427 tall deck

JMck64

Member
I recently found a 427 tall deck motor. Its a .030 bore with standard bearings on both mains and rod journals.
I found two ways of building this motor, stroker kit for a 496, or a 427 car motor.
I also have two pair of BBC heads, Rectangular port (3994026) open chamber with 2.19 int. 1.88 exh. and Oval port (3872702) closed chamber 2.06 int. 1.72 exh., but both are bare. Looking for the most economical builds for both, the 454 block is .030 over and if I purchase the stroker kit for the 496, I can use the internals from the 427 TD, and install 427 crank into the 454. Which would give me a 427 car block and a 496 stroker engine. I am looking for some ideas on these motors, any more info?
 
welcome to the forum
have a local machine shop carefully inspect the existing crank and rods ,
before you use them to build a 427 in a short deck/standard block
Id certainly have the rod bolts in the truck rods swapped for new ARP, rod bolts.
try to select a 6.385" connecting rod and 7/16" rod bolt rotating assembly,
for the 489 stroker

scat cast steel cranks tend to be better quality and more precisely machined,
than most other rotating assemblies from what I see.
given youll be using the two sets of existing heads you now have on two builds,
one a 489 stroker and a future 427,
the larger valve ,open chamber heads with a dual plane intake,
would certainly be my choice,
on a 489, stroker, the smaller oval ports are a better match to the 427 build,
obviously you'll need new pistons in the standard deck block and re-balancing the rotating assembly.
the oval ports may provide a bit more lower rpm torque, but the valves and closed chamber head design,
will be comparatively restrictive in the mid and upper rpms, be sure you select pistons ,
that get the static compression up in the 9:1-9.7:1 range if you use pump gas.

bore diam x bore diam. x stroke length x # cylinders x .7854= displacement

https://www.scatcrankshafts.com/rotating-assemblies/

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/

http://garage.grumpysperformance.co...he-bore-stroke-displacement.14906/#post-83901

http://garage.grumpysperformance.com/index.php?threads/scat-cranks-related-info.10930/#post-74729

http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

http://garage.grumpysperformance.com/index.php?threads/dynamic-vs-static-compression.727/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/
 
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a few related and useful threads,
for many people,
reading through the links and sub links,
will look like extra time and work that might best be ignored,
but it will eventually cost you time and cash,
if you don,t have the info the links contain.

the tall deck BBC is a very good place to start,
if your thinking of building a 489-496 stroker big block chevy,
performance engine
bbcstrokr.png

http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-55571

http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-3007

http://garage.grumpysperformance.com/index.php?threads/bits-of-427-bbc-build-related-info.15543/

http://garage.grumpysperformance.co...h-thinking-it-through-helps.15137/#post-86393

http://garage.grumpysperformance.com/index.php?threads/a-few-calculator-links.7108/#post-27382

http://garage.grumpysperformance.co...-potential-dream-bbc-combos.14607/#post-77976

http://garage.grumpysperformance.co...on-picking-a-shop-to-do-work.5053/#post-28837

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-52469

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/#post-15727

http://garage.grumpysperformance.co...ket-race-not-transportation.14229/#post-72588

http://garage.grumpysperformance.co...in-height-compression-height.5064/#post-66240

http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-51341

http://garage.grumpysperformance.co...onnecting-rod-rod-length-too-stroke-info.510/

http://garage.grumpysperformance.com/index.php?threads/maximizing-piston-to-bore-ring-seal.3897/

http://garage.grumpysperformance.co...ng-combustion-chambers.2630/page-5#post-82766

http://garage.grumpysperformance.com/index.php?threads/tall-deck-options.14678/#post-79151
 
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welcome to the forum
have a local machine shop carefully inspect the existing crank and rods ,
before you use them to build a 427 in a short deck/standard block
Id certainly have the rod bolts in the truck rods swapped for new ARP, rod bolts.
try to select a 6.385" connecting rod and 7/16" rod bolt rotating assembly,
for the 489 stroker

scat cast steel cranks tend to be better quality and more precisely machined,
than most other rotating assemblies from what I see.
given youll be using the two sets of existing heads you now have on two builds,
one a 489 stroker and a future 427,
the larger valve ,open chamber heads with a dual plane intake,
would certainly be my choice,
on a 489, stroker, the smaller oval ports are a better match to the 427 build,
obviously you'll need new pistons in the standard deck block and re-balancing the rotating assembly.
the oval ports may provide a bit more lower rpm torque, but the valves and closed chamber head design,
will be comparatively restrictive in the mid and upper rpms, be sure you select pistons ,
that get the static compression up in the 9:1-9.7:1 range if you use pump gas.

bore diam x bore diam. x stroke length x # cylinders x .7854= displacement

https://www.scatcrankshafts.com/rotating-assemblies/

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/

http://garage.grumpysperformance.co...he-bore-stroke-displacement.14906/#post-83901

http://garage.grumpysperformance.com/index.php?threads/scat-cranks-related-info.10930/#post-74729

http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

http://garage.grumpysperformance.com/index.php?threads/dynamic-vs-static-compression.727/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/
Thank you for the info. Last night I was plastic gauging the crankshaft, the bearings were STD. on both, but after the plastic gauge on the mains, 1).002 2).002 3).0015 4).0015 5).002 so I now need to have the crankshaft turned, I stopped there, so I am starting with .010 / .010 for the Mains and Journals, this engine also had the larger 427 pistons .030, brand new by the looks of it, so I will try to sell this 4 ring piston .030 for some cash. I will get the number to these pistons. But I will check your threads here tonight, again thank you
 
Last edited by a moderator:
I recently found a 427 tall deck motor. Its a .030 bore with standard bearings on both mains and rod journals.
I found two ways of building this motor, stroker kit for a 496, or a 427 car motor.
I also have two pair of BBC heads, Rectangular port (3994026) open chamber with 2.19 int. 1.88 exh. and Oval port (3872702) closed chamber 2.06 int. 1.72 exh., but both are bare. Looking for the most economical builds for both, the 454 block is .030 over and if I purchase the stroker kit for the 496, I can use the internals from the 427 TD, and install 427 crank into the 454. Which would give me a 427 car block and a 496 stroker engine. I am looking for some ideas on these motors, any more info?
Thank you so am I lol
 
Thank you for the info. Last night I was plastic gauging the crankshaft, the bearings were STD. on both, but after the plastic gauge on the mains, 1).002 2).002 3).0015 4).0015 5).002 so I now need to have the crankshaft turned, I stopped there, so I am starting with .010 / .010 for the Mains and Journals, this engine also had the larger 427 pistons .030, brand new by the looks of it, so I will try to sell this 4 ring piston .030 for some cash. I will get the number to these pistons. But I will check your threads here tonight, again thank you
Well I guess that late night post was off a bit, the crankshaft is within specs, the pistons that I have appear to be aluminum .030 427 tall deck truck pistons, any info here? What's a good cam for this motor is left stock or as is?
 
Well I guess that late night post was off a bit, the crankshaft is within specs, the pistons that I have appear to be aluminum .030 427 tall deck truck pistons, any info here? What's a good cam for this motor is left stock or as is?
Grumpy does not like the 4-ring pistons.
I have a 427 Tall Deck too put away.
Good shape. Blocks are not date coded on Tall Decks any year I have found.
Heads on it are Tall Deck 427 Oval ports.
Similar to the desirable 781's. 1984 casting date codes.

Cam was mild.
Only has 230 Hp most tall decks.
It may be more because in trucks they all had a Governor carb Holley 4bbl that limited cfm to only 300-400 cfm.

270 -280 advertised duration be a start.
Pistons stock are heavy.
But drop forged aluminum.
 
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Been about 1 year.
I was going to do the same just roll new bearings in. New oil pump.
New Cloyes True Roller Timing chain set.
Isky Mega Hydraulic 280 cam.
Tall Deck Moroso Intake spacers.
Modern Brodie race oval port intake.
Install into my 1987 Corvette convertible.
Backed by a TH400 trans fab my own trans Crossmember using drag tech fabrication.
I listened to Grumpy.
I will buzz it high.
6500 +.
Shelved project for now.
496 ci Stroker better. Proven so here .

Decided to put my Old 70 T/A back together in 2019.
 
It's a solid $5,000-$15k build project 496 depending upon power level.

Been told by other Chevy guys 454 better on a tight budget.
 
I just found out the parts for the 427 as in gaskets are not listed in parts stores, is it safe to assume that they different than 454 due to the 5/8 inch tallet and longer? And where's the best place to buy?
 
almost all the gaskets in a tall deck BBC interchange with a standard deck engine gaskets.
the intake manifold is wider the distributor needs to be the slip collar style to match the distributor intake to cam clearance correctly,
and if you choose to use the standard deck intake manifold youll need spacers on the tall deck.
https://www.summitracing.com/parts/msd-85561/overview/make/chevrolet
msd-85561.jpg

https://www.summitracing.com/parts/mor-65090/overview/make/chevrolet
mor-65090.jpg

 wnd-8206_xl.jpg

wnd-8206_xl.jpg

http://garage.grumpysperformance.com/index.php?threads/tall-deck-options.14678/

http://garage.grumpysperformance.com/index.php?threads/427-truck-tall-deck-engine-mods.14632/

http://garage.grumpysperformance.co...-the-oil-used-and-oil-level-does-mater.15592/


-65090_w.jpg
 
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With that in mind, using the Edelbrock performer dual plane manifold. What camshaft and lifter combo would you suggest? I'm using the closed chambered heads with smaller valves on the 427 TD, 1970 To 1973 peanut port heads. The range for performance is 1500 to 6500 rpm's, the heads appear to be stock, but I am looking to keep the lift down so I won't have to more machine work done. We have decided to keep the 427 TD as semi stock motor, and I will purchase a SCAT assembly for my 489 or 496 build.
 
flat tappet?
roller?
solid or hydraulic?
and whats your static compression.
what transmission,?
what cylinder heads will you use?
if automatic what stall converter?
truck/car rear gear ratio?
,and intended use?
do you have headers?
 
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Flat tappet- just more lift.
The pistons are the 427, 4 ring, but .030 flat tops, unsure of static compression, but the pistons are
Sealed Power L2377F30 Engine Piston
 
Forgot to add, 77 Chevy van with 2.73's right now and a turbo 350 trans. Looking to put a 700R4 trans.
Strange but that's my project for dad, he just went thru surgery and he lost his right leg.
 
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