I posted this in newbie a few days ago with no responses. I know you guys will know this one.
Picked up a '99 Vortec 350 out of a 1-ton Chevy. It was in front of an auto, and I am going to be running a manual tranny.
What bellhousing and flywheel do I need to look for?
Are the bellhousing bolt patterns different for the Vortec compared to the older 350's and other SBC's?
I think it has a 168 tooth flywheel. Are they the same as the older 350's? Internally balanced?
Also, was the stock flywheel 10.5" or 11"?
Anything else I am missing?
Thanks.

All 350s have the same bellhousing pattern. In fact, all 90* Chevy engines, to include V6s, Diesels, etc., until the LS1 based engines, all use the same bellhousing.

You need a flywheel for a one piece rear main seal 350, which started in 86.

They're externally balanced in the back and internal in front, but they only make one style of 1 piece rear main seal flywheel anyway, so none of that even matters. Get a flywheel that'll bolt up and you're all set.

The flywheel will be about 13" in diameter, 168-tooth. Fits a 12" clutch.

The bellhousing you need depends on the transmission. 88-91 "new body style" bellhousing for a SM465. 92-95 bellhousing for an NV4500 to use an external slave. 96-?? bellhousing for an NV4500 to use an internal slave.

Well, this is going to a T-18 tranny with a manual clutch (no hydraulics), so I assume it doesn't matter what bellhousing I use?
Also, I am assuming my 10.5" clutch disk will need to be changed for a larger unit to match the flywheel?
Thanks for the help guys.

All 350s have the same bellhousing pattern. In fact, all 90* Chevy engines, to include V6s, Diesels, etc., until the LS1 based engines, all use the same bellhousing.

You need a flywheel for a one piece rear main seal 350, which started in 86.

They're externally balanced in the back and internal in front, but they only make one style of 1 piece rear main seal flywheel anyway, so none of that even matters. Get a flywheel that'll bolt up and you're all set.


So are the bolt patterns different between the 1-piece and 2-piece rear main flywheels?
What do you mean by "They're externally balanced in the back and internal in front"?