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I picked up a 427 tall deck as a project for my 61 half-ton. It's my understanding that this block uses the 4.25 bore of the 454 and the 3.76 stroke like a 396, but can be bored out to 4.5 to make a cast iron 540 cheaper than buying the performance blocks. Anyone have any experience with this long stroke motor or any advice? This should make for an interesting low RPM torque monster shouldn't it?

Lowboy

Sounds good, however remember a tall deck also has a wider intake. I seem to remember some drag racers using these back in the day. I thought they made spacers for the intake so you could use an aftermarket intake.. Good luck.

-R
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Lowboy,the cylinder wall thickness is what may limit the bore size.

Yes, the intake is specific. I don't know if there are any after market intakes for a tall deck. If I were you, I'd call Summit Racing and ask. The stock intake probably won't flow like a performance engine.

There are spacers available, made of all things, WOOD!

the heads on them are good flowing heads and yes the stroke is the same as any other big block except the 454. i just finished building one for my '74 Chevy C65 also they are really heavy

Hey Fleetside Lowboy, remember that the block is .4 inch taller to accomodate the 4th ring. Ask 47chevy where he got the pistons, they might be spendy.

47chevy6400
Can you find the casting number of the heads for me, or are the covers on. I wonder if the 366 heads are the same.
Bob

I saw this on a Hot Rod forum:

The spacers will make the intake fit,but will raise it up so high that the distributor wont work.You have 2 choices on how to fix that.One is to buy an aftermarket distributor with an adjustable collar,and the other is to mill the distributor boss down on you intake manifold to correct the differance.Bolt the intake down with the spacers and gaskets,but no end seals.Measure the distance between the top of the block and the bottom of the intake on the ends.Subtract about .060" and thats how much you need to take off the distributor boss.Good luck

More info here:
http://www.hotrodders.com/forum/427-tall-deck-information-book-129294.html


Also found this:

88961161
intake manifold, zz572/620 engine
• Aluminum single plane intake manifold is used on the
ZZ572/620 engine
• The carburetor flange is for a 4150-style carburetor
• Use intake gasket P/N 88962213
• For tall-deck blocks

the casting # is 330864 and i got stock armored 4 ring pistons from NAPA for about $60 each, but i only had to buy one because the crank broke and beat up the #8 piston other than that the engine was perfect but i rebuilt everything anyways.also does it still have the big truck bell housing and flywheel, if it does i would be interested in them.

427...Thats a LOT of Motor for a truck ...lol..hope ya can keep her pointed in the right direction! when that Tourqe Monster OPENS UP!...MAN IT WILL BE FUUUUUUUN!!!!!...im jelous!

The tall deck block can be bored approx. .080 depending on the wall thickness.Find some one with a ultrasonic tester and check max wall thickness.Use a 454 shaft and you have a 496cid.The pistons as someone said wil have to be special ordered from like Keith Black, Venolia,Arias ,etc.You will probobly pay in the range of $500 for the set.Becareful of the compression ring thickness , the perfomance pistons usually run a narrow race ring which will kill the longevity .Connecting rods you can run stock length 454 rods.The rotating assembly will require balancing as well.This is pretty old school concidering the different stroker options on the market for the stock deck height block.I don't think you will be able to achieve the 540cid.The one we built was for a mini rod tractor puller,roller cam,aluminum heads, and injected.Ran okay was about it.It did'nt like the blower it split the cylinders wide open.As for the intake you can probobly run the same one GM offers for the 572 cid this is a tall deck as well or spacers are an option.

Fleetside Lowboy
I am a big fan of stroker motors and have built a 496 for my 56 the advantage you have with the truck block building a stroker BB Chevy is the extra .4" deck height will allow you to use longer rods with strokes over 4.24 and IMO you should always use the longest rod possible.
The longer rods will help decrees piston side loading it also gives better dwell time that the piston spend at TDC and BDC witch will allow .5 to a full point higher compression ratio be used on the same fuel.
The longer the stroke not only increases the cubes of the motor too build more HP it is also like putting a cheater pipe on a wrench it gives a leverage advantage for more torque.
Here is a link to a thread on the Garage Insider where a guy was asking the same question. http://www.garageinsider.com/f/comments.php?DiscussionID=44&page=1#Item_5

61 suburban
A 454 crank and a .090 overbore will give you 474 CI a 4.25 inch stroked crank and a .060 overbore yields 496 but a 4.375 stroke and a .060 overbore would give you a 510ci motor now we are talking power.

I have one of these as well to put in my 56 1/2 ton. Please keep us updated on how it turns out. I found a dual plane Edelbrock intake at a swap meet in Dallas that was made for the tall-deck with out having to use spacers. As for you distibutor, buy the kind with the adjustable collar. You can get one from Jegs and Ebay. Best of luck to you!!!

Heavy Hauler,
Fleetside boy is looking for a budget motor though my displacment was incorrect and yes he can purchase a stroker crank for an added expense for more cubes.

Except for at the gas pump maybe...

Okay,if a guy builds a tallblock stroker,a 496 for instance,can it be used as a work truck motor? If I did build an engine like that,it'd have to be able to run on regular,idle for extended times occasionally on hot days and pull ridiculously heavy trailers for 500 mile stretches. would those things be possible,or would design restrictions make that impossible.
Speed

You can go bigger if you wish with a truck block due to the taller deck height. The 496 that I built is using a standard passenger car block as far as running on regular gas not a problem as long as you choose the compression ratio accordingly.
If you will be leaving any BB Chevy idle for any length of time at all it is a good idea to go with a roller cam, BB Chevy’s in industrial applications that idle a lot tend to flatten their cams. As far as pulling long distances the added torque will let you pull down in the RPM range making it an excellent choice for this type of work.

Cooling is important on big blocks. They make lots of heat and you don't want a stressed motor getting too hot on a long hard pull.