What consists of a "top end" and a "bottom end"?
03-07-2011, 10:49 PM
#1
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What consists of a "top end" and a "bottom end"? What are the components that go with each? I know the top has some pretty obvious components like heads, valvetrain, etc.
I always hear people saying talking about rebuilding top ends and bottom ends
Can anyone break it down for me? I'm still a newb trying to learn as much as I can.
Thanks.
I always hear people saying talking about rebuilding top ends and bottom ends
Can anyone break it down for me? I'm still a newb trying to learn as much as I can.
Thanks.
Seriously? You to have a combined almost 1500 posts and you're asking this.
03-07-2011, 11:10 PM
#4
Bottom end is normally crank, rods, and pistons. I would think that the oil pump and pan go into here, but not totally sure.
Top end is: Cam, lifters, pushrods, rockers, heads and intake.
Top end is: Cam, lifters, pushrods, rockers, heads and intake.
03-07-2011, 11:26 PM
#5
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03-08-2011, 12:11 AM
#6
the head gasket is the divider line... all above, top end aka valve train. all below bottom end, aka rotating assembly...youre not idiots, never said that... just called bs that they either didnt know, or didnt know how to use the forum considering how many posts they have. No harm meant...
edit.. also, cam is considered top end even though technically it is below the head gaskets i guess...
edit.. also, cam is considered top end even though technically it is below the head gaskets i guess...
I like it. 
03-08-2011, 12:32 AM
#10
03-08-2011, 02:03 AM
#12
Like everyone said head gasket is usually divider, and Like someone else said cam is considered top end, and I think this is because it controls the valves and amount of air. And on alot of cars the cam is actually located in the head (all DOHC or OHC engines are this way, an example would be any 32valve cobra).
So these are pretty basic terms and really generic as there are many different types of engines and the way they are put together
So these are pretty basic terms and really generic as there are many different types of engines and the way they are put together
03-08-2011, 07:47 PM
#14
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Thread Starter
the head gasket is the divider line... all above, top end aka valve train. all below bottom end, aka rotating assembly...youre not idiots, never said that... just called bs that they either didnt know, or didnt know how to use the forum considering how many posts they have. No harm meant...
edit.. also, cam is considered top end even though technically it is below the head gaskets i guess...
edit.. also, cam is considered top end even though technically it is below the head gaskets i guess...
I really didn't know this thats why I posted in the newb section,lol. Its all good buddy, thanks for the insight.
03-08-2011, 10:14 PM
#15
03-10-2011, 12:15 AM
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The head gasket thing is a nice quick way to divide it. Things like the cam, lifters, etc are somewhat sketchy but by definition, if they are located in the shortblock of the motor, I guess they are in the bottom end.
But consider cams in OHC cars; are they considered top end? It's the same part, performs the same function, but does an items location alone make it fit into the top or bottom end definition? Man if I had a bowl I'd be freaking out right now...
But consider cams in OHC cars; are they considered top end? It's the same part, performs the same function, but does an items location alone make it fit into the top or bottom end definition? Man if I had a bowl I'd be freaking out right now...
03-10-2011, 12:38 AM
#18
Ill buy that, it also rotates, so "rotating assembly" would cover it as well... its too damn late to contemplate this...
The head gasket thing is a nice quick way to divide it. Things like the cam, lifters, etc are somewhat sketchy but by definition, if they are located in the shortblock of the motor, I guess they are in the bottom end.
But consider cams in OHC cars; are they considered top end? It's the same part, performs the same function, but does an items location alone make it fit into the top or bottom end definition? Man if I had a bowl I'd be freaking out right now...
But consider cams in OHC cars; are they considered top end? It's the same part, performs the same function, but does an items location alone make it fit into the top or bottom end definition? Man if I had a bowl I'd be freaking out right now...
03-10-2011, 11:33 AM
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i consider the cam to be a "top-end" part even though it's physically located in the "bottom-end". it controls the parts of the top-end so i'd say it goes with them.
03-10-2011, 11:39 AM
#20
^ I did too but say you bought a short block SBC. Would it come with a cam? Ive never purchased one so I dont know. Im sure you could choose whether it came with one or not but is it generally included?
i just got this from Wiki.. not admissible in court but Id say its good enough...
From Wikipedia, the free encyclopedia
Short block is an automotive term describing an engine sub-assembly.
A short block is the portion of the engine block below the head gasket but above the oil pan. An in-block cam engine will also include the camshaft and timing gear. The overhead cam style of engine will not include the aforementioned parts on the shortblock. A shortblock is usually purchased to upgrade the water jacket, piston size or bore. Assemblies typically include the crankshaft installed and balanced along with the main bearing.
i just got this from Wiki.. not admissible in court but Id say its good enough...
From Wikipedia, the free encyclopedia
Short block is an automotive term describing an engine sub-assembly.
A short block is the portion of the engine block below the head gasket but above the oil pan. An in-block cam engine will also include the camshaft and timing gear. The overhead cam style of engine will not include the aforementioned parts on the shortblock. A shortblock is usually purchased to upgrade the water jacket, piston size or bore. Assemblies typically include the crankshaft installed and balanced along with the main bearing.