SBC 350 vs BBC 427

[Highsteel]

Been planning the rebuild for my '71 C/10 long fleet for a while. I finally confirmed that the truck did indeed have a 350 like the seller claimed. Its so anemic I was sure it was 305/307.

Casting numbers revealed 'high nickel' 350.

So the plan is/was something of a mid-range 383, like 9.0 - 1 comp, find some 2.02 heads, not too extreme of cam, RPM like intake with an Edel and a nice exhaust. Lookin for 325-350 HP. Is this close?

Now I have been given a '71 427 HP short block! I'm not completely sure if it is a tall deck truck motor or not. One place on the block says "truck", and another says "HP Truck and pass".

Now, I've never owned a big block vehicle. I've riden in some though. '69 chevelle 396, early 70's big mopar challengers, 'cuda's, and Road Runners.
Hang on!!

The question is, is the BB rebuild gonna take a WAY bigger bite of my wallet to build, and is it good motor to build if its a tall deck? I'm not real concerned about which engine I feed later on, but how much I have to spend to get there.

The 427 will cost more as all I have right now is the short block, need heads and intake and pan...., but would it make the same or more HP easier with not too much increase in price?

[joeys66pickup]

of course its gonna cost more But almost nothing you do to that 383 is gonna let it stand anywhere near that Big Blocks Shadow....big blocks are just a whole nother' Ballpark

[Alex1]

You will be much cooler with a big block. My stock 454 gets more attention than my buddy's 425hp 355.

[Highsteel]

Originally Posted by Alex1

You will be much cooler with a big block.

Deciding factor, right there! All else fails, measure it with the coolness micrometer.

[djracer]

its easy to tell if its a tall deck. If you look right above the water pump it is about even with the deck. If its a tall deck its about 3/8ths of an inch above the water pump bolt/gasket area.

[Super73]

In my opinion, A wild 383 will typically take down a mild to medium build big block (427ci). But if they are both built for more or less the same idle quality and drive characteristics, the big block should rain supreme.

I think doing a 383 with a set of iron vortecs and a 230ish* @ .050 cam would be very cost effective and probably shine over a stock headed big block. Patriot shows them on the web page with springs for $695. They are machined to acept non vortec intakes as well as vortec intakes.

Now if you can spend the money on heads for the big block, typically cubic inches>weight, it's just harder getting a heavier front end with more power to hook

I'm starting to sound like a Patriot employee, but I jumped on their webpage and they have big block heads as well. The least expensive ones are $1395 set up with .600 lift springs.

[djracer]

I lean towards small blocks for the street and big blocks for the track!

[kwhite4]

You guys are leaving out the small things ( which add to $$$ quick).
Motor mounts and the brackets
Water pump
Power steering brackets
Alt brackets
Flywheel
Exhaust
There is probably other stuff that will need swapping but these things I still remember from my change to a BBC.

Would I do it again YES........ nothing like a torque monster....

[Super73]

I always figures N20 to be a Small Block TQ equalizer Well, unless the bigblock has it too..

[UltraBlue71]

I have always heard that tall deck 427 truck motors are pretty doggy, a complete 180 degree opposite of the legendary short deck car motor. Dontknow how true it is though, Inever owned one. With that said, a guy can build a SBC a heck of alot cheaper than a BBC just look at your internal parts cost on a rebuild kit. I love bigblocks though, the neck snapping torque, stoplight to stoplight a BBC is tough to beat, but if ya gotta drive her everyday lookout, its gonna hurt!

[Highsteel]

Originally Posted by UltraBlue71

I have always heard that tall deck 427 truck motors are pretty doggy, a complete 180 degree opposite of the legendary short deck car motor. Dontknow how true it is though, Inever owned one. With that said, a guy can build a SBC a heck of alot cheaper than a BBC just look at your internal parts cost on a rebuild kit. I love bigblocks though, the neck snapping torque, stoplight to stoplight a BBC is tough to beat, but if ya gotta drive her everyday lookout, its gonna hurt!

It may be true that a truck motor, in its stock form, may be a little doggie compared to one from a Chevelle or whatever. However, it is my understanding that that very same 'tall deck' is more accommodating to the various changes of the rotating mass of internals.
I don't recall for sure what the plan was, I thought the man building it said something about a 4 1/2 inch crank and CI of around 520. I am completely cluless when it comes to BBC configurations.
I do know I run across all kinds of small blocks constantly. I just found a low miles 10:1 '010' .030 over 350 short block for $150 and $75 for the tbi heads! The prices I'm looking at for just the heads for the 427 scares me. I can put together an ample small block for the price of heads and a crank for the other.
But, when all the hype and shop talk dies out, its my truck. And if my best friend wants put a stroked to the moon, who knows how many cubic inch, torque building, neck snapping, tire melting, Chevy Big Block Monster Motor in my truck, I just might have to let him.
Who am I to deny him this obvious pleasure?

[UltraBlue71]

I have heard it said you can build 2 sbc's for the price of one bbc, the 383 for example, hillbilly big block (haha) is a great way to make some low end grunt for lower bucks, right now I can get a bone stock 396 from my buddy really reasonable (we never have discussed price) and get it set up like a 402 like was in our year/model trucks to begin with or I can rebuild my good ole 350 with a 400 crank and some machine work and a decent set of heads and make some great horsepower. Like you said friend its your ride, BBC's are cooler than snowman poop, but I am a family man too (4kids) on a budget, bottom like is if you can afford it, do it, but the mileage is gonna suck, if you dont drive it all the time, like me, it probaby wont matter much but driving a BBC daily when gas is high, sucks!

[383Ram]

Originally Posted by UltraBlue71

I love bigblocks though, the neck snapping torque, stoplight to stoplight a BBC is tough to beat, but if ya gotta drive her everyday lookout, its gonna hurt!

This is what is keeping me from building a BBC. My 383 i am building will (in my plan anyway) will get some decent milage, run on mid grade gas, could be run daily, and hopefully make a bunch of torque. And with aluminum heads, it'll be light. But yea, the big block itch is there and i am trying to fight it as i keep running across big block deals.

[Marv D]

There is a point (and I honestly don't know where that is these days) that a BBC is cheaper to build than a SBC. A stock 396 or 427 will make more torque in STOCK form because of the heads. Plain and simple the internal combustion motor is nothing but a big air pump. The more air you get IN and OUT, efficiently, the more power your going to make. The BBC heads are going to win hands down there every time. BUT.... if it takes $3500 or $4500 to totally refurbish a 427 BBC, you can build a decent 383 with a good head flowing in the 250-260+cfm range and make as much or more torque as the stock BBC. When I say 'totally refurbish' I'm not talking about a ring job and touch up the valves/seats. I mean replace the guides, probably new seats, some new valves....bore, new pistons, turn / tuen the crank, new cam/lifters, new rockers to replace the worn out stock slippers.... when you add it all up it get's pretty pricey. Sometimes for the same price you can buld a stroker SBC, hypereutectic pistons, cast crank, decent aftermarket rods, put a set of $1500 heads, $500 valvetrain on it and make a buttload more power than the stock BBC. Like mentioned, once you start finding / purchasing barcketry to switch from a SBC to a BBC,, you better add PLENTY to that budget. Oil pan, headers, everything you don't have adds to the cost. And that line,,,, that line where a more 'built' SBC is cheaper than a BBC gets more appealing all the time. Also,, there is that line there that once crossed, the SBC just doesn't make sense any more.

That's STRICTLY from a power standpoint and doesn't even attempt to address the 'street drivability' issue. And were not going to address the COOL FACTOR of spanking the socks off those 'attention whoring' BBC with our little sbc's now are we

[AKoldstyle]

I gotta say strictley from a cubic inch vs hp stand point that, every inch counts and the weight diffrence between the sb and bb is no more than 200 pounds in stock cast iron weight. I have built many diffrent combos of sbc from 327-408 and found the same principals of engine building hold true for the 3 bbc engine I have built. I think if it where me I would punch that tall deck out however punch it takes to clean up and buy a complete 4.25 storker kit. You are now in the 500 inch range and should be more than enough grunt to move you.

Best of luck on which ever way you go!

[joeys66pickup]

what would all you say on a 396(402) versus a 406(400+.30)? both done whatever you want to make em Solid!! i think the 396 would overtake because of the stroking factor of making it a 427ci