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I have been working on a 67" chevelle for some time now. I initially wanted to use the 350 small block that I built, but have decided that a 427 would be much more nastaligic. My problem is that I am ignorant about the 427. Are all 427's the same? or are there some differences? I have never built a Rat motor so I am doubly ignorant. Can you give me the best componants to install? And why? Also, what are the deferences between oval and rectangle port heads? thanks.
 

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i do not know much more than you on this subject but from working in a chevy dealership i replaced a few in trucks there are tall and short deck 427s the tall deck had a longer stroke (i think)that made it put out more3 torque but you will want to find a short deck for a car engine so it will wind up faster also it was hard to get parts for this engine but good luck on your project there is no replacement for diplacement when it comes to makin power
 

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BIG RAT!! ok enough for the funny stuff . There are differences in a 427 std block and a truck block . Here is the low down . the 366 and 427 truck block is about an inch taller between the timing cover and where the intake sits . the tall block allows for a 4th cylinder ring and a taller piston for heavy duty abuse . Now for the important stuff . The tall block can be used with a special intake thats wider to compensate for the differance in the blocks . but here is the trick . The 427 truck , 427 passenger , 366 truck and 396 and 402 all share the same crankshaft and rods . the 402 near the end of its production went to a junky cast crank but the other crank is a forged steel tuftrided bullit proof crank . The engines all share the same rods the primary differances are only bore sizes . What does this mean ,, truck engines are cheap but have a special heavier forged connecting rod that works perfectly in the 427 , 396 , 402 engines , the cranks as I said interchange as they are the same stroke and rod and main sizes . all the big blocks except the 454 and the new 502 are internally balanced so swapping rotating assemblies is easy . the truck engine has another goodie you can swap to your 427 or 396 402 engine the big beafy 4 bolt main caps that go front to rear and wedge the bottom end together . If you are having a hard time finding a 427 block heres another secret ,, the 454 is the basic same block with some hollowing out to allow for the extra stroke and weights on its crank so ,, find a bone yard 427 truck engine , yank the crank , rods and 4 bolt caps , get a 454 block , put the 4bolt caps on , have an align bore done , put the 427 crank and rods in with whatever oversize 427 piston it takes to fit your block and you have a fresh 427 ,, 454 and 427 share the same bore size ,, I have some experiance doing this with our race engines . My 396 has 4bolt 427 caps and the entire rotating assembly from a 427 truck engine . another thing to look for is the older model passenger car fat push rods , you need the guide plates of the old car or truck heads but the truck pushrods are too long so scrap them . I would use a set of comp cams roller tip rockers and a good set of manly valves with bronze inserts .. if you need any more help email me at [email protected] :eek:
 
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