The original engine in my 70 Monte Carlo was a 400sb and it didn't have close to the feeling of power that the mostly stock 396BB that is in the car now feels like. I like the torque of a BB and since you already have the 454, I would build that. Granted it would be more expensive to build, but it will be easier to get the kind of horsepower you want from the BB. I wouldn't go back to a SB in my car.

Wayne

 

i dont know if that 400 was the original motor in your car, but if it was like i said they were never built to be performance motors.stock hp was 165-265. as you can see the stock wildest 400 was still short 60hp of a tame 396. i cant say what year your 396 is, but i think if the 400 had decent factory heads and a cam similar to your 396 it would probably take the 396 out just on weight. the 400 has a slightly smaller stroke. .01 so torque would be similar and the bore on the 400 is bigger. i dont think its fair to judge a non performance motor against a performance motor based on displacement alone. you have to take into account head/cam technology has improved significantly since the last 400 was made in 1980. the original cam that was in my 400 if i recall correctly didnt break the .400 lift mark and the motor made absolutely no compression. if you look at cam,heads,intake,header prices i think you would see that a 400 would make less power, but not by a wide margin of a big block and cost quite a bit less. not to mention the monte is already a heavy car why weigh it down more with a bbc that will cost more to build. im a fan of bigger is better, but in this case i dont.

 

The 400 in my car was the original engine and in 1970, this engine was rated at 265hp and only came with a 2 barrel carb. My engine had been recently rebuilt when I bought it and had a cast iron four barrel intake with a quadrajet carb on it. It had okay power but nothing I would call real powerful.

The 396 that is currently in my car was not a performance version of this engine. It was a 265 hp 396 with a factory 2 barrel out of a 1969 Caprice. This was the only year that a 2 barrel 396 was offered and only in this body style. This engine was built for torque and actually has heads that say "truck" on them instead of "hi Perf" The factory cam is the same one that was put in the 325 hp version of this engine for the 69 model year. I still have the factory intake and carb off of this engine in my shed.

This engine was still in the 69 caprice when I got it and I drove it quite a few times before it was pulled to be freshend up to put in my Monte and it still felt more powerful than the 400 that originally came in my car. This car and engine only had 73,000 original miles on it when I got it and ran great.

So, I'm not comparing apples to oranges in this case. I don't know the engine torque specs for either engines but the 396 definately had more torque than the 400sb and felt more powerful.

I'm not saying small blocks can't be built to make serious power but it will always be easier to make hp and torque with a bigger engine. The only changes to stock on my 396 now, is its bored .060 over and has an edelbrock performer intake with a edelbrock quadrajet. The cam is a factory replacement and the heads are the original ones. Anyway, each to his own.

Wayne

 

my point about the heads were that bbc heads are all canted valves. its a better design. and the cam no matter what was going to be more aggressive than the 400s. it is apples to oranges. theyre completely different. of course a large engine will have to work less hard than a smaller one, but end of the day dollar for dollar the 400 would be a better choice than a equal sized bbc. ie 402/396. weight/price/hp/tq. i dont know the weight diff between bbc/sbc but id have to assume that its a couple hundred lbs. thats .2 in the quarter. price to build the bbc is going to be far more than a comparable sbc.

 

Like I said before, each to his own. I like BB's and that is what I run in my car. The 400 sb is not a very popular engine and many had overheating issues. A 350 would be a better choice to build given its popularity and the many aftermarket parts available. If the original poster is going with a small block, this is the engine I would recommend over the 400.

I agree its more expensive to build a BB and that is what I said in my original reply. It all depends on what your goal is.

The bottom line is I've had two pretty much stock small blocks in my car, the original 400 and the 350 I replaced it with. The 396 came after the 350 and with this BB in it, its a more fun car to drive. If I had wanted to, I could have built this engine up to be a lot more powerful than it is. If you like sb's, run them. I happen to like BB's.

I also have two 1998 chevy trucks, one a Regular cab long bed 1 ton with a 454 and the other is an extended cab short bed 1/2 ton with a 350. Both are 4x4's The 1 ton is completly stock and the only modification to the 1/2 ton is a Borla cat-back exhaust system. The 1 ton is a more powerful and fun truck to drive. Bottom line. Sure I could enhance the performance to the 350 and get the power to the 454 levels but if I do the same enhancements to the 454, its still going to be more powerful than the 350.

Anyway, its whatever the original poster feels is best for him and what he can afford. The best bang for his buck may be building up a SB but there is a reason BB's ruled in the Hp wars during the muscle car era.

Wayne

 

big blocks ruled in the muscle car era cause they had a ton of compression, canted valves, and out torqued the undersized small blocks of the day. not for nothing though all the radical small block cars could hold there own if not beat the big blocks on the street and the track against the big block counter part(ie w31 olds vs 442 w30,LS5 vette vs LT1,L79 vs ss396 chevelle). like i said a bigger motor wont have to work as hard as a smaller motor to make the same power. to my knowledge the op wasnt talking about stabbing a stock motor into his car, he was talking about building a motor for the car, so debating stock power levels of two different types of motors is as pointless as debating muscle car era motors, or stock motors in pickups. on your opinion that the 400 wasnt popular. thats preposterous, the 350 is more popular do to sheer numbers, and ease of finding one. the motor was produced for 44yrs and counting. the 400 was around for 10yrs, so of course it will be easier to find one. the 400 is extremely popular with racers, not to mention the crank is stuffed into the 350 all the time(383). hell if it wasnt popular,or sought after im sure world products wouldnt have gone out of there way to cast new 400 blocks. on the aftermarket part availability thing, i dont even know what you meant by that. why would it be difficult to find aftermarket parts for the 400? just about everything made for the small block chevy bolts to it, and any website you go to with sbc stuff will list it. just so you know im not bashing you or the big block at all. i just think that youre viewing things through a filter. i love big blocks. they make tons of torque and sound awesome, but theyre heavier and more expensive to build and theres no reason why a small block couldnt hold its own against one for less. on the 400 < 350 thing. i disagree, if hes looking for what the big block offers in a lighter, cheaper package the 400 is the way to go. overheating is easily remedied. the heads have to be drilled for the steam holes and have a good radiator and fan shroud. to the OP i would figure out your budget, realistic hp/ 1/4m goal, and work from there. personally i find the small block to be the better buy. unlimited budget id go big block though. good luck

 

If I had a 454 and a 400 sb in my garage, and they both needed to rebuilt, I would definately build the 454. It's a no brainer. You gotta have something bigger than the guy parked next to you at the car show, right? And that 454 emblem would be so cool on the side of the car. You will have more than enough power for that car whether it's a 327, 350, 400, 396, 454. But, the 454 is the KING. Yes your car will be front heavy. Your car will not do well if you plan to race it on tight, curvy, road courses and you will not be able to keep up with Honda Preludes on mountain roads. Every where else, your car will kick ***. If you can live with that, go with the 454.

 

sorry for the up coming rant. ive been to many a car show and the local one near me has tons of old guys with big blocks, and they are just that. a car for show. a majority are the same. factory headed, under cammed, over weight dog. you look at these big block car show guys and theyre the ones whos tachs are set at 4200rpm. cause they dont run it, it runs out of cam at 4500, or the car is all show. there are a handful of non assuming types that have something real going on. those are the guys you see that mean business. those are the guys i want to match up against. the guys with the tachs set at 7000, with the cheetah shifter, and the radials. they no its not about the size of your valve covers or how much chrome is under the hood. personally when i go to a carhop i park away from the crowd, keep the hood closed, and no badging. no one needs to see ,or know what the secret weapon is. when they hear a healthy small block thats bassy as hell with a real cam, they all turn and look, and they know not to take the car lightly. there are some serious bb cars at my show, but they are few and far between. im more afraid of the gbody or nova with the afr headed small block running a 10" radial and a slapper bar though. dont be influenced by opinion and what not. why not do a price total for both engine builds and pick whats best for you. remember it has to be a combo. so your heads, cam, intake, and convertor all have to work together. once you get it on paper you should rip a version of desktop dyno/dragstrip and put it in(i used to do this all the time for fantasy build ups. i thought it was fun. like high strung 327 vegas with a 6sp and a ton of gearing). i bet dollar for dollar the sbc makes more power per cubic inch and runs a better time. try and build both motors for under 3500 including machine work and i bet that small block slaps the big block around.

 

Good rant. Pretty much true. I'm a bit like you in that I just put my Camaro together how I wanted it -not for anyone elses taste. Mine is not pretty under the hood. mismatched parts, and no shine on anything under there (except my cheesy chrome air filter) So my hood is closed too. But, it goes like hell. Oh, and the tach is set at 6,300. Not bad. Not 7,000, but alot better than 4,200.

 

yeah if its worth anything my brother and everyone else gave me **** for building the 400 saying how there are a million crate motors making that kinda power for less money and less work. sometimes you dont want to listen to reason. if i had to do it again i would buy a crate 383 for it. theres a company on ebay thats actually reputable that builds crates for insanely cheap. if it makes you feel any better i dont spin mine 7g either but the cam doesnt stop making power till 7500. i shift around your rpm too. seriously though next time your at a carhop take a look at some of these old farts and there tachs, i know you can shift by feel/sound, but seriously 4000rpm its lame. theres one guy that goes to my local one and he doesnt really talk to anyone. 67 camaro 295 radials out back, bbc, tunnel ram through the hood, hood tach set in the 7s, and the back of the car says bring it. things so bassy it hurts your chest. you know his car is for real and hes clearly there to see whats hot on the street, and pick a street fight. im not one for backing down, but i know a faster car when i hear it and see it.