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Discussion Starter #1
Hey so I have 1968 GTO that i am restoring and the old owner put a chevy 350 in her with the original TH350. What do you think he did to fit this motor?

I'm leaning towards motor mounts but not sure. also if it is motor mounts were these welded in back then or just bolt on adapters?

Please let me know your thoughts.

Thanks!
 

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To install a sbc into a GTO the frame mounts must be changed. You will need the Pontiac ones to re install a Pontiac engine. The good news is that it is only four bolts per side. The bad news is its a pain with the lower control arms installed.
 

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67 Basket Case Restorer
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You'll need a Pontiac transmission too. There's no practical way the PO mated the original trans to the Chev engine. There may be adapters out there, but I doubt he would spend the extra money for that when he could use a Chev trans.

Exhaust manifolds are different too along with the fuel lines and starter being on opposite sides of the frame. If the battery is in the original location, the cable must be 6-7 feet long as well as a fuel line to the Chev fuel pump. If everything was moved to the Chevelle configuration, then you have more work ahead of you.

The good news is that it's all bolt in and can be returned to original with the correct parts.
 

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Discussion Starter #4
You'll need a Pontiac transmission too. There's no practical way the PO mated the original trans to the Chev engine. There may be adapters out there, but I doubt he would spend the extra money for that when he could use a Chev trans.

Exhaust manifolds are different too along with the fuel lines and starter being on opposite sides of the frame. If the battery is in the original location, the cable must be 6-7 feet long as well as a fuel line to the Chev fuel pump. If everything was moved to the Chevelle configuration, then you have more work ahead of you.

The good news is that it's all bolt in and can be returned to original with the correct parts.

Nice! So the battery is on the passenger side currently and not the driver side like it is supposed to be. He definitely did exactly what you say above.

The trans is a TH350, that is my biggest issue I guess since it will need to be a Pontiac trans. I have looked at a lot of TH400 trans that are Pontiac but I am not sure which to get as they are all different lengths.

The original motor is in hand and will go back in once I finish stripping it down to the frame. The car has headers on the 350 now so that will go along with the exhaust (I was already planning this)

this being a 1968 GTO what and I would like to put a TH400 trans in her what trans would you go with? Short tail, long tail? I have no idea how to identify what normally would fit.

Thanks for all your help!
 

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67 Basket Case Restorer
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TH400 would be the correct trans and the short tail was in the A bodies. You will need a different driveshaft too, as the trans yoke is different between the TH350 and 400 and the length is shorter with the 400. Depending on the availability of used vintage parts in your area, these could be fairly common swap meet or craigslist parts. I would assume any used trans would need rebuilt unless it came with recent paperwork.

The trans will be the same across the Buick, Olds and Pontiac lines, so you have a broader base to search than just Pontiac. The driveshaft was the same also, including Chevelle.
 

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Discussion Starter #6
TH400 would be the correct trans and the short tail was in the A bodies. You will need a different driveshaft too, as the trans yoke is different between the TH350 and 400 and the length is shorter with the 400. Depending on the availability of used vintage parts in your area, these could be fairly common swap meet or craigslist parts. I would assume any used trans would need rebuilt unless it came with recent paperwork.

The trans will be the same across the Buick, Olds and Pontiac lines, so you have a broader base to search than just Pontiac. The driveshaft was the same also, including Chevelle.

Thank you!
 
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