Thread: Big blk vs sm blk opinions..

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`64 chevy sb pickup, currently tired 305, wanting to build new engine, other attributes are turbo 350 with shift kit, 373 posi, would you go with mild built big block or small block, of course money is still an issue as with anything but I`m seeing big blocks on Craigslist for the same price as small blocks, anything in particular I`m looking for in a big block?

Big Blocks are strong, by design. For street use a four bolt main isn't even a gotta-do, lots of big blocks, Ford, Chebbie, Mopar, Caddilac, Buick, you name it running strong with just two bolt caps. I prefer a big block in a pickup, might want to tow with it some day so the torque is already there. Build the engine for torque in a street friendly rpm range and it will make you a happy trucker!!!!

Well I'm going with a BBC for the first time also. The repair parts will run more on a BBC than a Sbc. Guess I'll just have to behave HAHA

Pat may log in on this later, but the last BB I had had oval port heads. The intake manifold cost quite a bit more than one for the rectangular port versions.

Rich, I've had the 283,327,350,383,468,& now 496 chev engines....Liked them
all, but for a trk I would go with the BB, and with your toys, you could always
use it in one of the other.

It's true that the big blocks are popping up as reasonable as the small blocks. Pat McCarthy is our BB expert and I'm sure he will chime in with his usual expert advice and knowledge, re; BB Chevys.

As to the small block - they can be built pretty stout with 400+ horsepower being well within reach of an average builder and on a budget. TechInspector is the numbers wizard for cam/head combination and he will provide you with some real serious simulations if you ask nicely..

My opinion - small block bored thirty over with Vortec heads. Summit SUM-151124 are 67cc chambers and 170cc runners and are about $620 a pair - great base to build from.

The rest applies big or small block:

Get flat top pistons pistons that will give you 10:1 C/R. They can be cast (as opposed to forged) if budget is tight with a good set of rings. I've used KB, SpeedPro, FM (anybody remember Jahns) and NAPA "off the shelf generics" over the years and unless you're building a mondo-gorilla, they're all pretty much the same. I do like Sealed Power rings.

I like roller tip rockers. Roller tips track well on the stock valves and are not near as expensive as a full roller rocker yet significantly reduce the friction in the valve train.

Go with a roller cam and hydraulic lifters. Don't go crazy on the size. Sound is nice, but too much duration will give you a lumpy idle in gutless pig that is easily embarrassed by a Honda Civic. Use a true double row timing set - it's not the place to save a few bucks. Don't let anyone talk you into a "gear drive" - they are from the devil and are very noisy too!

Crank can be stock. Two or four bolt depending on what you can afford. Have your machine shop check and grind if necessary.

I really like the Edelbrock Performer RPM manifold and a 750/780 Q-Jet. I've done a ton of square bore (Edelbrocks) and I like them from a simplicity standpoint but really love the sound of the Q-jet secondaries coming to life. Summit (and others) make a new Q-Jet replacement that will perform well out of the box. The Edelbrocks tend to run rich and I find they need to be re-jetted often.

Use a stock HEI distributor with a new coil - GM is fine - they were fine on 350 Z-28 up to 454 monster factory motors!

Stamp your rod and main bearing caps prior to dis-assembly so you can return them to original places.

Be sure you take your block to a good machine shop and have it prepped:
- magnifluxed
- bored w/deck plates on
- cam bearings installed
- freeze plugs installed (brass is better than stock)
- oil galleys cleaned and new plugs (make sure to check on this - it can be a real bummer after engine is together [ask me how I know that!]
- rods checked and re-sized as required (note - I like ARP bolts, have machinist install them as well as your new pistons on the rods)
- line bore the crank journals
- have the shop braze your oil pump pick up to a new oil pump (stock pump is fine)

I'd buy Federal Mogul bearings from your machine shop - that way they can install the cam bearings and match your new crank and rod bearings if it needs to be turned.

Scrub-a-dub the block real well before you assemble. I use Dawn (get your own, not the wife's - believe me it's a few bucks well spent!!)

Dry the block real well and paint before starting any building. Use engine enamel and be patient for it to dry. Coat every bare surface with a light oil [DO NOT USE WD-40] after you paint.

I always use new ARP head bolts - a bit of money, but I think money well spent as then I know I've got good torque readings. I always chase all holes in the block with "blind tap" with a bit of Vaseline before threading in any bolts - you'd be surprised what can found in there even after a trip to the hot tank!

Get an engine stand if you don't have one. Harbor Freight has them reasonable. Get the four wheel. While a nit, I have always immediately replaced the wheels that come on an engine stand with the hard neoprene/rubber ones and use swivel type for all four. I like the drip (drop?) tray too as it helps to corral little pieces that tend to roll to the dark recesses of your garage when you drop them!

And trucks do need headers - just installed ceramic Hookers on my sons '71 Chevy - easy install, look great too!

Hope this helps - Let us know how you progress!

Regards,
Glenn

i know a guy that has a bbc 427 060 over with fresh machine work and a fresh 350 forged 030 new TRW flat tops. moly rings re cond rods ARP bolts fresh 10/10 crank hyd roller short blocked ,the427 bbc has many new parts new erson hyd roller cam . lifters. big valve heads.new trend push rods.new crane gold rockers . with forged . TRW pistons.male rings and forged GM std /std crank. new scat 7/16 I beam rods . both engines he will part with allways maged for cracks . allways held under 0003. on work . deck plates used along with BHJ tru deck and plateau honed. rods allways rebuilt with s ARP bolts both blocks have brass soft plug s and all plugs where they need to be

Thanks guys, I think you have swayed me, I`ve been on the fence on this for some time, my `37 runs a 406 sm blk now, 461 heads 202/160 stock bottom end just everything gone thru, 22 cc dished kb pistons, with sealed power rings, clevite bearings, cam is mild 450 lift 221 duration with 1.6 rockers, performer manifold, holley 670 dejetted 2 sizes, unilite dist, I know how this thing pulls, and I haven`t yet reached the end of the torque band on it, so I`ll build the same only bigger, one mistake I did make was the wife, yes she`s into this as well, she wanted a ( her version of it ) winer ...... gear drive in it, ok so to apease her I put in a sig erson fixed idler drive, lesser of the two eviels, well you can`t here the radio at 50 or above, so that won`t happen again. so far I guess what Im looking for is a 4 bolt but not to important, rectangular heads if I want to spend more money, but not really needed, any differance between pass high performance blocks vs standard....? and what if any advantage from a tall deck to standard deck block...? steel crank a plus...

there no dif from pass /hi per as they all have that casted in many .less a bow tie you do not needed a 4 bolt big block or rec port heads or 7/16 rods or steel crank good selling points to guys that think they need this stuff to go fast. any thing over 600 hp you may want some of it .built many bbc with 3/8 rods and two bolt mains. a tall deck 10.200 will let you put a 4.500 crank in a bbc with a longer rod in a GM 427 truck block . any thing like bow tie .dart .donovan. world .etc with a big bore 4.500 up to 4.625 with a 4.750 crank get you a 632/638 10.200 are abit more work to get to fit in some things

That works for me then......!