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Discussion Starter · #1 ·
I know there are some old school guys on here that might can offer advice.

How high would you safely rev a stock crank and rod 454 with .030 forged pistons? :confused:

FOr anybody that isn't familiar with the specs of the 454. It has a 4.00" stroke with a 4.25" bore.
 
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Discussion Starter · #2 ·
5500 is pretty safe. You might want to freshen up the valve springs, but the bottom end will handle that no problem.
 
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Discussion Starter · #3 ·
Talk to the guys who race in S/A, S/B or SS/A, SS/B in the NHRA. I am sure that there are some 454s that are spinning up to 8000 rpm(or higher) with the stock crank and rods. Those guys are running 9s over 130 mph, so I am pretty sure they are going well past 6000 rpm. HTH

Steve
 
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Discussion Starter · #6 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by AdioSS:


How high would you safely rev a stock crank and rod 454 with .030 forged pistons? :confused:

<HR></BLOCKQUOTE>

Hey cheston... long time no see...


Theres quite a variety of "stock" cranks & rods...but generally the weakest stock internals in good condition will be plenty safe @ ~5500. If you happen to have someting that was from a performance application with a steel crank & rods w/ the 7/16 bolts etc that limit can be streched. My Chevelle used to have a LS6 short block for awhile & I shifted that thing around 6500 thousands of times.

Probably the most important factor at that point will be quality of assembly... when you start swinging something that heavy that fast, you will find out what short cuts were taken :D

Joe


Oh... BTW there was a "sighting" tonight of a certin silver something, albeit somewhat disappointing
( sorry... probably only Cheston will know what I mean :D )
 
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Discussion Starter · #7 ·
I haven't torn down the engine that I have so I'm not sure which rods and crank it is? One of the local guys is going to work on the crank a bit and if the rods are still in good condition, I'll reuse them. If they aren't, well, it would be a good thing to upgrade :D

I figured 6 grand would be no sweat, but the thought and extra power available for going a few hundred RPM more are inticing. :D It's all about power vs durability...

Randy, the heads will be worked on considerably and the springs will definitely be addressed.

Steve, the sound of a big block turning 8 thousand RPM would be awesome, but this is a "street car" and longevity is a bit of a concern.

Hans, I'm still wanting to know what your cam specs are


Heinz, I sent you an email ;)

Joe, I sent you a PM through the board.
 
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Discussion Starter · #8 ·
On one of my dad's stock bbc 454 we use to get it up to 7k on the juice. It sounds like a pro stock motor. One word awesome. The last time we rebuilt that motor was 15 years ago. Although that is also on a boat so the usage is way lower than a daily driver. But i drive the bbc hard all the time.
 
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Discussion Starter · #11 ·
I've got a friend who traps at over 7800 RPM with his juiced 509. You can, too, if you don't mind constant valvetrain maintenance, once-a-year lower-end rebuilds, and the occassional Big Meltdown.

With a 4" stroke, you'll hit 4000 FPS mean piston speed at 6000 RPM. Anything much higher than that for extended periods of time, and you risk shortening the life of the motor according to the usual rules of thumb (which can be bent or broken if you apply enough $$$). I'd go with a self-imposed redline of 6500 RPM or so, especially if you intend to use a hydraulic cam and want a fairly maintenance-free engine.
 
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Discussion Starter · #12 ·
I was thinking of going with a solid roller set-up, but hydaulic roller would definitely be easier in the long run.

(I'm a fan of CompCams)
If I go solid I would pick from Comp's Xtreme Energy Street Roller lobes on page 239, but if I go hyd. I'd go with Comp's High Lift Xtreme Marine on page 231 and their 887-16 lifters when they become available. Lift would be somewhere around .650 with 1.7 rockers, and I might go with some 1.75s to get the lift almost up to .700


At under 6500RPM, would I see much of a benefit going with the solids over hydraulic?

My guess is it'll probably be cheaper to go solid, plus the solid would net more torque which is a good thing for 2 tons cars.
 
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Discussion Starter · #13 ·
my dad has a 77 4wd chevy truck. spins to 7000 with no problem. stock crank/rods. 1971 454 block .060 over. some head work. sorry but i dont have the cam specs. 452 HP, 530 lbs. torque. it sounds real good turning up that high. it has a stock turbo 400 stall and the low-end power is good too.
 
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