zx1216

what is the max horsepower you can run with the stock crank without running into problems? I plan on building a motor with a cc 306 and possibly a 150 shot of n2o. Would the crank be able to take the shot of nitrous on top of a tuned 306 setup? I will be going with forged pistons and rods but i won't be able to drop 1k on a forged crank.

Red96Lt1

I think I've heard of someone running 600 HP but he changed it out cause he got scared

350 HRSS

I am curious about this as well. I am running a 306 w/ stage II heads, and it really spins high. And the torque is unreal.

I hope some others will chime in here

Mikey 97Z M6

RPM's will kill a crank before shear hp will. I don't think there is a definite answer to your question. As long as you're not twisting it past 6500, I think you should be fine. You could even limit your rpms while spraying to be on the safe side.

As an example, there are people making 550+rwhp with the stock crank on blower applications, but the rpms are usually not over 6k.

Mike

zx1216

good point with the rpms... I don't think you can say low rpm's in the same sentance as the cc 306 though. I prolly won't spin it higher than 6500 but you never know

zx1216

anyone else care to add anything? Also what pistons/rods do you recomend for my setup above?

FastZinTennessee

Anyone have prices on aftermarket cranks? Just curious.

Bad AZz Z28

well I had stock heads and a little smaller shot, but with a hotcam kit and the n20 it was good enough for the times in my sig and i didnt have any worries about the crank at that level (i assume 425rw range but I dont know). I could have tried more but the clutch didnt like it as much as the crank did.

I wouldnt worried about running a 150 with a cam, the pistons or even rods would probably go before the crank

you can get scat9000 cranks for like 200 and eagle forged ones for 450-550 though I would imagin, if you want alittle extra strength

shoebox

From Combination Motorsports for comparison:

EG-CLT3480 Eagle Cast LT1/SBC Crankshaft 3.48" Stroke $220.00

SC-9000375 Scat 9000 Series Cast Crankshaft 3.75" Stroke $220.00

EG-F375 Eagle Forged LT1/SBC Crankshaft 3.75" Stroke $599.97

EG-F3875 Eagle Forged LT1/SBC Crankshaft 3.875" Stroke $599.97

CA-LTDS375 Callies "Dragonslayer" Forged LT1/SBC Crankshaft 3.75" Stroke $759.00

CA-LTDS3875 Callies "Dragonslayer" Forged LT1/SBC Crankshaft 3.875" Stroke $759.00

CA-LTM375 Callies "Magnum" Forged LT1/SBC Crankshaft 3.75" Stroke $1449.97

CA-LTM3875 Callies "Magnum" Forged LT1/SBC Crankshaft 3.875" Stroke $1449.97

Mikey 97Z M6

Scat also offers a 4340 forged crank in stock and 3.75" strokes for the one piece seals. 599.00 through flatlander racing. http://www.flatlanderracing.com/



Mike

97SS0594

how high can you twist a cc306??

hvyss

When I still had my stock rotating assembly I shifted at 6400 and had a 7000 rpm rev limiter. I hit the limiter more times than I can count. I have read and been told on a 2 bolt main cast crank you are safe under 7000 rpms. But the problem of egg shaping bearings and excessive bearing wear over 6000 rpms does come into play. I ran my stock rotating assembly for 5 years, 2 years with NO2 and at 72,000 miles dropped a valve killing number 7 piston and bending the rod but no spun bearings. Lucky? Probably.
HVY SS

Nostang 96z

I run the times in the sig on 2 bolt mains and stock turned crank. I have no idea how much rwhp I make but would prob guess around 530-550rwhp. Would I feel safer with a forged crank?...yes but in the middle of my build things changed. Besides, there are lots of people making awesome power with the stock cranks. It is usually the other parts that let go before the crank does.

Matt