Valve Bounce and Valve Spring Surge

[California Racer]

This is from the chapter 'Valve and Camshaft Engineering' page 74 in Hot Rod magazine's ''Cams Valves Ignition'. From their

Technical Library series of books published in '64.

It is excerpts from the book .'Valve Timing for Maximum Output'-Ed Iskenderian. Published in 1958.

Use damper inner springs or double springs to limit valve spring surge.

Valve spring surge causes early valve bounce.

Inertia of individual coils causes valve spring surge. Inconsistent valve opening and closing action will result.

This is just a little bit of what's in the chapter.

We should get our 'Valve Timing For Maximum Output' in about a week.

[bbodie52]

A sample of Corvair valve train specifications for 1963, 1964, and 1965 from the attached Chevrolet Corvair GM Heritage Center Specs indicates that in 1963 and earlier Corvairs, secondary valve spring inner damper springs were included only in the high performance engines. Beginning in 1964, the inner damper springs were included in all engines. 1960-1963 80 hp engines had no inner damper spring.

1963 CORVAIR VALVE TRAIN SPECIFICATIONS (Page 44)

1964 CORVAIR VALVE TRAIN SPECIFICATIONS (Page 60)

1965 CORVAIR VALVE TRAIN SPECIFICATIONS (Page 59)

Also read Valve spring problem - check before using

http://corvaircenter.com/phorum/read.php?1,629178



http://californiacorvairparts.com/index ... er=product

NEW VALVE SPRINGS SET
Part No. CC01227R
New set of 12 stock valve springs with inner damper springs for 1962-69 Corvair engines including turbos and 140's.
80 lbs. at installed height.


http://www.corvair.com/user-cgi/catalog ... IN&page=17

VALVE SPRINGS: Valve springs take a beating in a Corvair because the high temperature speeds fatigue. 1960-63 80 hp. (no inner damper) – These are way over stressed and should be replaced. each C1562 4 oz. 1960-69 High Performance with inner damper: STOCK each C1386X 4 oz. STOCK Set of 12 C1386XA 3 lbs./set
PERFORMANCE VALVE SPRINGS: These “high temp” springs are a must for the high temp of an air cooled head. C8619 springs are 115 -120 lbs. at installed height & are great springs for most stock & performance cams to 7000 RPM .475 lift. 12 Valve Spring Set C8619 2 lbs

Classic cars had a different way of doing things in the 1950s, 1960s and earlier, when compared to modern techniques utilizing sensors and computer technology to control fuel injection and ignition systems. There was a series of books that were published in the 1960s and 1970s that focus on basic principles of automobile design and function. These books covered basics associated with carburetors, ignition systems, suspension and brakes systems, etc. When I was a teenager I read through many of these books and they gave me a good understanding of the principles and functional designs that were common in the cars that I was interested in, including the Corvair. Once I read through these books, the shop manuals made a lot more sense to me as I began to understand how things function and what I was trying to accomplish in working on my Corvair. This series was published long ago (1960s-1970s) by Petersen Publishing Company, which was also associated with Hot Rod Magazine. With titles like Petersen's Basic Cams, Valves and Exhaust Systems, Petersen's Basic Ignition and Electrical Systems, and Petersen's Basic Carburetion and Fuel Systems, I was a teenager that found myself devouring much of the series to teach myself the basics that could be applied to most 1970s and earlier vehicles. The material in those books are now somewhat dated because of the change to computer-controlled electronic fuel injection and other sophisticated technologies that have been introduced in the subsequent decades. But I do feel a Corvair owner or any classic car owner could benefit from the material in these books. Many of them are listed as available on Amazon.com. If you would like to consider the possibility of reading through some of this material, the following link may help you to find what you're looking for. The cost of these books is low, and the investment in time that you might make in reading them may help you to develop a foundation of knowledge that will help you to leap ahead in your DIY maintenance efforts on your Corvair.

https://www.amazon.com/s/ref=nb_sb_noss ... automotive
ebay https://www.ebay.com/sch/i.html?_odkw=b ... c&_sacat=0

[California Racer]

Thanks Brad

There are Isky cam kits for Corvair in the one I'm reading now.

I will scan and post the pages with them.

Being that it's a '64 that shows the enormous amount of interest in the Corvair those first few years.

I think a lot of treadheads caught on to the uniqueness of it.

Corvairs were pretty hot if Isky came out with kits for it that quickly.

On the otherhand it is amazing to see the aftermarket stuff available in '60 and '61 already.

It is like 'how did they do that?'.

Those factory parts you showed would be the 'interchange' method of hopping up.

Using dealer parts to hop up and engine.

Good take on it by you.