Does anybody know if there is a differance in horsepower between a Van Nuys
built Z28 versus a Norwood built Z28? Specificly in a 1978 Z28.

The assembly plant didn't control the engine type or horsepower. GM decided what each engine would be, and went through the Government control process to get them EPA approved for sale.
Both Van Nuys and Norwood got their engines from the same engine plants so they were identical.

It's not so much where they were built in '78 but rather where they were sold. Cars originally sold into CA were ~10HP less than 49 state cars (Emissions standards). True, the majority of cars sold in CA were built in Van Nuys but not all cars built in Van Nuys were sold in CA (think other Western states or even farther)where the CA emissions standards did not hold.

^Perfect answer!
My 78 was built in CA with 49 state EPA emissions equipment.
It was sold/shipped to a dealer in MN.

How can you tell the differance between one sold in CA with 175 Hp and the 49 state 185 Hp

You need to identify NA9 (California) emissions. Look at your build sheet if you have one. It will be on there. Also, the carbureter numbers are different for NA9 emission cars and 49 State emission cars.

What was different in the CA 78 Z's that gave them 10 less horses?

air pump?

You need to identify NA9 (California) emissions. Look at your build sheet if you have one. It will be on there. Also, the carbureter numbers are different for NA9 emission cars and 49 State emission cars.
No NA9 in '78...Emissions/High altitude RPO is NA6.

I'd assume that it would be on the emissions sticker on the radiator support.

I am looking at a 78 Z With 53,000 miles on it. #'s matching 350 4 speed. No t tops but has A/C. Has original spare with canister.
Needs little body work,frame and floor pans are solid. Need to replace complete interior with exception of door panels and instrument panel cluster.

Any idea what this car is worth?
Would like to do a ground up resto with my kids.

Thanks for your imput.
:bowtie:

No picture...just a rough estimate. About $3500 would be my guess...but without being able to see what kind of rust and other factors, (frame rails, under carriage, etc.) hard to tell. ;)

I am looking at a 78 Z With 53,000 miles on it. #'s matching 350 4 speed. No t tops but has A/C. Has original spare with canister.
Needs little body work,frame and floor pans are solid. Need to replace complete interior with exception of door panels and instrument panel cluster.

Any idea what this car is worth?
Would like to do a ground up resto with my kids.

Thanks for your imput.
:bowtie:

Can't estimate value but if it has MT then not a CA car originally...hope that helps