now sbc 400 possablities

[YOUNGBLOOD13]

Is what I believed. I have to reseal my mouse motor, timing seal pan and I am going to advance my cam 2°. Not sure if I am going to go aluminum heads on this engine. I have a 6" rod 355 that has a static compression of 175psi with a .047" gasket and .020 steel shim, I am going to put aluminum heads on that one and run it in my Chevelle. But all this has to wait till after the moving is done.

.047 gasket and .020 shim ? Why. You are killing quench with that much clearance. Shoot for .040 clearance. What is your static compression ratio? What size combustion chamber? The iron vs. aluminum is confusing to many. Assuming both heads are identical, the iron can make more power (by retaining heat), but if copression is too high, you will pop a piston or head gasket. You can't compare a modern aluminum to a 40 year old iron. Need more info: static compression, piston type, intended use and rpm, fuel type, transmission type, gearing, cam, carb or efi? It all needs to work together.

 

[Joel Wilson]

Yes, larger tires lower the rpm range for all transmission gears.
For me going from 33 to 35 will lower my cruise speed 125ish rpm.

Should change it a bit more than that, but I think it depends on which program you use to compute the final RPM.

If you are going to build the 400 and buy a new or reconditioned crank, I recommend having your con rods reconditioned as well, just to make sure they are true. Even if I bought new, I would do this. Cost me 80$ to have mine done and you can tell they weren't true before. I have yet to get this engine to ping and engine vibration is definitely less than before the rebuild. I also have cast iron heads.

I would think that you could do the 400 for under 5 grand. I have right close to that but everything is new or reconditioned except the block and pistons and I splurged and added some stuff. (Did I really need a +3 qt Moroso pan with crank scraper and windage tray?) Full roller cam would have put me at 5500 and next time around I will do that. My engine is not quite 4 years old so I know prices have gone up too.

I looked at the 383 engines and wasn''t impressed. The RPM range was no where near what I wanted and by the time I figured what it would cost to get it where I wanted, it was cheaper for me to build my 400 and I learned a lot along the way.