Valve Spring Pressures for Endurance Build
03-11-2024, 01:38 PM
#1
Valve Spring Pressures for Endurance Build Hi,
Building up a 416 road race engine. Shooting for 7200 max RPM (but most of the time the limiter should be set at 6800). LS3 hollow intake and solid exhaust valves. Johnson 2116LSR lifters. Brian Tooley rockers and v2 trunnions.
I'm getting heads from Texas Speed with these valve springs...
Install Height: 1.810"
Closed Spring Pressure: 160 lb. @ 1.810" Installed Height
Open Spring Pressure: 415 lb. @ .660" lift
Maximum Spring Lift: .660"
Coil Bind 1.015"
I'm working someone from Brian Tooley Racing to design a custom cam for my road racing application and he said he'd like to see more spring pressure. They are suggesting 0.075 offset valve locks that'll push the springs pressures to 190 lbs closed and 403 lbs open (at 0.630 lift).
With the lift of 0.630, the 403 open pressure doesn't bother me. It's the 190 lbs seat pressure that "feels" high... but I'm new to these motors so maybe it isn't a big deal? I don't know what the downside of running a little extra seat pressure might be... I don't want to pop the head off the valve or something!
Thanks,
Sal
Building up a 416 road race engine. Shooting for 7200 max RPM (but most of the time the limiter should be set at 6800). LS3 hollow intake and solid exhaust valves. Johnson 2116LSR lifters. Brian Tooley rockers and v2 trunnions.
I'm getting heads from Texas Speed with these valve springs...
Install Height: 1.810"
Closed Spring Pressure: 160 lb. @ 1.810" Installed Height
Open Spring Pressure: 415 lb. @ .660" lift
Maximum Spring Lift: .660"
Coil Bind 1.015"
I'm working someone from Brian Tooley Racing to design a custom cam for my road racing application and he said he'd like to see more spring pressure. They are suggesting 0.075 offset valve locks that'll push the springs pressures to 190 lbs closed and 403 lbs open (at 0.630 lift).
With the lift of 0.630, the 403 open pressure doesn't bother me. It's the 190 lbs seat pressure that "feels" high... but I'm new to these motors so maybe it isn't a big deal? I don't know what the downside of running a little extra seat pressure might be... I don't want to pop the head off the valve or something!
Thanks,
Sal
03-11-2024, 02:30 PM
#2
You do not need 190lbs on the seat, especially with a hollow stem intake. To answer your question, installing your spring with 190 on the seat, isn't going to hurt anything. Just be sure to get a 3/8" pushrod in there.
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Che70velle (03-11-2024)
03-11-2024, 04:53 PM
#3
The pressure that needs to be raised, ALWAYS, is the seat pressure. It's almost impossible to have "too much", up to the point that the seats erode during a race or whatever the time unit of endurance is. (season, pass, 100k miles, whatever)
Valve "float" is NOT the valves getting "tossed" as the cam goes over the nose. It's the valves bouncing off the seat as they close. That behavior is UNBELIEVABLY destructive.
Follow BTR's advice. Either the offset keepers, or shims.
Valve "float" is NOT the valves getting "tossed" as the cam goes over the nose. It's the valves bouncing off the seat as they close. That behavior is UNBELIEVABLY destructive.
Follow BTR's advice. Either the offset keepers, or shims.
The following users liked this post:
ssanto (03-11-2024)
03-11-2024, 05:23 PM
#4
The pressure that needs to be raised, ALWAYS, is the seat pressure. It's almost impossible to have "too much", up to the point that the seats erode during a race or whatever the time unit of endurance is. (season, pass, 100k miles, whatever)
Valve "float" is NOT the valves getting "tossed" as the cam goes over the nose. It's the valves bouncing off the seat as they close. That behavior is UNBELIEVABLY destructive.
Follow BTR's advice. Either the offset keepers, or shims.
Valve "float" is NOT the valves getting "tossed" as the cam goes over the nose. It's the valves bouncing off the seat as they close. That behavior is UNBELIEVABLY destructive.
Follow BTR's advice. Either the offset keepers, or shims.