Camshaft install

Tzar177

Member
Contributor
I've read some threads about needing to shim or buy new shims on new camshaft installs and i've read some that say its basically plug n play...just dropping in the new one and its done. Do I need to have it shimmed?
 
What cams are you installing?



I've read some threads about needing to shim or buy new shims on new camshaft installs and i've read some that say its basically plug n play...just dropping in the new one and its done. Do I need to have it shimmed?
 
Should be same base cricle as stock. See the online manual for specs and measurement instructions for valve clearance, if you don't have the manual I'll send you a link,let me know.If some shims are too tight and others too loose you can swap them with each other.



jspec intake and corkport exhaust
 
Should be same base cricle as stock. See the online manual for specs and measurement instructions for valve clearance, if you don't have the manual I'll send you a link,let me know.If some shims are too tight and others too loose you can swap them with each other.
That's what most people will do :)
 
Should they spin freely? How would I know if their too tight?

Look in the shop manual for valve clearance instructions and use a feeler
gauge to check the clearances. At the top of this forum is a link to the shop manual.

I would be surprised if they do not need some adjustment. You cannot be sure the base circle is the same as stock. The cam grind (lobe lift and duration) can affect the base circle diameter if the cam grinder starts off with the same size blank. Also valve seats can wear and affect the clearances.

Clifton
 
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they bolt in yes, but the lobes have different durations/sizes or w.e and thats why they need to be shimmed
so you dont have a valve a little open when it should be closed, etc.

i dont think you should have any problems though, most people dont even check the shims lol
 
FWIW, checking the valve clearance is really easy even if you've never done it before. All you need is a set of feeler gauges (costs less than $10). You just rotate the crank so that each cylinder in turn is at TDC with both valves completely closed, and then use the gauges to determine how much space is between the cam lobe and the lifter face for that cylinder. FYI the shop manual specifies .0089-.0116"

If you take measurements from all 16 valves and post them up, I'm sure someone here can give you some pointers on how to go about switching around or replacing shims.
 
when i installed my jspec cam shafts i didn't do any shimming or any measurements... been in there for a few years now no problems
 
Well I've already done the install and didnt measure up anything. Car idles and runs just fine. Once installed, the cams were pretty hard to rotate when trying to line up the timing marks
 
All you need to do to measure clearances is pull off the valve cover again. Worst case, you're out a $30 gasket. And yeah, they will be hard to rotate since at least one lobe is compressing a spring.

But, I would say that if you don't have any excessive noise coming from the valvetrain you're probably okay without reshimming them.
 
Stock cams should rotate easily, aggressive cams will click when the lobes hit the lifters, but still move easily.

Well I've already done the install and didnt measure up anything. Car idles and runs just fine. Once installed, the cams were pretty hard to rotate when trying to line up the timing marks
 
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