Do 400BB bolt up the same as 383, 440 to a transmission?

[javakmcharger68]

Guy was telling me today that he thought there was something different about the 400 block bolting to a transmission that came off of a 383 , 440. If I try to bolt a 400 to a 18 spline 4speed, will I have problems? Thanks

[Nacho-RT74]

I don't think so
BB and RB blocks are the same bolt up setup on all faces, only difference is raised heads/top of blocks

Even Hemis as far I know bolts the same, difference is for example flywheels. 8 Bolts instead 6 bolts on wedge engines. ( I can be wrong on this late one )

[javakmcharger68]

I always thought they were the same but I had to make sure, just to save myself trouble if I was wrong. Thanks for the reply

[694spdRT]

The only problem would be if your 400 had a cast crankshaft and it is externally balanced. The 383/440 were steel cranks and had intenally balancing so there could be an issue with the nuetral balanced flywheel. The crank may or may not have the pilot bushing drilled.

[Nacho-RT74]

isn't the opposite ? sorry I allways have crossed mind when we talk about which one is externally or internally balanced... I think the iron cast crank is the internally balanced

[71charger_fan]

When it comes to transmission mounting, a big block is a big block. Some of the cranks weren't drilled for pilot bushings if I recall correctly. So, if you're putting the 4-spd onto an engine that came from the factory with an automatic, there could be an issue.

Cast cranks are externally balanced and not all 383s had forged cranks. Mine was built with a cast crank and external balance.

[694spdRT]

It is my understanding that all big block 4 speed cars had steel cranks with nuetral balancing. I think the Six Packs with the factory heavy rods do have something unique though.

You could have a cast crank engine zero balanced during a rebuild or have the flywheel rebalanced I suppose.

[John_Kunkel]

isn't the opposite ? sorry I allways have crossed mind when we talk about which one is externally or internally balanced... I think the iron cast crank is the internally balanced

The counterweights on cast cranks are less dense than forged steel and therefore weigh less, so sometimes the cast counterweight isn't able to counterbalance the weight of the piston/rod without external weight being added.

[javakmcharger68]

Sounds to me, I'm in trouble. The 400 I have has a cast crank. so what has to be done for this to work. What would you tell a shop to do to a crank to make this transmission fit on that crank? Thanks

[Ghoste]

First, make sure that the back of the crank has been drilled out for a manual transmission pilot bushing.  Next, make sure your flywheel is for an externally balanced Mopar big block.

[Chryco Psycho]

fi the back of the crank is not drilled you have 2 options , you can shorten the front shaft on the trans by 1/2 or so , or you can drill a hole into the back of the crank for clearance & use the Dakota roller brg style pilot either way , I prefer the second approach
The flywheel has to be balanced to match the engine , if the engine is apart or being rebuilt I would switch to a readily available steel 383 crank & go back to internal balance , the Mopar performance engine manual has a template to balance a flywheel for a 400 as a second choice if the engine will not be apart

[javakmcharger68]

Chryco Psycho, what this about going to a 383 steel crank? I have one here, so this makes me curious. Thanks

[694spdRT]

You can use the steel 383 crank in your 400 block and then you will have an internal balanced engine. The 400 and 383 basically share the same internals so the crank is an easy swap. The steel crank should be drilled for the pilot bearing also. I would go that route if you are rebuilding your engine and putting in a 4 speed.

[javakmcharger68]

That was something I did not know.  O.K, so if I take the steel crank in to get a new pilot bearing spot drilled. What do I tell the shop to do? Size? How deep? What do I ask for when buying a pilot bearing? The reason I ask is every time I go out to do something to this car, nobody knows what I am talking about. Old chev is the language they know & use, dodge is not something that never ever seems to work. I trust what info I get off this site, because I have found it to be correct. Every time I go out to find out anything for the old dodge I get that far away look in the service guys eyes. Even the dodge dealer parts service guy doesn't have a clue, or does not care. Any help you can give me to explain this to another person would be great. Thanks

[694spdRT]

The pilot bearing hole might already be drilled in the steel crank which makes it perfect for what you are doing. I my case I just asked for a pilot bushing for my Charger at the local Carquest and they had it on the shelf. They are cheap so get a couple. If you are unsure just have the machine shop check and install it.

Chryco might know if the Dakota bearing works with the factory drilled steel crank if you want to go that route too.   

[Chryco Psycho]

the Dakota brg is the best route if the crank is not driilled ofr a pilot bushing , then all you need to dop is make sure the hole in therear of the crank is deep enough to clear the front input shafty on the trans , the hoile doesn`t have to be exact size or depth going with the Dakota brg 

[javakmcharger68]

When asking about the dakota bearing. What year? Any certain type of transmission I need to know about?

[chargerbr549]

One thing I might add is sometimes when you have a crankshaft that originally had an automatic behind it and there was a pilot bushing hole drilled in it, sometimes it wasn't final reamed to size unless a manual trans was going behind it, if the standard pilot bushing won't fit I know Napa sells the correct bushing with a slightly smaller o.d., if you need the part number I can get it for you.

[Chryco Psycho]

early 90s dakota , it has a roller brg in an alum puck & fits in the converter lip in the crank

[sixpack70]

That was something I did not know.  O.K, so if I take the steel crank in to get a new pilot bearing spot drilled. What do I tell the shop to do? Size? How deep? What do I ask for when buying a pilot bearing? The reason I ask is every time I go out to do something to this car, nobody knows what I am talking about. Old chev is the language they know & use, dodge is not something that never ever seems to work. I trust what info I get off this site, because I have found it to be correct. Every time I go out to find out anything for the old dodge I get that far away look in the service guys eyes. Even the dodge dealer parts service guy doesn't have a clue, or does not care. Any help you can give me to explain this to another person would be great. Thanks

Why does every darn place in existance have to only speak chevy crap! How boring! I guess it would make life too easy if a lot of people knew mopar, and then make it not as fun.

[Ghoste]

Can't completely fault them.  There are so many more Chev's that the shops need to know them because that's where the easy money is.  Not to mention they are broken more than the Dodge's.