For those motors, do you need a whole new motor, or can you bore the motor you already have, into a 355, 383 or 396?

Also, If you can bore the motor that is in your car right now, what are the estimated prices for each? Thanks.

 

All the motor sizes you listed are based on the 350 block, or at least can be. I believe that a standard 350 is a 4" bore, and a 396 is a 4.030 bore. So a 350 that is bored "30 over" is actually a 396...


I'm not 100% on this, but if what I have been hearing and reading lately is correct, then I am right.

 

These three displacements are based on the 350 block which has a 4" bore and 3.48" strock. The 355 is a 30 0ver 350 meaning it is bored to 4.03". Both the 383 and 396 have more stroke than 3.48" (3.75" for the 383 and 3.875" for the 396 which actually makes it a 395). Both the strokers will need new rotating asseblies (cranck, rod, pistons).

 

a 350 .030 ove ris a 355 and the 383 and 396 require alot longer thow so the pistion is moving farther up and down and it think they require longer thorw on the cranks. but a 355 is only a stock 350 with a .030 bore that i know.

 

You forgot stroke . To calculate displacement you need to know width AND length. Most bore their block out to 30 over to clean everything up. Then comes the stroke, longer stroke for more displacement. What displacement you want is dependant on how much money you want to spend, and what you're planning on doing with the engine.

You can go 396 or even bigger but you run into some extreme angles which can and will affect strength and durability to some extent and, more importantly, real clearancing problems that I would not want to tackle for a mere 31 cubes. If you were planning on just freshening up the engine with new parts and then giving it a severe beating with a power adder - n20 or FI then a 355 is hard to beat - it's practically indestructible with the right forged internals. The real power your engine will produce is not so dependant on cubes as it is on a killer valve train. 20 or 30 additional cubes will not make near as much difference as a killer set of heads with a cam to match. Invest your money in the right places

Dunn, you realize a stock z28 puts probably 250 hp to the ground and you can easily make 390 hp or more at the ground with just a new set of heads and a new cam. That upgrade alone will run 2 grand or more if done right. Now you can get away cheaper doing a home port job with a hotcam kit but you won't see such stellar numbers. When you start building the "bottom end" of the engine (rods and crank and pistons) you get into the big dog territory. 400 rear wheel hp will easily propel you into the 11's with halfway decent traction - you'll get kicked off the track for not having a roll cage and going that fast! People quickly forget just how fast an 11.7 et is and you can do that without a 383 or 396 etc.

Now if you're engine's blown and it's sitting in the garage right now on a stand.. well then.. it's a different story

Why don't you decide what you want the end result to be before you start thinking about how to get there.

Hope this clears some stuff up,