Might be making progress?

[earlbrown]

They're a little weaker now just from age, but yes, they were borderline when new.
 A stock intake valve is 1.7" minus the stem sealing off the intake. That means you have roughly 2.18 sq" of valve face with 12.5PSI of stock boost trying to push it open. That will negate over 27#s of seat pressure...   Turn the boost up to 17 and you're now pushing an extra 37#s against the spring. Just by increasing the boost it's the same as losing 20# of spring preload

When you think about it like that it's pretty easy to see how 55#s of seat pressure can be a really crappy valvetrain setup.

Keep in mind back then the "fast" cars like 5.7 cameros, Vettes and 5.0 mustangs were running high 14's/low15's.  It wasn't that hard to destroy them in a so-so state of tune.

Hotrodding those cars required real money for not much where we could hang a throttle return spring on the wastegate rod, squish the FPR in a vise, add some race fuel and be in the 12's.

I guess it also helped that GM would warranty a few headgaskets and crate engines were available!!

[phil_long]

That makes a LOT of sense actually.  Its amazing that I've had my car for approximately 8 years or so, and I've learned the most within the last 6 months. 

[phil_long]

Renewing this thread because I'm finally getting around to purchasing some valve springs.  Any "special" things to look out for when I have the guy install these springs?  I read somewhere that a couple of them where a B-word to get to. Thanks

[Scoobum]

I've done a gazzilion sets. Make sure the springs, locks and retainers are clean and dry. Two people is easiest. One to compress the springs...the other to drop the locks in. Drop the bottom lock in first...let the spring come up a little to "seat" it...compress the spring again...then drop the top lock in. Use a pen magnet with the locks. I give 'em a love tap with a rubber mallet to make sure they're locked in. The rear two on the passenger side can be a whore.

[phil_long]

Lol.  Thats what i read before about those two. Thanks

[Steve Wood]

Might have to make a tool for those

[phil_long]

Thats no good.  Im so sick of this.  I dont get why shit just cant be straight forward and easy(like an injector swap).  Lol.  Im having other issues, but not sure if i should start a new thread or not.

[earlbrown]

those overhead valve spring compressors with the wheel on top will clear #6 and it only takes one person to do the job.

Just make sure the piston is at TDC while you have the springs off. IF a spring happens to drop down below flush DO NOT turn the crank to push it back up. use a hose to suck the valve back up into the head (much like that time Cartman had to suck the sea people he bought through a hose).

[Steve Wood]

I've always just hooked an air hose to the cylinder I was doing and kept the valve in place with air pressure

[phil_long]

Ah, air tools.  That sounds like a disaster.  The guy who's doing the work(i plan to help if i can) sold Charles his GN.  He did all the work on it, but I'm not sure he went through the "proper" fundamentals throughout Charles car.  I mean, his GN is stout, but its mismatched IMO. Anywho, I dont think he ever changed out the valve springs.  He put the GN1 heads on there, so i dont think he ever had to do it(change the actual springs).  Im sure he'll figure it out though.  The guy who did my timing chain is who I'd prefer, but a part of me feels like he don't want my business.  Oh well

[Steve Wood]

not a tool, just a fitting that screws into the spark plug hole that you connect to an air hose.  Simple as it gets.

the GN heads (assuming we are talking about aluminum heads) probably had new springs on them.  On the other hand, they will slow a near stock GN down unless one runs more boost, compression, and/or timing

[Grumpy]

the GN heads (assuming we are talking about aluminum heads) probably had new springs on them.  On the other hand, they will slow a near stock GN down unless one runs more boost, compression, and/or timing

ok tid bit of info.. Even why BUYING new heads (alum or steel) Check the damm springs !!! I have found a lot of mis matched stuff over the years. So don't "ASSUME" 

Oh if ya do this yourself get the spring tool with the round thing on top.. When ya get to the hard ones you can take the top off and use a wrench.. Makes things a little easier.
 

[Forzfed]

not a tool, just a fitting that screws into the spark plug hole that you connect to an air hose.  Simple as it gets.

That's the best way to do them.

You can also make more power with lighter springs and titanium retainers.  But I don't think anyone here is making that kind of power or pulling high rpms to take advantage of them.

[earlbrown]

You can also make more power with lighter springs and titanium retainers.  But I don't think anyone here is making that kind of power or pulling high rpms to take advantage of them.

The most cost effective way to get rid of sprung weight is to go beehives. The difference in mass between steel and Ti on those is marginal.

[Steve Wood]

the GN heads (assuming we are talking about aluminum heads) probably had new springs on them.  On the other hand, they will slow a near stock GN down unless one runs more boost, compression, and/or timing

ok tid bit of info.. Even why BUYING new heads (alum or steel) Check the damm springs !!! I have found a lot of mis matched stuff over the years. So don't "ASSUME" 

Oh if ya do this yourself get the spring tool with the round thing on top.. When ya get to the hard ones you can take the top off and use a wrench.. Makes things a little easier.

seems like I used a crow's foot wrench once on the hard ones