I'm starting to buile me a new motor here. I have a 4 bolt main 350, and a 2 bolt main 400. should I do a 355, 383(and what exactly is that, rod length, etc.) or a 406? I hope to later on add a supercharger and some nitrous oxide possibly so I was just wondering what would be the best for strength? thanks

Also I have going to use a 5140 or 4340 crank, 4340 rods and forged pistons no matter waht.

 

If it were "me" I'd do the 383, or 388 .060 over, since you have it use the 4 bolt mains especially since you plan on boosting it or using NOS... I LOVE MINE!

 

Stud the 2 bolt main 400 block and build a 406.

The simplest 383 is using the 350's block. Have the 400's crank machined down to fit into the 350 block. Use the 400's rods and the 350's pistons.

I ran that setup for 2 years running high 11's/low 12's. Everyone wants to use the longer 350's rods and special stroker piston but it's not required. I finally destroyed the engine when the "stock" bottom end and cast pistons let go after 200 passes and a lot of previous street mileage.

 

build it from the ground up with the plan of using an SC or NO2. Too manythings are different.. cam duration and lobeseparation angle for one..

 

Ya if you plan to run a s/c later on, you'll either have to use low compression now, or will have to rip into the block and rebuild the bottom end with deeper dish pistons. I had my block built, then i thought of going super, but the guy who built it said we'd have to replace the pistons to lower the CR, and then O-ring the block, as the gaskets might blow too easily. But i can run nitrous with no problems, up to a 150 direct port should be survivable. So either build up for a s/c, or forget running boost, build a high CR motor, and add nitrous.

 

since you're talking supercharger and n2o i'm moving this to the power adder board where it'll get trhe attention it deserves.

 

ya I am looking at doing BOTH sc and nitrous later on. the sc will come first, then maybe some nitrous at the track and stuff.

 

Whats the performance differnce when you run the shorter 400 rod instead of the 5.7 350 rod to make a 383?

 

I'm playing w/the idea. (350 crank in a 400 block)
It's got as good or better rod angle as a 350,
better bore/ stroke ratio and more cubes.
Seems like the best of both worlds to me. Apparently a lot of the circle track guys run
them and they really catch r's.

 

What kind of rods? I got to looking at 4340 forged cranks for 350 are alot cheaper than for 400 so I think I'll be sticking witha 350 crank. but that 377 sound cool.

 

The 350 block is tougher than the 400 block.

Base whatever you build around that.

 

About the rods, they make 377 kits for either length of 350 rod, but the pistons are custom (350 pin height, 400 bore). Here's a link to a kit with 6" rods:
http://www.pmeracing.com/triton/engc.../sbc-33770.htm

 

Buld the 383 and go with low compression if you definately plan on the supercharger. If you go with high compression and get a supercharger you will have to rip the whole motor apart again. Im making my final decision this week to build a crazy 383 motor and I plan on running 11s without the nitrous. Its always nice to pass an 11 with all motor and plus, superchargers can blow easily and there may be many tuning problems and maintenance with them. I had one but never seemed to get it going right. Build a 383 with 11.5:1 compression and get a shot of No2 for it. My future motor is dynoing at about 580 HP and 520 lbs TQ on desktop dyno.

 

I think I'm going to do 9.5 compression with supercharger at 12PSI and then drop it to 8 if I every run nitrous also.