400 Pontiac & 350 trans in '71 Chevelle

[tree_fiddy]

Hello everyone. I am thinking of doing this swap and have some questions. After reading a few threads on this forum and a couple elsewhere, I'm still unclear on some details of this swap.

Here is what I know I need so far.

frame mounts from a GTO/LeMans/Tempest
accessory brackets and pulleys
extend the fuel line that runs to the fuel pump
move the transmission cross member back for the Pontiac trans
run a new cable for the starter from the battery

Now for the questions.
Are the frame mounts the same for all size V8's?

If I use the Pontiac trans, is there any other mods to the cross member other than moving it back? I've seen the adapter to bolt my TH350 to the Pontiac motor.

Can I hook up my shifter linkage to the Pontiac trans?

Will I be able to use my stock drive shaft?

Will I need to get a new kick down cable for the Pontiac 350 trans? (I'm not sure if Pontiac called their 350 trans a TH350)

Will I need to get a different speedo cable?

Can I use my Chevy radiator, or will I have to use one from a Pontiac A-body?

Will it be easier to run manifolds instead of headers?

Will headers for the Pontiac motor fit on the Chevelle?(seems like a dumb ?, :noidea: )

I know I'm forgetting things. I'm about to go cross eyed from searching this forum, reading, and typing. If you guys know something I left out, please post up. I would appreciate any and all help. Thanks in advance.

[engineer]

Now for the questions.
Are the frame mounts the same for all size V8s?
-frame mounts for pontiacs differ by year of engine, so what year Pontiac 400 are you using?

If I use the Pontiac trans, is there any other mods to the cross member other than moving it back? I've seen the adapter to bolt my TH350 to the Pontiac motor.
-use pont. TH350, chevy crossmember will be fine. no need to adapt chevy trans to Pont. 400

Can I hook up my shifter linkage to the Pontiac trans?
-yes, use chevy trans linkage bracket on pontiac trans shaft.

Will I be able to use my stock drive shaft?
-yes, pont. TH 350 should be in the same position on the frame.

Will I need to get a new kick down cable for the Pontiac 350 trans? (I'm not sure if Pontiac called their 350 trans a TH350)
- kick down cable is the same
Will I need to get a different speedo cable?
- no.


Can I use my Chevy radiator, or will I have to use one from a Pontiac A-body?
- use BB chevy radiator or SBC one from AC car. BB is better.

Will it be easier to run manifolds instead of headers?
-you could use either.

Will headers for the Pontiac motor fit on the Chevelle?
- if you mean will pontiac headers clear a chevelle frame yes. pontiac headers on a chevy motor or vice versa, no.

now battery needs to be switched sides along with fuel line, chey Ps pump must use pontiac brackets, chevy AC compresssor and lines must be switched, as well as alternator.

[474injun]

you wont have to move the crossmember if you are using a pontiac motor and tranny your fuel line should be fine, your radiator should be fine, your linkage will bolt up, and the only other thing that may need messed with is moving your starter cables to the other side of the motor, Oldsmobiles and Pontiacs have the starter on the driver side, Buicks and Chevy on the passenger side, all applicable headers and hoses will be purchased for a 68-72 Pontiac A body. hope this helps.

[tree_fiddy]

Thanks for the replies you two.

-frame mounts for pontiacs differ by year of engine, so what year Pontiac 400 are you using?

I'm not sure on the year. I will find this out and post back up.

- if you mean will pontiac headers clear a chevelle frame yes.

Sorry about that. I did mean if I put the Pontiac motor/trans in the Chevelle, will the GTO/LeMans headers clear the frame and fit properly? You two answered that though.

Thanks again for the replies.