427 tall deck

[BS_z28]

A friend of mine just but a 86 K20 that they put a 427 tall deck in it, but the engine needs an overhaul, overnight it will drip atleast 1/2 to a quart of oil out. should he look for a regular big block to rebuild, or start with this one. I what do you have to diffiferent on a tall deck?

[fmstruck]

Is it stock? Did they just stuff a truck engine in there, ie does it still have the intake manifold with dual thermostats, or did they put an aluminum manifold on with spacers, or did they spend the money for a tall deck aluminum manifold? Are you sure it's a tall deck?

[Hillbilly]

Tall decks have heavy 4 ring pistons. If he wants to spend the money it would be a great foundation for a 510. To rebuild stock? Go 454.

[BS_z28]

It is a true tall deck. it has an aluminum intake with a edelbrock four barrel, i am not sure if it has spacers or not. I think its a wiend intake. He just wants to build a reliable truck that he can drive every day. what would you recomend he does.

[Hillbilly]

It would be reliable rebuilt. Tell him to throw that carb in the ditch.

[fmstruck]

Hillbilly can correct me if I'm wrong, but If you wanted to use a 454 crank, I think you could go with a set of 6.535 rods and then use whatever 454 piston you wanted. You might look into a rotating assembly kit. If you use one with a Scat 9000 series crank, they're not terribly expensive.

[fmstruck]

It would be reliable rebuilt. Tell him to throw that carb in the ditch.

Amen.

[Lepa]

whatever, eddys are more "reliable" so for a daily keep it. For performance get a holley or spend moneys on a demon.

[Lepa]

Wait, i don't know anything I own a crappy dodge.

[c0z]

Why doesn't he just fix the problem that's causing that large of an oil leak? Why does it need to be overhauled?

[Lepa]

cause pulling the pan and fixing the front/rear main seal or the crankseal or umm... other things would be too easy?!?!?

[c0z]

true ^

[Lepa]

another vote thanks to jake aka fmstruck is the oil drain plug.

[fmstruck]

Yes, I would check that first before you overhaul it to fix an oil leak that you'll still have when you get done. Also, do a compression test and a leakdown test to see how bad it really is. If you're overhauling it cause it burns oil, it is a bbc, I have never seen one that does not use oil. If you are using an oil leak as an excuse to build a 540 then carry on. You have my support.

[Hillbilly]

cause pulling the pan and fixing the front/rear main seal or the crankseal or umm... other things would be too easy?!?!?

It also has NO compression and one of the worlds smallest camshafts fix that while its out.

[Hillbilly]

You can put a 454 crank in but then you are buying rods, you could get a 4.25 cast crank and do some juggling with stock rods and get there with stock pistons (think). That block will go .125 over. What is he really using this for? You don't put in a bbc in for a reliable truck that you want to just drive. Does he plan on pulling something? Lepa edelbrocks won't run even slightly off camber or up/down hill. The are show car carbs.

[fmstruck]

cause pulling the pan and fixing the front/rear main seal or the crankseal or umm... other things would be too easy?!?!?

It also has NO compression and one of the worlds smallest camshafts fix that while its out.

But why overhaul it, if it doesn't need it? Get it running decent, fix the leak, and drive it while you accumulate cash for a wicked tall deck build.

[fmstruck]

You can put a 454 crank in but then you are buying rods, you could get a 4.25 cast crank and do some juggling with stock rods and get there with stock pistons (think). That block will go .125 over. What is he really using this for? You don't put in a bbc in for a reliable truck that you want to just drive. Does he plan on pulling something? Lepa edelbrocks won't run even slightly off camber or up/down hill. The are show car carbs.

I think Russ and I tried to pencil this out and the whole rotating assembly has to be aftermarket in order to use a 4.25 crank. I don't think you can get there with stock stuff.

[fmstruck]

We tried so many combinations though, I don't rightly remember without looking at the books.

[Hillbilly]

We tried so many combinations though, I don't rightly remember without looking at the books.

I an not saying your wrong jake I just have to look at some compression heights for pistons.

[Hillbilly]

yep your right, you need a 1.94 tall piston 427s are only 1.78

[Lepa]

he never said if he was gonna go wheeling with the edeljunk lol.