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Discussion Starter #1
Due to a recent change in tire size my motor is seeing more RPM's than I originally thought. I changed from 33x15x15 high growth tires to 32x15x15 tires. The motor is an sb2.2 small block with a relatively mild cam and is now going through the stripe at 9,000 rpm's. It is pulling hard and not at all laying over, but I am concerned that the rpm's are too much for the heavier weight of steel rods. It's a Dart block, with a callies magnum crank standard rod journals, Oliver Billet Steel rods, and Diamond gas ported pistons. Any input is appreciated.
 

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Long Live The King
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You typed " Oliver Billet Steel rods "

Just check with them on the rod bolts you're using. Good thing you didn't type " Scat"

btw..do you know how many grams the rods weigh? ...and the pins?

G :D
 

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Considering a lot of Pro Stock are using steel rods now and NASCAR has always used them, I would think you'd be fine.
 

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Discussion Starter #5
Don't know the gram weight on those rods, but they are not the lightened rods. They are the standard Oliver 6 inch billets. I am using ARP 2000 bolts.
 

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pig hunter
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sbc rod and 9000rpm, should be o.k. back in the day, we would spin chevy pink rods with good bolts to 8000+
 

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I think my sb2.2 will spin to 9200 especially with the mess I made when sizing the heads. I've been on the phone with every high end rod company from dyers, oliver, callies, lentz, carrilo, and all of them say that their rod won't have a problem with 9500 rpm even with my 700 gram piston/pin package. They all stress highly that the bolt needs to be of the highest quality. Either a Carr, A1, or best ARP bolt. The bolts I've found are normally about 400-600 for the set, this is for a 3/8 bolt. Check what bolt you have, call Oliver and give them your weights, stroke, and rpm and they will be able to tell you if your hurting anything. They are really honest with what their rods can and cant handle
 

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All motor wannabe
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the rods will be fine nascar has been running steel rods forever and they spin those long term for lot of mileage before a tear down. The rod bolts as it has been already said will be the biggest thing you need to keep an eye on/get a good set. as mentioned above Carr A1 of ARPs are top quality stuff. I personally like Carr
 

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I'm not turning mine 9000 but do turn it 8500. Oliver billet rods with WSB bolts with 2.000 journals. Rods weigh right around 600 grams pistons weigh 400 grams and pins are 100 grams.
 

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Don't know the gram weight on those rods, but they are not the lightened rods. They are the standard Oliver 6 inch billets. I am using ARP 2000 bolts.
I might be wrong...but if they are in fact Olivers. I'm pretty sure they never came with ARP2000 bolts...standard or as an upgrade.
 

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Its not as much as about rpm than it is about peak piston speed and reciprocating mass , no big deal to spin something 9000 rpm with a light load and only 3.25", 3.5" stroke. But increase piston speed and weight and 9000rpm becomes a problem. It all depends on what you have.
 

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sounds pretty common setup[...

duno why there would be a doubt if the bolts and rods are legit pieces


all of these calculations will center around ultimate piston speed and weight of the parts...

calculate the piston speed if you wanna really know....
 

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Discussion Starter #15
The rods are indeed Oliver Billets. I purchased them direct and ran them very little in a conventional headed motor first and I bought new ARP 2000 bolts when I assembled the Sb2 motor. Bore is 4.125 and stroke is 3.750. Pistons are gas ported Diamond with .927 pins. I am shifting at 8300. The more I think about it I think it will be ok, as it hits 8900-9000 just momentarily at the stripe. I have already put 10 runs on it since the tire change and I check lash and spring pressures often. I am also fighting some chassis issues since the tire change with the tires dead hooking and pulling the motor way down. I am figuring that out and the motor may see less rpm's when I do. I have too tight a rear spread in the 4 link, and the bottom bars have too much pitch. That will be fixed before my next time out. Thanks for all the input.
 

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Go Phuck youself
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All depends on the motor balance job. Bal. is the key todays 4340 rods are kick ass as someone stated before pink chevy rods and hand preped forged rods are dependable to 11,000 and 4340 stuff is a breeze all depends on how the hole is done on the big end. its about pounds of force on the bottom end from the balancing job. Pay more for less then a 1 gram bal job, less pounds of force on the crank and mains,thats the key. It can go anywere from 400# to 8000# of force at 8000 rpms and youll never know why it blew or kicked a rod. I have a 6.900 rod in my bbc 454 china stuff preped and i spin it to 9500 plus , never broke a steel rod, alum yes. Your find but what did it get bal to.?/?? 4340 stuff is kick ass out of the box you guys dont know what your missing working on rods for aweek, but then you dont wanta.
my shit is within 2/10 of a gram,but i love my RPM,s crazy thats me.
 

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All depends on the motor balance job. Bal. is the key todays 4340 rods are kick ass as someone stated before pink chevy rods and hand preped forged rods are dependable to 11,000 and 4340 stuff is a breeze all depends on how the hole is done on the big end. its about pounds of force on the bottom end from the balancing job. Pay more for less then a 1 gram bal job, less pounds of force on the crank and mains,thats the key. It can go anywere from 400# to 8000# of force at 8000 rpms and youll never know why it blew or kicked a rod. I have a 6.900 rod in my bbc 454 china stuff preped and i spin it to 9500 plus , never broke a steel rod, alum yes. Your find but what did it get bal to.?/?? 4340 stuff is kick ass out of the box you guys dont know what your missing working on rods for aweek, but then you dont wanta.
my shit is within 2/10 of a gram,but i love my RPM,s crazy thats me.
I thought you want some amount of over balance for high rpm:smt102
 

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I've wondered about the over balance thing myself for sustained high rpm. Isn't a neutral balance job on a V8 actually running thru balanced and unbalanced conditions? I think I've read somewhere its balanced at 4000 and 8000 rpm? Or is this just another myth?
 
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