I'm assuming very few of you have actually seen the inside of a mod motor but the oil passages are very small. Than is why the manual recommends a low weight oil (5w20 or 5w30) depending on model year. My car says 5w30. When you use a higher weight oil 40w or 50w the oil does not pass through the motor as quickly and may not lubricate properly. You may not see any problems for years but I wouldn't try it.
Just something to think about.
FWIW I use 0w30.
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00 GT, MAC Offroad H, Steeda Pulleys & Timing Adjuster, 4.10’s, Flows w/turndowns, UPR shifter, UPR Pro Series LCA’s, Lakewood 70/30’s & 50/50’s, Weld Pro Stars, Kaenen Cobra R Hood, 253.8 RWHP/292.8RWTQ
12.91@101.93 (1.74 60ft)
M/M 100, 7085
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