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i have a c code 289 with rebuilt but stock bottom end. it has a stock cam with a 570 street avenger, torker 289 intake, stock rear end, afr 165 aluminum heads, and free flowing exhaust. i want to rev it past 4 thousand with my new 5 speed but i just dont know if it is safe to go above 4 thousand on a stock bottom end. thanks for any help!
 

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If you want some cheap insurance, buy a bottom girdle. That will help you to reach that higher rev point without worries.
 

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The stock 289 bottom end with ARP fasteners is good to 7000 RPM. With stock bolts I would easily take it to 5500. They are a strong engine - drive it!
 

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I know it'll do 6000 just fine, although I try not to take it over that. Occasionally, I'll accidentally hit 6100, and it takes it just fine. Using ARP studs, stock rods and crank, and forged aluminum pistons. I also have a Comp Cams XE262H with the correct springs, so I'm confident it'll hold up just fine. I know I could get so much more out of my car if it would just shift 2000 rpm later.
 

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Yep, the 289 is a certified screamer! If you want to get it even higher, put in some forged connecting rods and a proven valvetrain. Maybe even a steel crank. 7-8000 rpm shouldn't be too far off.
 
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