A couple of Big Block questions....

[Snarf]

Lets say a guy is thinking of swaping from his 250 cid to a 402 cid. If that same guy were to get the proper BB engine stands, would he be able to bolt up to the manual trans bell housing without having to move it's location? He may wanna use the current three on the tree for now. Also, if all that lines up, what would he need to get the clutch z bar working with a BB? Also can a header be recommended to use with a manual transmission... thank you for any insight.

[RustyPile]

Originally Posted by Snarf

Lets say a guy is thinking of swaping from his 250 cid to a 402 cid. If that same guy were to get the proper BB engine stands, would he be able to bolt up to the manual trans bell housing without having to move it's location? He may wanna use the current three on the tree for now. Also, if all that lines up, what would he need to get the clutch z bar working with a BB? Also can a header be recommended to use with a manual transmission... thank you for any insight.

You didn't mention the year you're "thinking about", so what I have to say may not apply.. My '71 originally came from the factory with an I6 and TOTT.. It now has a 454 (same BBC as 402), and TH350 transmission.. You can use the I6 bell housing, but you have to change the engine mounts and frame brackets.. '67 -'71 use the same engine mounts. The '72s are different. A "clamshell" design is used. The frame and front crossmember are "pre-drilled" for these brackets. Trade the I6 clutch bell crank (Z-Bar) for a V8 unit.. All the other existing clutch linkage will work.

My truck has POL aftermarket frame brackets and engine mounts, and an aftermarket transmission cross member. The frame brackets for mounting the manual clutch bellhousing have been removed.

It goes unsaid that a much larger radiator and fan shroud is also needed.

[Mike C]

The big block transmission mounts are different from the small block and I6 mounts. To clear the firewall, the 396/402 was moved up and forward. So clutch rod through firewall is different as well. Raising the motor up results in floor clearance issues, thus the high hump floor for big blocks, and because its pushed forward as well, a longer driveshaft.

[Snarf]

The truck in question is a '69 C10. Mostly just trying to price out a BB swap vs. rebuilding the 250 between the fenders now. I actually don't mind the 250 and the 3 on the tree, but you know... big block...

[C101972]

Hi,
I have a pair of the’68- ‘71 Big Block motor mounts, they’re the frame mounts and the rubber motor mounts.
Let me know if you are interested.
Thanks Chuck