6.300 rods in a 416 stroker

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Andy, If you don't mind telling.. Did the engine get dyno'd yet? If so, where did the power fall off? The 4" arms tend to drop around 6500 without a bit of effort and most peak at 6. I've thought this was due to piston rock and ring seal loss as rpms rise. A shorter piston I'd think would be worse whcih is why I'm curious.
 
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according to the paperwork you have a smaller then stock ( chevy) pin so the pistons will have to be fitted for a .927 pin

the rods journal ( big end) is 2.225.....i thought sbm was 2.25,... no?


FWIW - I have a 3.75" small block 4340 crank and 6.250 rods sitting around waiting to go in a stroker - you can use a longer rod, just not that long of a stroke IMO
 
The pistons in my 427 motor have a CH of 1.330 which is plenty tall. Lots of motors are built with pistons that are shorter than that and they do just fine. I'm running a 4.125 stroke crank, 6.200 long rods and a standard 9.600 deck. So 6.300 rods will work just fine with a 4.0 crank. As I said before, the length isn't a problem. The big end size might be a problem with a 4.0 crank. You might have issues clearing the oil pump pickup and/or the bottoms of the cylinders. I used the small journal Chevy rods and didn't have any clearance issues.

The 427 motor has been on the dyno and it runs just fine. It has a power curve like a Viper motor. 525 ft-lbs, 525 hp all in down low where we need it.
 
Now I am really confused on what I have, other than 8 beautiful looking paperweights. -- Calling ALL engine builders, please chime in??
 
You most likely have 6.300 long Chevy small block rods. Depending on who the mfg is those are probably very nice rods. They'll work fine with a 4.0 inch crank. You'll need a 1.300 CH piston which may or may not be a shelf item. You might need to clearance the bottom of the cylinder walls and you might have an issue with the oil pump pickup.

Double check the big ends to make sure if they are Chevy rods or Mopar rods. If they are Chevy rods then you'll need to order a crankshaft with the correct Chevy rod pins. The Chevy rods are better because the parts are less expensive and there are more choices for rod bearings. So there isn't anything wrong with the parts you have other than the fact that it seems to be causing you some confusion.
 
AndyF -- So your saying I'm not completely HOSED?? And I should be fine with working around these rods and for my 416 build? ...... Come on good news!!!!!
 
You can certainly use those rods in a 416 if you want to. Those rods may or may not be the most cost effective approach for a 416 motor but that is a different question.

Shady Dell Speed Shop is fairly close to you and Ryan there is a very sharp small block Mopar expert. Give him a call and see what he has to say. Maybe swing by and show him the parts you have and get a quote from him to build you an engine.
 
Thanks AndyF -- Ryan is about 3 hrs from me so he will most likely be involved at some point on this. I'm still in the early development stages of planning, but I definitely think an email to Ryan will help point me in the right direction during this parts gathering stages. That's for the info!
 
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