Your .060" is a good number, but it is NOT between each coil!

 

Here's what CompCams says in one of their catalogs:

"With the valve at full lift, check the clearance between the coils. You need to maintain a minimum of .060" between the coils at this point."

How do you interpret that? Seems we're interpreting it differently.

Now that you bring it up, I'm going to check into this further to see if I can find a more clearly written recommendation. I don't want to pass along incorrect information as I'm sure you don't either.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

 

Here's what I found on Lunati's site, a diagram showing the .060" clearance between each coil.

http://www.lunatipower.com/Tech/Valv...pringTech.aspx

Do you have something that refutes this? It would be best to resolve this for the benefit of all.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

 

They're wrong.

Let me put it to you this way. Using your method and having .060" between each coil... how much clearance to coil bind do you have if you have 5 coils with .060" between each. Think about that for a second.

That must be a super low-lift cam!

 

Where you at man? You still looking for an answer? I saw you reply to another thread a couple hours ago, so I know you seen this.

Whoever uses this method to check coil bind... I wouldn't let them NEAR my engine.

 

Oh, so Lunati's wrong and you're right, okay - then why don't YOU go with that. Now you appear to be getting all stressed out because you aren't getting a response from me as quickly as you'd like. Please!

I've shown you the proof and still you presist. Now what's up with that??? This is NOT a competition where "I'm smarter than you" or "I know more than you do", I'm merely trying to help these guys, not compete. GEEZZZZ!

Truth be known, if you look at a spring, it has four openings between coils. Now if you go with .060" total, divide that by 4 - 1 for each opening. What you end up with is .015" clearance between each coil. Now go grab a feeler gauge and find one that's .015". Does that look like anything close to what you'd call SAFE? Common sense should tell you "NO".

Come on man, give it up. You're clearly wrong, so just accept it. You haven't lost your manhood because you're wrong. Just admit you're mistaken and move on. That's what reasonable and mature people do.

Now, bottom line, I'm not about to keep going back and forth with you on this issue. You are welcome to believe and do as you please, I just hope others don't follow your inaccurate information.

And I'm out.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

 

Ok, since you fail at the simple math question I asked you, I'll do it for you.

.060" between each coil times 5 coils = .300" total.

I'll take my PAC 1218s to use in this example.

Installed height = 1.800"
Max coil bind = 1.140"

That is .660" total lift to reach coil bind. A .600" lift cam will leave you with .060" coil bind clearance(660-600). PLEASE tell me where the hell I'm going to find .300" worth of extra clearance?!

To have .300" of left over space between the coils you would have to run a cam with .360" lift if you set them up at 1.800".

This is NOT a competition, it is an ATTEMPT to get people to NOT listen to what you said above.

And you think .015" between coils looks UNSAFE? I guess you didn't know that Beehives(and probably some others) actually STACK the outer coils together before the inside ones, did you? How safe would that LOOK? It helps to control spring surge, but I definitely don't want to get into that with you!




With all that said, I'll end with this...

Not all springs measure out like the manufacturer says they do. You need to check your own stuff, if possible. And the PROPER way to find the EXACT coil bind height is to STACK the spring.... yes, completely compressed, and measure that. Back off from that .060-.100"(or however much clearance you want) and run your lift up to that.

 

http://www.chevyhiperformance.com/te...ide/index.html

 

Like I said.

Crane Cams also gives the correct description. Comp and Lunati are way off.

 

From the Crane Cams article I was referring to in case someone was wondering.




What is a Valve Spring Coil Bind and how does it relate to spring travel and valve lift?
When the valve spring is compressed until its coils touch one another and can travel no further, it is said to be in coil bind. The catalog shows the approximate coil bind height for the various Crane Cams valve springs. To measure this you must install the retainer in the valve spring, then compress the spring until it coil binds. Now measure from the bottom side of the retainer to the bottom of the spring. This measurement is the coil bind height. This can be done on the cylinder head with a spring compression tool (part number 99417-1), in a bench vise, or in a professional valve spring tester.
Using the above figure, subtract the coil bind height "B" from the valve spring installed height "A". The difference "C" is the maximum spring travel. The spring travel must always be at least .060" greater than the full lift of the valve. This safety margin of .060" (or more) is necessary to avoid the dangers of coil bind and over-stressing the spring.

If coil bind occurs, the resulting mechanical interference will severely damage the camshaft and valve train components.