I am putting a 5.3 ls in my firebird and I was wondering if I buy a trans am hood if the measurements for the shaker will be the same as a 400. Thank you

 

That depends on the engine mounts and swap plates Get a CenterLine measurement from the shaker hood to the back Of the block where the transmission mates. Use that as a reference provided you are using the same transmission

 

Need more info. Are you going carb or FI?
FI makes it a bit tough. The LS intake bringing the air intake around to get to the shaker hood scoop is not easy. Some just mount the shaker to the bottom of the hood.
If you go carb you could get the engine and trans in and move it around as needed to make the shaker work.

 

I recently finished a 1980 firebird swap ( there's a thread on it, but need to finish uploading pics ).

I used one of the low rise aluminum fab intakes found on amazon that worked out nicely.

I am currently working on a 1976 Trans-am which had a 400 + shaker hood. I am also using a Fitech 70074 Intake. However, I am modifying the hood to bolt up the shaker directly to the hood, rather than have it attached to the motor.

Not sure if this answered your question on fitment.

 

not sure how to reply but I am using the th350

 

I am buying a intake for a carb. Not sure if where the carb bolts on is the same measurements as a 400

 

Could you rephrase the question ?

-You are installing a 5.3L
-you are considering changing the NON-shaker hood. to a 400 shaker hood.

Are you asking if the hoods are the same in terms of clearance for the motor ?

 

The other things to consider as you move the engine around to match the shaker scoop is header clearance. Oil pan to front cross member clearance. I would use adjustable motor mounts from some place like Dirty Dingo or ICT.
As far as I know shaker and non-shaker hoods are the same except for the hole in the shaker hood.
I won't worry about the T350. The cross member can be moved around easily.