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rkuyers
04-19-2008, 12:25 PM
ive got a 427 tall deck never built one what do i have to do to make hp and rpms

jmtire
04-19-2008, 04:37 PM
bore it , and stroke it big!!!!

russ67chevelle
04-19-2008, 10:16 PM
i agree!!!itll take a big crank and should bore no prob to sixty over and more!!!!keep er shes a diamond in the rough

bbc476
04-20-2008, 03:16 AM
we run a 476 tall deck in our s/pro rail-8.32 @160 on pump gas,reliable as a rock. first check #2 cylinder wall next to the fuel pump boss,this normaly is the thinnest spot in the block,if it is over .140" block fill to the water pump holes and bore it .100" over,clearance the pan rails,deflash the block and throw arp studs at it,top and bottom.we run scat 4" crank,rods and srp 10.5:1 pistons,all forged,and brodix bb2 extra heads,de flash them ourself's.if you want to rev use at least 280/288 dur on the cam at .700+ lift,all roller,don't go cheap here,and springs with at least 260 seat/660 on the nose pressure.with a good intake and at least a 950cfm air flow;track tune,you will make around 700 hoss.we use msd 7al spark,42 degees early morning backing to 39 deg in the heat of the day. one last tip,all truck blocks have drilled oil gallery plugs behind the cam gear,this sqirts oil onto the cam chain using the lifter oil pressure.replace the right hand one with a solid 3/8 npt plug,you are losing pressure in that gallery anyway with the oil going around the distributer housing,the cam chain gets enough oil from the left hand jet and you won't be starving #2,4 valve gear on start up.If you want hear our motor go youtube.com/linda neal dragster,and turn up the volume !!

rkuyers
04-20-2008, 05:07 AM
thanx for the info one more thing to stroke it put a different stroked crank in or can i use car pistons and 6.375 rods we have most of the internal parts this is a low money deal its my 17 yr olds mud truck eng he built a 454 last yr blew it up piston rod broke in half took the crank & block you can see it at cardomain.com rotax_583 thanx again any info is apprecated

Bubstr
04-20-2008, 08:23 AM
Some of the things that won't transfer over are intake manifold and distributor. You will need a different one or spacers for the tall block.
I built my first one of these by mistake. lol It was a dummy block someone left in shop for a couple years. Did machine work before I found out it had a tall deck. Was the best mistake I ever made. The short comings are stock rods, even HD ones. I had good pistons for short deck so I chose to go with a 1/4 inch stroke and the long rod. 496. Mainly because these parts was off shelf items if I had to fix it fast. The heads are the limiting factor to high RPM, but they make great low RPM and for a budget racer, this is the ticket. Low RPM don't break as many parts. You will want at least a H/D oil pump also. There are a few of these that have a little more thickness in the cylinder wall. They where in 66 and 67 trucks or buses. They where a favorite of early fuel burners, before after market blocks. One of these school bus blocks was built, ran and qualified at the Indy 500 back in the day.

rkuyers
04-20-2008, 10:31 AM
thanx for the help i have 124 chamber heads 292 duration 560 lift cam 12:1 pistons for a short block all i need to find out is if i can use the crank in the 427 if not what do i need piston rods what lenth with what crank i know intake and dist. wont work with this combo what is a good intake and carb combo

topcat572
04-20-2008, 05:03 PM
I ran a few of these in the 80s,made a little over 700 hp with 454 crank and pistons, and a .400 long alum rod. One thing is not to believe Darts BS that the the tall deck intake will use a stock length distributor. Good luck. :D

Bubstr
04-22-2008, 12:04 PM
3869942 was the good 427 block but it came with 2 and 4 bolt mains. Weiand used to make a fair intake for these with oval as well as rectangle port

Either crank 454 or 427 will fit but you must use the flex plate or flywheel and harmonic balancer for that crank. 427 is internal balance and 454 is external. Here is the rub,you have a half inch of cylinder bore length to make up one way or another if you use 454 crank. On mine, I chose to get 1/4 inch from stroke and 1/4 inch from rods because I had big buck pistons and needed the up grade in the rods. you have several options. more stroke to 1/2 inch, lower pin position on pistons or longer rods. The combinations are abundant. For my purposes I found I had head gasket problems with the 1/2 inch stroke and rod breakage with stock rods. It was the logical choice. I don't think they made rods long enough at that time. You will have to get your calculator out to find a happy place for you.

russ67chevelle
05-01-2008, 05:41 PM
the tall deck 427 or 366 has deck height of 10.200" which is same as my 572 dart block.i run a 4.5 stroke crank and a 6.700" rod.my case in point is deck height length is the SAME