rpm range of a scatt 4340

i know this is beating a dead horse
but i am wondering what is a safe max rpm a 4340
scatt 4.150 crank can take
i dont have ti valves and i know that is also a factor
i normaly run my motor no more than 8000 rpms
but would 8500 be pushing it?
i have oliver rods good valve springs over sized crower lifters and shaft rockers
but i dont wanna take a chance on smokin my motor over 500 rpms

Jesse,
I would be more concerned with valve spring maintenance and tedious top end inspections more than the crank at 8000 RPM. If I ran that RPM, I would tend to inspect the valve train more often, including an accurate test of spring pressure. I think that a take-apart oil filter would be a great idea to keep an eye on the health of all other components. You can see if something is going wrong long before serious damage occurs by watching the type of particles trapped in the filter. If you have adequate valve to pistion clearance, I would take it up there, if you need to.
I know very little about truck pulling but is that RPM needed? I bet your engine makes good torque and power well below the 8 grand range. Depending on heads, cam and other factors, most of the 4.150s that I have dealt with make peak power at 6800-7100. Maybe it is a wheel RPM deal......for pulling...
Thanks,
Keith

jesse wrote:i know this is beating a dead horse
but i am wondering what is a safe max rpm a 4340
scatt 4.150 crank can take
i dont have ti valves and i know that is also a factor
i normaly run my motor no more than 8000 rpms
but would 8500 be pushing it?
i have oliver rods good valve springs over sized crower lifters and shaft rockers
but i dont wanna take a chance on smokin my motor over 500 rpms

The crankshaft would certainly not be your most prevalent problem.

most pullers i know run an aluminum rod for that kinda rpm.my neighbor runs a brand x in a prostock truck,470 cid,with a steel "gm"crank @8800-9000 rpm.the crank has been good but the valve train aint! head came off a ti valve last time out.......ass load of spring psi and old valves.

......ass load of spring psi and old valves. [/quote]

Recipe for disaster

Wheelie58 wrote:Jesse,
I would be more concerned with valve spring maintenance and tedious top end inspections more than the crank at 8000 RPM. If I ran that RPM, I would tend to inspect the valve train more often, including an accurate test of spring pressure. I think that a take-apart oil filter would be a great idea to keep an eye on the health of all other components. You can see if something is going wrong long before serious damage occurs by watching the type of particles trapped in the filter. If you have adequate valve to pistion clearance, I would take it up there, if you need to.
I know very little about truck pulling but is that RPM needed? I bet your engine makes good torque and power well below the 8 grand range. Depending on heads, cam and other factors, most of the 4.150s that I have dealt with make peak power at 6800-7100. Maybe it is a wheel RPM deal......for pulling...
Thanks,
Keith

Keith, I'm not a expert on truck pulling either,but what most of them are looking for is "wheel speed". That means 8K to 9K rpm's and the torque to keep it there. They love to sing those engines into the heavens. Lots of fun to watch and listen to.

i dont plan on running 8500 the whole time but for 3-5 sec's towards the end of the track
for that extra wheel speed
i do plant on going dry sump with a evac pump soon
i run a wet sump with a kasse pump for now
i am gonna keep it under 8300 for now but
if the crank will hold it and i keep this current set up for next yr
i wanna try to get 8500-9000
i will upgrade vale springs and vales if needed
i got good new springs and vales in it now
but i will need to swap in a differnt cam for 8500-9000 rpms
adney said he has seen thease scatt cranks hit that kida rpms with no issues
as long as the rest is set up for it
but it seems most guys that are running that kida rpm's are running crowers and bryant billits

The Scat Forgings are fine, its the quality of the machine work and and finishing that make the Bryant forgings more expensive.

Adney can finish a Crank anyway you want it, and the finer piece you want the more it costs.