L82 valve Springs
Thread Starter
Intermediate
Joined: Aug 2020
Posts: 37
Likes: 2
From: New Orleans
L82 valve Springs
Just got a 77 L82 with 110k. Gonna replace the valve seals, and thinking why not new springs…not expensive and after 47 years and 110k it can’t hurt. Can anyone recommend a like OEM spring? You would think this is easy like on my C5Z, but not at all. Lot’s of measurement. No cam or head mod, just long tubes and EFI. Can anyone say “buy these”? I see some at Summit and other places, but they usually mention Cam changes. Any help would be appreciated.
Le Mans Master
Joined: Mar 2004
Posts: 7,502
Likes: 1,510
From: Little Rock AR
I would not change them. If you do want to change them anyway, you want to use Enginetech ERV880. They are stock replacement pressure to save your cam and lifters. Probably come in a pack of 4 so you need to order 4 packs. Best deal around.
Thread Starter
Intermediate
Joined: Aug 2020
Posts: 37
Likes: 2
From: New Orleans
Le Mans Master
Joined: Mar 2004
Posts: 7,502
Likes: 1,510
From: Little Rock AR
The stock original springs are soft, work great and easy on the cam and lifters. Motor oil is not what it once was and cams are going flat because of it even with the soft springs. Use good "high zinc" conventional oil (like Valvoline VR-1 10W-30) and keep the old springs in there is my advice. Obviously others are in agreement.
One more thing....You will see a lot of so-called "Z/28" replacement valve springs out there. Do not use them. They have more pressure than stock and you just don't need, or want it. They were NEVER used in a production engine by GM, so this is not well understood. The "Brown stripe" -142 "Z/28" springs were designed to be used on the -140 GM short track, first design "off-road" racing cam. If you want to get a few more RPM, up to say 7000 you might want to try them, but your engine would not need these at all.
One more thing....You will see a lot of so-called "Z/28" replacement valve springs out there. Do not use them. They have more pressure than stock and you just don't need, or want it. They were NEVER used in a production engine by GM, so this is not well understood. The "Brown stripe" -142 "Z/28" springs were designed to be used on the -140 GM short track, first design "off-road" racing cam. If you want to get a few more RPM, up to say 7000 you might want to try them, but your engine would not need these at all.
Thread Starter
Intermediate
Joined: Aug 2020
Posts: 37
Likes: 2
From: New Orleans
Great info. Yep..... that was my#1 concern is more pressure or too stiff. And yes, I use a zinc additive (suggested on this forum) . Sold...... will not change unless damaged and then will go with the one you recommended. Thanks for the info.
Le Mans Master
Joined: Mar 2004
Posts: 7,502
Likes: 1,510
From: Little Rock AR
One more thing I failed to mention.....if you see the exhaust valve retainers are thicker than the intake valve retainers, it is because you have rotators on the exhaust valves. In many cases the exhaust valve springs are actually shorter to make up the difference in height. Not always that way but usually. Can be a lower spring height pocket.
My advice if you feel the need to replace springs would be to delete the rotators and run all the springs the same length with the same retainers.
My advice if you feel the need to replace springs would be to delete the rotators and run all the springs the same length with the same retainers.
