I am going to build my bottom end sometime soon as i have bad rings now 137k miles on the bottom end. Want to be able to spray 250 to it IF needed (not all the time) and spray 150 - 200 to it all the time. Here are some combinations I have came up with so far.

Stock crank, SCAT H-Beam forged rods 5.7", SRP pistons, je rings, Callies 4 bolt maincaps

SCAT Forged 4340 crank w/ 3.750 stroke, SCAT H-Beam forged rods 6", JE pistons, je rings, Callies 4 bolt main caps
will do a 4.020 bore

reason I went with the 3.750 stroke on the second one is because If im buying a crank IMA get some more stroke to it and this would prolly help Torque down low N/A and make it more driveable w/ my cam.

Let me hear your opinions, on good or bad, also what do you think a ring type I should run, opions on the rod length? lemme hear it!
thanks!

 

1. JE pistons with "hardened nitrous series" rings seem like a good choice to me.

2. Rod length is pretty irrelevant for a motor at this level, but if you are buying new I'd say 6".

3. I like the 20 over vs. 30 over (or more) for added strength in the cylinder walls.

4. A 250hp nitrous shot will be pretty hard on the crank, I'd upgrade from the stocker.

Rich Krause

 

I spray 150-175 shots all the time on my stock bottom-end motor. If you plan on going up to 250, I like option #2 you have listed above.

 

Thanks for the replys
I have also heard that with a nitrous motor a too long of a rod would be bad? something about the piston pin will be too far up and not enough piston? someone care to explain? how about a 5.850" rod?
thanks
Brian