Thread: 427 tall deck what to do

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Okay what i'm looking for is simple answers nothing complicated. The engine is going to be used for street, no 1/4 or 1/8 mile runs maybe a few light to light incidents but that's it. rpm use probably won't go over 5500 okay maybe once or twice a year but only if pushed. I've worked on a few passenger BBC's so this truck engine is something new for me. I have read a lot of the threads here and it seems there's a thousand opinions and ways to handle this 427T. One thing i do not want to use is truck pistons i either wanna use regular 427 pistons or 454 pistons that could provide me a compression ratio of 8.3 to 9.3 no higher. I am going to use the large oval port open chamber 107cc aluminum heads that been collecting dust forever in the garage. So what i need to know is what crank and piston rod set up do i need so i can be able to use regular pistons. I have at the moment 3 forged 427 cranks in the garage i also have 2 sets of standard 6.135 forged h-beams. So if i gotta start trading stuff out or selling to get other cranks and piston rod lengths i don't think i'll have a problem.
In other words i'm looking to stroke the engine out but i'm searching for a set up that wont be much of a hassle not only to build but won't have internal rotating problems as far as clearence and have a smooth running feeling. I already have a camshaft which is a Hydraulic Roller Tappet at an advertised Duration 300/ 306, Lift .560/ .580 it is off one of my other BBC but i don't actually know if i can use it. I don't have a intake manifold but i will probably just get a regular performance dual plane one and get spacers for it and have the spacer holes grind to match the intake ports. Another question would be the distributor what to do with that. Headers no problem. The engine is going into a 50 Merc plenty of room in the cabin it has a 1972 camaro front clip welded to the chassis.

the tall deck is 10.200 a pass block is 9.800 so there .400 dif. so you want to use 454 pistons and a 454crank you need a 400 alonger rod that would be 6.535 same thing with the 9.800 427 if you use a 366to 427 crank and 427 9.800 deck pistons . or use a 427 piston with a 250 long rod with a 454 crank we had one spining with this set but the guy never built it up. i think we were in the hole abit 040 but that would let you use your rods and pistons . and get block deck to O deck or 010 in the hole it all piston CH were the wrist pin is in the piston so you can find that on JE /srp piston add you rod 1/2 your crank stoke will tell you want piston CH will work with rods and crank a 427 9.800 piston is 1.765 and a 454 piston is 1.645 that for stock rods. i have used intake spacers they work and you can get them in O port and rect port the dist msd make a slip collar or you can machine a dist and use a pully spacer of a collar or make one

So since the deck height is .400, i have to make up that difference. If i wanna use my 427 forge crank and be able to use regular 427 pistons then i have to get either 6.525 or 6.535 piston rods. of course depending on which ch pistons i get also 1.770 or 1.760. Is it safe to deck the block 010 in the hole? Cause i rather just deck it at 0 and just get the proper ch piston rod combo to get it at or slightly below were it should be at. Will i have any clearance problems with the rotation because of the longer rods? I wanna get a sound and durable base and just get my horses out of the heads and intake without going to wild on the camshaft. Thanks

I ran a 427 truck block in my pro stocker years ago---used 4.0 crank (stock GM 454 steel) a piston that was 454 compression ht and an alum rod that was .525 long

We ran 8.0 at 169+ mph---just couldn't get into 7 seconds or 170 mph
changed to bow tie block at 4.560 bore 4.0 crank (522 inches) was one of the first cars into sevens and over 170mph

Now a days you can buy manifolds for the tall decks and won't need spacer plates

Jerry

Originally Posted by LuckyBadAzzBoy

So since the deck height is .400, i have to make up that difference. If i wanna use my 427 forge crank and be able to use regular 427 pistons then i have to get either 6.525 or 6.535 piston rods. of course depending on which ch pistons i get also 1.770 or 1.760. Is it safe to deck the block 010 in the hole? Cause i rather just deck it at 0 and just get the proper ch piston rod combo to get it at or slightly below were it should be at. Will i have any clearance problems with the rotation because of the longer rods? I wanna get a sound and durable base and just get my horses out of the heads and intake without going to wild on the camshaft. Thanks

they do not make a shelf steel rod in 6.525 they make them in 6.535 jerry was running alum ? i would bet so yes you need to make up the short comming on the 9.800 .427 to the 427 tall deck that you need the 6.535 rod as for cutting the deck 010. i have cut over 050 off the deck it will not hurt the block but it did throw other things off then deck . even on a 10.200 every thing needs to be ajusted for the deck heigth . you will not get in any trouble using a long rod s you say you want to see horses out of just your heads not much cam or cr or cid and low rpm boy thats going to be a job .i would go for TQ and not HP and that can be done with more cid i be looking at a 454 .4000 crank 468 or a 4.250 that get to 496 and that will make alot of tq if the rigth year block i put a 4.500 crank in a 427 tall deck out to 525cid with not much work on oil pan rails and that made much TQ there is some tall deck intake but at the time i built the 525 i used spacers they did not make the air gap in a tall deck so you need to see what intake you want to run and see if they make it for a tall deck. when i built my first 572tall deck dart was the only one making one a that was a race intake not something you need on your build over 17 years ago there is more tall deck intake made like jerry said