I think a good well thought out 383 will fit the bill nicely down low, and if a quality hyd. roller mid 6k are reasonable. It's not really the "size" of the engine that limits the RPM potential, it's the valve train design, layout, weight and choice of components and the oil pan/crank throws to a point in the upper rpms'. Can you rev a Hyd Roller to 7k, yes you can, but choice of components are critical, and even then, it may not be for long. That's the dilemma, solid Flat-Roller for RPM, Hyd for under 6,500. I have a customer who was looking at some Crower Hippo's, $1,800 after taxes/exchange....budget is not a word that's used.
Im definitely leaning towards the 383 and the 400 the most. I saw an episode of Engine Masters where they had a Blueprint 400 run to 7000, so I know the potential is there down the road if I decide I’m not happy with it, I suppose. Some people say 383, and others say 400. I’ll keep looking into this.
I've built some nice 400's in the 570-590hp range, and from what I learned over the years, if going 400 based I like aftermarket blocks....and that right there does impact the budget right from the get-go. It's one of the main reasons of the price competitiveness and attraction to the 350 based 383. A good seasoned/spec'd and sonic checked 350 blocks are generally stable up to 540/550 range, after that, your best to invest in an aftermarket block.
X2 ^^ I fully agree with badazz on his statement. To a point, yes & maybe.....there's pro's and con's to both, depends what you want and where you want it..... Tearing down some long stoke engines with 20k's looked like they had 100K +, let's just say they did not "age" as well as there shorter stroke cousins....
Probably more to do with rod length, not so much stroke, but in this case the 383 and the 400 have the same stroke. You're only contending with bore size difference...
I’ve definitely read that if going with a 400, get an aftermarket block because of the rear main seal and lack of 2-bolt mains. Thank you, everyone!
I'm late to the party here, but want to add some detail. At this point in the game, building a 400 based engine is going to require an aftermarket block, not conducive to a budget build. Stay with a 4" bore based engine, a 383 small bock is capable of making more than enough power to scare you in a street car that sees occasional auto-X. Get something with a Hyd Roller cam for durability. Don't get hung up on 7000RPM, on the street and at an Auto-X you want a broad torque band that comes in early. Most Hyd Roller's will start doing odd stuff before you get to 6500RPM anyways. It blows the budget but I don't think you can beat the GM SP393 Deluxe for what you want to do https://sdparts.com/i-24502691-chevrolet-performance-19418657-sp383-deluxe-crate-engine-435hp.html
What's funny here is I went through the same dilemma. Some of the older folks might remember, but I scoured parts to build a 400. Got a block, Scat crank and rods with forged pistons etc..etc..I realized I would need some spectacular heads to compete with a BBC....I ended up selling all of it in pursuit of a 454. Bought a GEN V block from a member, found a factory forged crank and even got some killer Vic Jr heads. Sold all that stuff off because wanting to autox the car, weight in the nose was a concern. That's what started the path to the LS1...I think one way or another...this questions will come back around. It surely helped that when I bought my LS1, its was a brand new crate and only $2800