correct as I cannot fit a 0.001" feeler gauge AND the cam lobe base has a slight drag against the roller. I can stop the roller with my finger but I still feel the cam lobe trying to catch the roller.

Surely I must not be getting something. It's probably so dumb I'll be livid and relieved at the same time!

 

[chanley talon]

I encountered the same issue with Delta regrinds too. The max lift I measured was not what their card specs noted, this was with using solid lifters with the lash removed.

Fill me in here? Our lifters stock are hydraulic correct? Where can you get solid lift lifters? I am just curious cause i have delta regrind cams also.

I was wondering what you decided to do with those cams?

 

[LiquidX]

Fill me in here? Our lifters stock are hydraulic correct? Where can you get solid lift lifters? I am just curious cause i have delta regrind cams also.

I was wondering what you decided to do with those cams?

2 options, BLE lifters or make a set (I happen to be using home made solid lifters).

I ended up verifying TDC and that the cams were lined up via my gears. I may at some point down the road decide to go a different route with my cams due to various reasons so I'm not gun-ho on getting them dialed in now.

 

[NHerron]

I'm going to make sure my dial indicator isn't total crap tomorrow. The zeroing out function is hard to turn without it messing up the measurement but maybe it can't measure accurately either! This is tripping me out, I hope my dial indicator is just bad.

 

[keltalon]

Well it just doesn't add up mathematically. That is why I suspect I might be missing something.

For instance
-I measured INTAKE lobe lift (max height of lobe minus base circle) which comes to 0.241", spec is 0.242", cool. The rocker arm ratio is 1.72:1 so to find max valve lift you would do (.241 * 1.72 = .414") spec is .416". But when I ACTUALLY measure valve lift with dial indicator on valve retainer edge, I only get 0.405".

I'm pretty sure my lash is correct as I cannot fit a 0.001" feeler gauge AND the cam lobe base has a slight drag against the roller. I can stop the roller with my finger but I still feel the cam lobe trying to catch the roller.

Surely I must not be getting something. It's probably so dumb I'll be livid and relieved at the same time!

You are doing your math correctly and it is strange that the numbers are not matching the physical cam. My suggestion was also going to be for you to check the lifter and make sure they are completely bled and you may have to go ahead and install the cams straight up and drive the car so as to get the lifters pumped up after you take them out one by one and make sure they are all bled properly. And after a day of driving then degree your cams. I now it sounds unorthodox but this is what I had to do serveral times to ensure lifter sat where they needed to on base circle. Degreeing is one of those things its hard to figure out an issue someone my be having on the forum because there are so many variables to consider and not having physical engine in front of me its will be very difficult to pin point what the actual issue is and why the math is not adding up. If it makes you feel better I don't degree my cams anymore I install them straight up and take the car to the dyno and I tune my cam gears to acheive the power range, turbo spool that best fit my setup. I have seen guys spend hours degreeing their cams and when I am ask to help them tune the cam gears I end up changing there cam settings anyway so that the cams they purchase complement thieir set up this has worked better for me now for years.

 

[NHerron]

Thanks for checkin this out, keltalon. I spent a few days troubleshooting the whole degreeing thing and yes I was very tempted to just install straight up and adjust for power like you were sayin. I ended up using the centerline method only adjusted 1 degree retard, I think. I was using steel shims inside the lifter body by the way and the dial indicator was crappy, but still measures perfect. I also read that excessive base circle runout could have an effect on things but even that measured out correct. Maybe the solution will come to me in a few years realizing I totally missed a step. Haha. Anyway, thanks again everyone

 

[keltalon]

Thanks for checkin this out, keltalon. I spent a few days troubleshooting the whole degreeing thing and yes I was very tempted to just install straight up and adjust for power like you were sayin. I ended up using the centerline method only adjusted 1 degree retard, I think. I was using steel shims inside the lifter body by the way and the dial indicator was crappy, but still measures perfect. I also read that excessive base circle runout could have an effect on things but even that measured out correct. Maybe the solution will come to me in a few years realizing I totally missed a step. Haha. Anyway, thanks again everyone

Well don't forget to update the thread as to your progress. Hope everything work out and don't hesitate to pm me if you have any concerns