Hi-po camshaft - Valve bounce or clearance?

[lehiguy]

How will you prevent the valves from dropping in the head? Will it work on the last valve under the cowl?

Pressurize the cylinder with air. Most compression gauges have a coupler that will accept a standard air hose hookup. One other way (more red neck) is to use a section of CLEAN rope and feed it into the cylinder through the spark plug hole untill no more will go in. This provides a physical barrier to valves dropping in. Either way the piston needs to be at or near TDC on the compression stroke.

 

[fliphkd778]

I have all the tools, but what psi should one fill to?

 

[lehiguy]

I have all the tools, but what psi should one fill to?

I would assume that the more the better. If you manage to push one of the valves into the cylinder, the pressure would be lost. Leave it hooked up as you work and the pressure should stay consistent with whatever you have the regulator set to on your compressor.

 

[fliphkd778]

True, but what about too much pressure making the assembly rotate?

 

[Yspen]

Use this tool : Offset Ratchets

and http://www.jcwhitney.com/flexible-a...T2&zmam=15972153&zmas=18&zmac=129&zmap=27980G

 

[Yspen]

They finally arrived all the way from the US to South Africa

I really hope that valve clatter will be gone after they are installed

 

[lehiguy]

True, but what about too much pressure making the assembly rotate?

That can happen if true TDC is not achieved. If it is, it shouldn't be an issue.

 

[Yspen]

Update :

Tools used

Valve clatter is GONE .

 

[fliphkd778]

Good deal. 1. How long did it take to swap them all out? 2. Was the last spring up against the firewall difficult? 3. How many psi did you fill the cylinders to?

 

[Yspen]

1. How long did it take to swap them all out?

3 hours

2. Was the last spring up against the firewall difficult?

not more than the others

3. How many psi did you fill the cylinders to?

about 3 bar

 

[RockDoc]

Good to hear you got it sorted out

 

[Yspen]

Found this today : Print Page - New Valve Springs for '69 302...?

Flip you will be interested to see that the z28 valve springs and the vs 677 valve springs is the same thing :

Quote from that discussion :

The spring specs should be matched to the cam, and most aftermarket springs (including the "beehive" springs) are WAY stronger than the original stock springs. The beauty of the dynamics of the original Z/28 "30-30" cam "soft-action" lobe profile is that it used EXACTLY the same spring as all the 307/327/350 "grocery-getter" cars (P/N 3911068 single spring and damper - 90# closed, 190-200# open); Federal-Mogul #VS-677 is the same spring for less money.