Разделить частоту обновления экрана и частоту обновления

Как мне можно поставить частоту цикла обновления мира фиксированную (120) и при этом не ограниченную частоту обновления экрана.

import pygame
import random

# settings
SC_W=1280
SC_H=720
PERFMON_SCALE = 1
BALL_RADIUS = 6

sc = pygame.display.set_mode((SC_W, SC_H))
clock = pygame.time.Clock()
pygame.init()
font = pygame.font.SysFont("arial", int(20 * perfmon_scale))
ball_count = 0
balls = []
class ballconstructor():
    def __init__(self,x,y,dx,dy,color,r):
        self.x = x
        self.y = y
        self.dx = dx
        self.dy = dy
        self.color = color
        self.r = r
    def draw(self,sc):
        pygame.draw.circle(sc,self.color,(self.x,self.y),self.r)
for i in range(10):
    balls.append(ballconstructor(random.randint(10, SC_W - 10), random.randint(10, SC_H - 10), random.randint(1, 3),random.randint(1, 3),(random.randint(0, 255), random.randint(0, 255), random.randint(0, 255)),ball_radius))
    ball_count +=1
while True:
    keys = pygame.key.get_pressed()
    sc.fill((45, 160, 185))
    clock.tick(120)
    fps = str(int(clock.get_fps()))
    fps = font.render("FPS: "+fps, 1, (255, 255, 255))
    ball_count_txt = font.render("BALLS: "+str(ball_count), 1, (255, 255, 255))
    if keys[pygame.K_SPACE]:
        for i in range(10):
            balls.append(ballconstructor(random.randint(10, SC_W - 10), random.randint(10, SC_H - 10), random.randint(1, 3),random.randint(1, 3),(random.randint(0, 255), random.randint(0, 255), random.randint(0, 255)),ball_radius))
            ball_count +=1
    for ball in balls:
        if ball.x + ball.dx >= SC_W or ball.x + ball.dx <= 0:
            ball.dx = -ball.dx
        if ball.y + ball.dy >= SC_H or ball.y + ball.dy <= 0:
            ball.dy = -ball.dy
        ball.x += ball.dx
        ball.y += ball.dy
        ball.draw(sc)
    perfbg = pygame.Surface((int(150*perfmon_scale),int(45*perfmon_scale)))
    perfbg.set_alpha(100)
    perfbg.fill((30,30,30))
    sc.blit(perfbg,(1,int(3*perfmon_scale)))
    sc.blit(fps, (3,int(3*perfmon_scale)))
    sc.blit(ball_count_txt, (3, int(23*perfmon_scale)))
    for a in pygame.event.get():
        if a.type == pygame.QUIT:
            quit()
    pygame.display.update()