My 383 blew up a couple of weeks ago, so it's time for another rebuild. I have most of my parts together for my rebuild except for my cam...I'll have that pretty soon. Here's what I'm looking at...

Hone out to 0.040 to clean up the bores.
Hot tank block to get any junk out.
Probe SRS forged pistons, -12.8cc dish, 0.040 over.
Total Seal classic rings (came with the pistons).
Eagle SIR lightweight forged rods, 6.0", bushed.
Reuse crank (Scat 9000 cast, 3.75 stroke).
New main bearings, rod bearings, cam bearings.

Now, for the questions...

Do I need to rebalance the crank for the new pistons and rods? It was balanced before, but that was with stock rods and Speed Pro hypereutectic pistons. I'm unsure as to whether or not the rest of the rotating assembly affects the balancing in the crank.

Is there anything else I should have the machine shop do while it's in there other than what I listed above?

As far as compression goes, I'm looking at 11.19:1 static and 8.33:1 dynamic. I'm looking at the CC306 cam, so that's what the dynamic CR numbers are based off of. I've read that I need to keep the dynamic CR under 9:1 to run pump gas. I'm assuming I should be just fine with 8.33:1 dynamic CR...right? Could I safely run 89 octane instead of 93 octane at 8.33:1 (in a pinch, that is)?

Related to the above question...anything under 9:1 dynamic should run on 92 or 93 octane with no problems, right?

Would this setup be capable of handling a 100 or 150 shot of nitrous if I wanted to in the future?

Thanks in advance for any answers you can give me.

 

how'd you blow it up? or what happened?

 

I swapped out my old large cam (Crane 109841) for a much smaller cam (CC502) back in September. Now that I've learned about dynamic vs. static compression, I know why it popped.

I haven't torn the engine down yet, but I'm 99.999% sure that it ate a piston (and popped a hole in the head). It let go during a WOT tuning run (didn't go lean or anything, and timing looked fine)...we just heard a loud *bang!* and then *ting ting ting*, which was probably piston chunks dumping out of the exhaust. The car still starts and runs quietly, but it has antifreeze in the oil and puffs smoke at idle. The crank should be fine, which is why I'm planning on reusing it. I'm just replacing the rods and pistons for peace of mind.

 

Youre gonna find that you added quite a bit of weight rod and piston wise, definately get it rebalanced.

The octane question I am not qualified to answer

 

That's what I figured...just wanted to be 100% sure.

 

Jeff it blew up because.........YOUR 383 SUUUUUUUUCKS

 

I'm not sure either...that's why I was asking. It's not going to be an every weekend thing...probably a couple of times before I get bored with it. I just wanted to see if it was possible. I figure I'll hit my N/A wall at some point and I'll be pissed when I can't go any faster. If I can spray it a bit after that, I'll be good to go.