I am trying to determine if this is a standard or Tall deck BBC. I think its standard, but I have found conflicting info when I search online. Can someone tell me from these pics if this motor has a standard or tall deck?
Standard deck. See the water pump almost touching the head? Tall deck has way more area between water pump and deck surface.
I posted this last month, it shows a GM tall deck truck block on the right next to a standard block. Oh, and @Black Panther is correct.
If you can get a tape on it, from the top of the timing cover casting to the intake is about 1.5 inches on my BBC-standard deck
Looks like a standard short deck to me,first photo is a standard Mark lV, second photo is a Gen Vl, but both standard short decks.
Do not go by the pic of that Merlin Block,,,,it is misleading . The pic of the original post is of a standard deck block,,,,or at least it was . It looks like it has been decked some,,,by the way the pump is sitting . Tommy
Correct. That’s not a good comparison We have a 427 TD at work but it’s still in the truck. Not a very good reference.
Get the part number off of the intake manifold and check it. Those are regular, post 1987 aftermarket Edelbrock heads (with a California smog exemption number). If you put them on a tall deck block, you would need the correct manifold to make it work. If the manifold part number does not come back as a tall-deck one, you have your answer.
If it was a Tall deck its been cut down, By pick from Op its a standard short deck, by look of last pick "intake gap " 1 of 4 have been done ,intake cut,heads cut ,block cut, or much thicker Head gasket. but can be corrected with with a thicker intake gasket , or thiner head gasket, When using a stock BBC intake on a tall deck , spacers are required between head & intake , there was a factory 498 gm BB in a 1 pice main seal, can not remember if short or tall block .
If you're looking at an assembled, or partly assembled stock engine, look at the front of the intake manifold. If it's cast for dual thermostats it's a tall deck 366 or 427 medium duty truck engine. I believe they used 4 ring pistons as well.
^^^^ that only Applies to a stock motor that has not been changed. (Intake ) Dual thermostats identification. The easy way is to look at deck to upper water pump bolt holes. Stock Gm blocks. I have bored out 366 & 427 tall deck blocks , some 366 blocks will not take a big bore .
This stud is either bent, or they come out at an angle. If they come out at and angle, then this may not be the correct manifold for these heads. The manifold is pushed to the passenger side.
Take out any fasteners that remain on the heads that go through the intake. Remove any gasket junk. Set the manifold back down and get some pictures of how it fits. Let us know if that stud that is shown in the front is bent, or if it comes out of the head at that angle.
Ok, I did a deep dive. This is a Gen V 454, based on the shape of the casting features. Gen V and VI big blocks, at least, appear to have angled intake manifold bolts, although you cannot use studs (because physics). This would have started out life as a TBI equipped engine, which would explain the CA smog-legal heads. If you don't have a reason to buy those, like having to go to smog check, you can just buy better ones from Edelbrock, for much the same price. It also has a GM EFI-era temperature sensor sticking out of the front of the manifold. I cannot find any record that Edelbrock made a manifold to support the TD 366 truck engine.
looks like you'all have figured out that it's a later generation short deck block. Some guys look at the casting number on the back of the block, too. It might tell you something. But I'm assuming that you can touch the engine, and that it's not a picture from an ad that you're considering purchasing.
The reason that I say Gen V and not Gen VI is that if someone put those heads on a Gen VI engine, they made an expensive mistake. The ports on Gen V heads were about the diameter of a half-dollar. The Gen VI ports were much better. About the only thing that the Edelbrock heads shown would get you over Gen VI heads would be screw-in studs, guide plates, and stiffer springs. All of that would set you back about $2500 landed.
hmmm....looks like a gen VI 6 bolt timing cover, while the Gen V would have a 10 bolt. but I don't know much about the later models (after mark IV)
I'm pretty sure Gen V do not have mech fuel pump so that is another indicator of late model truck block.
The boss on the block remained for some time after carburetors were no longer a thing. It is still there on OTC blocks. This might be a block off plate.
Yep. That's why I specified "an assembled, or partly assembled stock engine" for someone looking at the potential purchase of an engine sitting on the shop floor or in the bed of somebody's pick-up. Especially when there's likely to be no proof available as to what the engine was originally installed in.
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