Valve springs
 

Hi Guys,
I'm looking for some confirmation, I know I've got a Chevy engine, but the question is universal for any engine, and I couldn't see where else to post (except as a discussion item on the dark side members group)
I built my engine using a comp cams 292H camshaft kit. I fitted edelbrock performer RPM complete heads (60459) should I have fitted the comp cam valve springs, or will the Edelbrock ones be O.K?
Thanks, Mark

I would use the valve spring as recommended by the cam grinder, not the head manufacturer.

Of course, if the Edelbrock springs match the specs required for the camshaft , they should be fine.

Your cam is a mild hydraulic, and so won't be too aggressive on the valvetrain.

I'd say they'll be fine but keep in mind that stock Edelbrock stuff comes with 7° retainers and locks.

As long as you have adequate spring pressures and checked for coil bind clearance you should be ok.

You might want to check them because some of the Edelbrock heads come with pretty good spring pressures and you would not want to knock a lobe of the camshaft. If it is a new camshaft make sure you use a special break in oil or you will have problems.

Good luck, Keith

Hi Keith,
from what information I can find, the edelbrocks have 100lbs seat pressure, and measure 1.44" OD, whereas the Comp Cams have 112lbs and 1.509" OD.
So, if anything the springs I am using are softer than spec.
I have the 10° comp cams retainers and locks, so I could change after my initial 500miles when I re-torque the heads, what do you think?
I used elf 5W30 synthetic as break in oil.
Mark

Springs are dimensional items. They neither know nor care whose name is on the package or what engine they are on. None of the popular brands make their own springs - they purchase them from one or two large spring companies - Peterson or Associated in most cases.

The pressures you quoted would be fine. But normally I avoid synthetics during break-in. No experience with Elf stuff over here though...

If you don't have an on-the-head spring compressor and a way to keep the valves shut, it won't be a fun job to change retainers and locks. You may want to look into a spring compressor that uses a rocker stud as a pivot point. You will also need a way to keep the valve from sliding down while you're trying to assemble.

I would agree that the springs that come with the heads are softer than spec. I don't like 100 lbs of seat pressure on anything with a hydraulic cam. I'd rather see something with 130-140 lbs seat. Remember, springs will lose some of their pressure after some heat cycles and I know that a lot of guys really like to spin their engines up on occasion. Valve float is not a good thing.

As for the synthetic oil as a break-in, I hope you haven't done any damage to the cam/lifters. If you didn't use any additive or a break-in oil like Brad Penn or Joe Gibbs, you have really threaded the needle if the break-in has went well. I would be checking the oil and filter for metal.

As for synthetic, never, ever use synthetic oil as a break-in oil. Not only is there no protection for the cam and lifters, chances are it will not let the rings seat either. I never recommend synthetic oil for any of my engines, even after long-term use, and I definitely wouldn't recommend it as an oil to use right after a rebuild/assembly.

Hopefully the low spring pressures that you have helped on the cam break-in. I would change the oil ASAP to a non-synthetic oil.

Another vote for not using synthetic oil in a new engine.

You must use a good quality mineral oil with a high ZDDP level, otherwise it's goodbye camshaft.

The Elf oil over here is pretty good-approx. 1200ppm
Immediately after break in, I changed to Valvoline VR1 20/50
Mark