Think You Can Just Bolt Those New Heads On And Go .... Think Again !

most guys tend to run the valve springs that came on the cylinder heads they purchased,
in my experience, few even check valve train clearances until they run into problems.
most problems are rather easily avoided if you understand the need for checking valve train clearances, and degree in the cam, and talk to the cam manufacturers tech department guys, about your particular application, rocker ration, intended rpm range, and take their advice.
many guys seem to think that the tech guys just want you to buy more expensive components, or swap valve springs to boost their profits,
this is very rarely true, they don't want you to have issues/problems, as you'll bad mouth the product endlessly if you have a catastrophic engine failure, and they know that an extra hundred dollars in premium parts and careful clearance and valve train geometry checks can avoid that, making you far more likely to recommend their products to other potential buyers.
,that's one reason I was forced to learn how to do a great many things myself and had to acquire
a number of skills and a good many expensive tools,
as I got very tired of paying good money for sloppy half assed machine work,
and a we will get to your project when we get the time, and dealing with machine shops that think...
we damn sure won't put the time and effort into precise machine work that it requires in the vast majority of cases.


what you save initially, in lower price ,on any engine components
will more than likely be made up in the cost of required additional machining and time & effort added in required balancing/clearance work
you tend to get what you pay for, quality machine work and precision measurement and careful inspection processes take time and that costs money.
there is ALWAYS a compromise, made between quality and price
I learned that long ago,
“Quality is like buying oats: like:. If you want nice, clean, fresh oats, you must pay a fair price.
However, if you can be satisfied with oats that have already been through the horse ...
that comes a little cheaper.”:facepalm:

The following recommendations are from Erson Cams.
If you have questions, you can reach their tech department at 800-641-7920.
most cam manufacturers do extensive testing with each engine design to verify the limits and limitations of each engines valve train design, so it generally helps to talk with the cam suppliers tech department engineers.
cam lobe acceleration / de-acceleration rates have a large effect on the required spring load rates, as do rocker ratios and cam lobe size and lifter diameters.


sellecting valve springs, and setting up the valve train

How do you determine the spring pressure needed to keep the valves under control for a given lift, duration, and max rpm. It might take you several hours to read thru all the links and sub links but its time very well spent as it could save your engine from destruction and save you thousands of...
garage.grumpysperformance.com
Hydraulic Flat Tappet Camshaft: 110 lbs Seat pressure/250-280 lbs open pressure

Solid Flat Tappet Camshaft: 130 lbs Seat Pressure/300-325 lbs open pressure

Hydraulic Roller Camshaft: 130-140 lbs Seat Pressure/300- 355 lbs open pressure

Solid Roller Camshaft: (Minimum Safe Pressures DEPEND ON SEVERAL FACTORS)

Up to .600Ë valve lift: 200-235 lbs Seat Pressure/600 lbs open pressure

Over .600Ë valve lift: 250-280 lbs Seat pressure /100 lbs pressure for every .100Ë of valve lift
 
Last edited:
What really got my attention was the 2nd set of heads starting at 11:10 and going thru 13:50.
I would have never thought that a new set of heads could have been the reason that a valve hit the
piston when I checked the "piston to valve clearance" on one cylinder.

I had an intake valve hit the piston ....... Why did it happen ?
Crower and my local machine shop said I revved the engine too high. Maybe I did or maybe I didn't,
you can never check too many parameters !!!

Reminds me of a oil company commercial from the 70's

You can pay me now, or you can pay me later !

 
Back
Top