I'm in the process of rebuilding my 289. I plan to build the bottom end tough so later if I want to up the power I don't have to rip it all apart and replace good parts. My question is what kind of power and RPM can the stock 289 connecting rods handle? If used I would upgrade the fasteners to something stronger, probably ARP.
1965 289 Connecting Rod Questions
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zookeeper
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What's your budget? Stock Ford rods are fairly strong, mostly due to the short stroke, and with good bolts, they're fine for some pretty healthy power. Having said that, if you have the money, there are better rods, but rods don't make horsepower. If you've got a limited budget, and are looking to make power, spend it on heads instead. Joe Sherman is an engine building wizard who is of the opinion that your money should go into the carb-intake-heads-exhaust and cam area, since that's where the power is. Who cares if you grenade a cheap bottom end? Chances are you can save the aluminum head easily and cheaply, and spend a few hundred bucks for another cheap bottom end and you're back in business. Hard to argue with a guy who builds 800+ hp Ford small blocks that don't need bottles or boost to get those numbers.
like the others have said, the 289 rod needs very little prep to handle a lot of power. just upgrading the stock 5/16 rod bolts to the same size arp bolt is a good step. there are a couple of things you can do on the cheap to make things even better though;
1: polish the rods. if you look at the rods you will see the mold parting line. you want to polish that down level with the rest of the beam. you also want to remove all sharp edges to remove stress risers. this you can do yourself with the same polishing rolls you find in a head porting kit. they dont need to be a mirror finish, but you need to use the finest grit available for the final polishing.
2: upgrade not only the rod botl material, but the size as well. some people will tell you you change to the same 3/8 bolts that the hipo 289 and boss 302 rods used, DONT DO IT. the standard rod does not have enough material to do that, BUT it does have enough to go to an 11/32 rod bolt. you will have to have a machine shop enlarge the holes for you. have it done when you have the rods rebuilt and balanced. arp does have the 11/32 rod bolts available. as i recall they are the same rods bolts as used on AMC V8's from the 70's.
1: polish the rods. if you look at the rods you will see the mold parting line. you want to polish that down level with the rest of the beam. you also want to remove all sharp edges to remove stress risers. this you can do yourself with the same polishing rolls you find in a head porting kit. they dont need to be a mirror finish, but you need to use the finest grit available for the final polishing.
2: upgrade not only the rod botl material, but the size as well. some people will tell you you change to the same 3/8 bolts that the hipo 289 and boss 302 rods used, DONT DO IT. the standard rod does not have enough material to do that, BUT it does have enough to go to an 11/32 rod bolt. you will have to have a machine shop enlarge the holes for you. have it done when you have the rods rebuilt and balanced. arp does have the 11/32 rod bolts available. as i recall they are the same rods bolts as used on AMC V8's from the 70's.
