Mounts for 400 engine in a 84 grand prix

[Pitt]

My 84 grand prix had a V6 in it and I'm changing it to a 69 400. My question is I have 301 mounts for a 81 grand prix and the block holes aren't lining up with the motor mounts. Does the frame mounts have to be changed to? 🙁

 

[Intragration]

I am not a Pontiac guy, but I believe you're going to need 301 frame mounts. Also, the '69 block might have different mounting provisions than later 400s. How many mount holes are on each side of the block?

 

[Pitt]

theres 5 on each side and i'm not sure its a 69 block but thats what the guy told me.

 

[G-Body_Vet]

The frame mounts you need are Anchor #2387. You can get them locally or online pretty cheap. I know 301 mount brackets work in our cars, but I don't know if anything else will though. I've heard 301 TA ones will but I can't confirm since I've never done it. Worst case scenario, you can get mount kits from Butler http://www.jbp-pontiac.com/products/fas ... Mounts.htm

Big car mount brackets are too tall. I've been trying to find part numbers or a way of identifying which brackets are from what.

 

[Pitt]

I got the 2387# mounts .Those are the ones that won't line up to the bolt holes on the engine block.

 

[G-Body_Vet]

I got the 2387# mounts .Those are the ones that won't line up to the bolt holes on the engine block.

I don't know your level of mechanical aptitude so bear with me here since I don't know exactly what you're doing.

1. The old V6 mounts need to be removed from the frame.
2. The #2387 mounts need to bolt to the frame.
3. The clamshells bolt to the engine and sit down on the frame mounts

Maybe this will help.
http://pontiac-g-body.tripod.com/id48.htm

 

[tdvick]

It sounds like the block that you have is a '70 to '76. That should work fine for the swap. '69 and earlier would only have 2 mount holes and they wouldn't line up to the 301 block side mounts. If you want to find out for sure what year the block is, there's a date code back by the distributor hole. It will be 4 digits, a letter followed by 3 numbers, something like this E231. Also, as G Body Vet said, the mounts that you have bolt to the frame. You need to find a set of block side mount brackets from a 301 car. The pictures below show my frame mounts and the block side mounts that you will need to use.

I hope this helps,
Troy

 

[Pitt]

Thanks for the help 😀 Where can I get these side mount bracket ? Does anyone have any for sell or Know where I can get them? both sides.

 

[G-Body_Vet]

One of the members on here CGimbel usually has a stash. You might want to send him a PM.

 

[Pitt]

What is the most likly gear ratio for a 84 GP auto 7.5 rear end with a V6?