# A couple questions about swapping my 1967 326/2 speed for 1970 400/400



## Crzybone (Apr 9, 2011)

A deal has come up that I don't think I should pass. A gentleman has a 1970 Catalina that he is selling. I can pick it up for dirt cheap. It has a strong running 400/400 2bbl (290 hp)combo in it. My 67 Lemans has a 326/2speed (250 hp) combo that leaves much to be desired. I figure that I'll pull the 400, renew the gaskets, put an intake and 4bbl on it for now (will eventually do heads and cam when $$$ builds back up) and, from what I've been reading, drop it in place of the 326. Is this a straight forward swap if I choose to go this route? Will everything work back? Trans lines, coolant lines, etc? I know right out the gate it's 40 more hp on paper, but the response of the 400 trans should be nice vs the 2 speed, right? And once I can replace the heads with a nice set of edelbrocks and a cam, all should be right in the universe, correct?

Any input at all would be appreciated. I'm not trying to build a land speed record breaker, just want a cool cruiser that will move from time to time. If I get positive feedback, I could pick up the car this Sunday. :willy:


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## FNG69 (Nov 15, 2009)

Engine would be the same, on tranny the 400 is longer than the power-guide. So would have to slide cross member back on frame and drill new holes. Then shorten the driveshaft or find a 400 one. If you was closer to Wichita we could check my extras and see if one would work.:cheers....Les

And once I can replace the heads with a nice set of edelbrocks and a cam, all should be right in the universe, correct? O-YES


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## geeteeohguy (Feb 2, 2008)

Huge upgrade, and mostly bolt-in. The TH400 in the big car is most likely a long tailshaft version of the trans, and can be used if you shorten the driveshaft. My choice would be to get the trans changed to a short tailshaft configuration. Even if you kept your 326 and bolted up a TH350 3 speed (direct fit), you'd think you've gained 100 horsepower.


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## facn8me (Jul 30, 2011)

Just did close to what your wanting. Ended up reusuing the turbo 350 trans instead of the 400 long shaft. New brackets are gonna have to be welded/bolted to the frame for the crossmember to have a place to sit. You will need a shorter driveshaft and a 400 yoke on the trans side. Not really expensive to do per say $150 for a driveshaft Fab up some brackets (I was gonna use some angle iron braced) and bolt it in.


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## FNG69 (Nov 15, 2009)

facn8me said:


> New brackets are gonna have to be welded/bolted to the frame for the crossmember to have a place to sit.


You had to do that cause of your convertible frame, I did too. Won't have to do that on the Hardtop or Post frames....Les


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## FNG69 (Nov 15, 2009)

Hey Crzybone hope you don't mine but I got to ask facn8me a quick question.

Facn8me are you going to be at the Tulsa Pontiac Nationals at Tulsa Raceway Park on April 28!!!!!!! Cause I do have it on my list this year!!... Les


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## facn8me (Jul 30, 2011)

FNG69 said:


> Hey Crzybone hope you don't mine but I got to ask facn8me a quick question.
> 
> Facn8me are you going to be at the Tulsa Pontiac Nationals at Tulsa Raceway Park on April 28!!!!!!! Cause I do have it on my list this year!!... Les


I'm gonna try.. mechanically it should be ready. Asteticallyy.. not so much. Even got a suprise in all this rain we've been having. I didn't glue the wood dash insert good enough and it's soaked up enough moisture it doesn't fit anymore. Hopefully it will dry out and I can do something about it but may end up having to start over. Past that I imagine a 389 tri power lemans will fit right in even if it's under construction. The power tour is coming close by too in june. 



And didn't realize the crossmembers bolted in differently on the converts. Should be a fairly simple inexpensive swap considering.


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## Crzybone (Apr 9, 2011)

Thank you all for the responses. I'm going tomorrow to look everything over, how can I tell if it's really a th400. I found a site that says the 400 has 2 dimples in the pan and the 350 does not, it that always correct? Any chance that the driveshaft from the Catalina would somehow be the right length for the Lemans?


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## facn8me (Jul 30, 2011)

400 looks like the state of texas. 350 rectangular with an angle on one corner


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## jetstang (Nov 5, 2008)

I also have a longshaft 400, known as a turbo 375 my tranny guy told me it uses a turbo 350 yoke, so you don't have to find a 400 yoke, which are hard to come by. I don't know if the pinion angle will be to great, but love to have someone else do it before I do.


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## FNG69 (Nov 15, 2009)

Crzybone said:


> Thank you all for the responses. I'm going tomorrow to look everything over, how can I tell if it's really a th400.




Uploaded with ImageShack.us

Can look for the 400 cast in it like this too. This is a 70 block. DR. side up at the front.Good Luck.. Les


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## FNG69 (Nov 15, 2009)

FNG69 said:


> Uploaded with ImageShack.us
> 
> Can look for the 400 cast in it like this too. This is a 70 block. DR. side up at the front.Good Luck.. Les


This is on the engine not tranny........Les


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## BearGFR (Aug 25, 2008)

As others have said, the engine swap is "plug and play'. Transmission will take a little more work, but worth it. Since you don't have a convertible alternate mounting holes for the crossmember may already be drilled in the frame. YOu're going to need drvieshaft work anyway, so whether you go with the short tailshaft on the TH400 or use the long one is up to you. I don't have firsthand knowledge of whether the long shaft trans will fit ok so I'll leave that up to folks who have experience with it.

Bear


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