I've been researching engines for quite a while now, I am looking at replacing my poochy 350 and dropping some serious HP under the hood. This is not a project that will happen soon, but I am researching now so I don't squander my money on **** I don't need. I was thinking about getting a 540 c.i. but am not sure. I mentioned it to my father, who used to be a mechanic quite a while ago. He said my car is designed for a small block engine, and a larger engine will put strain on the car. He also said that big-blocks do not last as long as small-blocks. He had some friend a while back who had to replace his engine every 2 or 3 years. I know he knows his stuff, but this information is from 30-35 years ago, so I'm assuming today's BB engines are better built than that? The other thing I have to look at is price, for $500 more than the BB, I can get a 600 HP 383 and a 6-71 blower... either way I'd like to supercharge, but a $2500 difference would pay for my new rear end and axles... Anyone who is an "expert" in this are please give me some sound advice.

 

Look at Shafiroffs website..some awesome bang for the buck if you want a BBC. THere are great deals on large ci rat motors these days almost doesnt pay to do a ***** out sbc..yes you CAN make a sbc fast but if you want brute killer torque no replacement for ci.
GMPP has a 572 in 2 different versions that looks like fun. Lots out there, skys the limit depending on your wallet.

 

If someone had to replace any engine every 2-3 years then something wasn't built right or they didn't take very good care of it especially if it was a street engine. If a BBC doesn't last, GM wouldn't have put them in so many vehicles. Race engines are a little different as they're built for a lot of abuse and are taken to the edge of their limits.

No matter what engine you use, any high HP build requires a lot more than just the engine. The entire driveline needs to be beefed up to handle the extra power and the car itself needs a little help with such things such as subframe connectors, better suspension components etc.

Very few "cars" were designed for a BBC but that doesn't mean they can't be used. It's just a slightly heavier and bigger engine. The extra displacement is just a bonus. A 400 SBC has more displacement than a 396 BBC but the engines are not the same. Externally, the BBC looks the same from a 396 all the way to a 540 and a good aftermarket block can be bored out to make that 540 into a 555 or 565. An aluminum headed BBC weighs about the same as an iron head SBC so don't let the extra weight be a factor.

The trouble with a 572 is that it's a tall deck block which makes an engine swap a little more difficult. A high HP SBC is expensive. It's cheaper to build a mild BBC which puts out the same amount of power as a high HP SBC.

 

I plan on replacing the entire drivetrain, as a stock TH350 will not handle the HP of a BB. I plan on going with a Strange rear end that AlkyIROC recommended, as well as a custom axle. Not sure on the tranny yet, tho. The only one I found that looks like it would work costs around $5900...

 

I replaced my 350 with a 454 last summer, and have absolutely no regrets about doing it. The hardware to do the swap properly costs a bit more... headers, exhaust, cowl hood in some cases, etc... but the swap itself is fairly straightforward.

The 350 I had made good power, but the 454 that replaced it will make about the same HP, alot more torque, and will be alot more civilized as a street engine. I'd bet, dollar for dollar, it probably cost me less to build a 400hp 454 BBC than it did to build a 400hp 350 SBC, because you have to replace basically everything on the 350 to get there - heads, cam, intake, valvetrain, etc etc - the heads being the most expensive of the bunch by far. With my 454 I got a set of 781 (large oval port) heads on it, which will support more power completely stock and untouched than the 200cc heads I put on my 350 will, and they didn't cost me anything extra. The heads on the small block were not cheap. I'm using a TH350 behind my 454, but as stated, its a very mild 454, so I'm not too worried.

My opinion - go with the BBC, whether its a race car or street toy, you won't regret it. There isn't really any reason to spend a fortune building a 540 or 572 (which is a tall deck, which causes lots of problems by itself) for a street engine though, because you'll never get to really use it. I'd bet you would be more than happy with a healthy 454, or maybe build a stroker out of a 454 and turn it into a 496. Its a pretty common stroker and not all that expensive to build, especially compared to a 540+ which requires an aftermarket block. Its not hard to get ALOT of power out of a properly built, relatively mild 496ci with a set of properly prepped factory large oval (#781, 049) or mild aftermarket heads on it. You wouldn't need anything exotic for that, which saves money, time, and headaches.

If you wanted to just buy a new engine in a box though, I'd recommend a crate 502 from GMPP. Aluminum oval port heads and intake, 4-bolt block, forged bottom end, hydraulic roller cam, and 500hp right from the factory, warrantied, and a pretty good price too. Just needs a carb and headers, and a few other little peices. The 502 is the big bore block too, which could potentially be turned into something bigger like a 540 at some point if you wanted to.

 

Thanks to some advice on this thread, here's the engine I am looking at getting: http://www.shafiroff.com/pro/598_1065.asp It should have more power than the 540 I was looking at, even if I put a blower on it. I'm not sure a 540 with a blower will fit under my hood, even with a 6" cowl. The tranny I am looking at getting is this one: http://www.jegs.com/i/TCI/890/271600P/10002/-1 Is that something I need to get? I am looking for a cheaper/better suggestion, something that will hold up to the engine, but not more than I need...