[Jons69chevy]

I have a 69 air conditioned car that was originally a small block car and I am making the switch to a BBC. I am trying to leave air conditioning in the car but I dont have the outer ac box. BBC ac boxes are hard to come by so my question is this: will a bbc fit with a sbc ac box? what are the differences and what are the issues other than the obvious-not looking original? What are my options? Thanks....Jon

[bcvet]

air box out of 74/75 olds or pont, chevy. Change the whole system, big block will fit.
Now you will have more room than with a stock box for a bb.This system will change to 134a very easy. No p.o.p. valve

[TJS69]

The angle of the box from the firewall is different between a small block car and a big block.
The small block angle is about 45° and a big block is about 60°.



Thanks Click, Your picture ! Your Car !

[Jons69chevy]

another question for each of you. 1. any particular model of olds/pontiac? do I need to change the inside box and outer?

2. with the difference in angles from the firewall, will a big block fit with a small block box?

Please bear with me, I dont deal with ac very often and I havent ever paid too much attention to air cars at the car show.

[TJS69]

1) I would look at Nova's, Omega's, Ventura's, Apollo's .
.....You will need both the inner and outer boxes in the engine compartment.
2) I don't think so, as a big blocks frame mounts move the engine about an inch to the passenger side. You could use a small block with a big block A/C evap. housing.

I tried to find a picture with a Big Block housing and I couldn't find one.

[bcvet]

Skylark,Ventura,Omega or nova
Should bolt right in

[mark x22]

silver car is small block , orange is big block

[sleepsinshed]

The suitcase comes in two pieces, the inner cover and the outer cover. The outer cover is the same whether it's a BB or SB. The inner cover for the BB has a relief in the bottom part for extra clearance. All you need is to replace is the inner cover. From TJS69's previous post it looks like they're finally reproducing this part.

Note also that the POA valve is on the inside of the suitcase on the BB, and on the outside on the SB. You might have to make some adjustments for this.

[TJS69]

Originally Posted by sleepsinshed

The suitcase comes in two pieces, the inner cover and the outer cover. The outer cover is the same whether it's a BB or SB. The inner cover for the BB has a relief in the bottom part for extra clearance. All you need is to replace is the inner cover. From TJS69's previous post it looks like they're finally reproducing this part.

On a 1st gen. camaro Both the inner and outer cases must be changed.

You will need both an inner AND the outer. I am not sure if they reproduce the outer ones yet.

This is from a 2003 NPD catalog.



I can not find where an outboard is anywhere ! (Reproduction that is.)

[Unreal]

Originally Posted by TJS69

The angle of the box from the firewall is different between a small block car and a big block.
The small block angle is about 45° and a big block is about 60°.

I'm certain that the outboard half of the case is the same for sb and bb. The only difference is the s/b has the POA valve bracket attached to it, where the b/b has it attached to the inboard half. I used an outboard half from a s/b, and an inboard half from a b/b. If the angles were different, that would not have worked.

BTW, I might have an outboard half. PM me if interested.

[click]

check with www.oldairproducts.com in Texas, they might have what you need.

[TJS69]

Originally Posted by Unreal

I'm certain that the outboard half of the case is the same for sb and bb. The only difference is the s/b has the POA valve bracket attached to it, where the b/b has it attached to the inboard half. I used an outboard half from a s/b, and an inboard half from a b/b. If the angles were different, that would not have worked.

BTW, I might have an outboard half. PM me if interested.

Please Look at the pictures in post #7, showing the two angles.

[Unreal]

I know they look different in the pics, but original 1st gen outside cases are absolutely identical, except for the presence of the POA bracket on the small block.

[TJS69]

No disrespect, but NO ! The portion of the outboard half is bolted to the firewall, and houses the blower fan. That means the portion that houses the evaporator, must be at an angle to the firewall. The above photos clearly show that difference. The reason for the different angles ? Well, if you tried to use a small block one, it would hit the larger and offset engine !

I have a small block set if you need more photos. I do not have a big block set to compare.

[mark x22]

The big block box is 1/2 inch longer on the seam between the two halves,and the screw closest to the firewall is 3/8 difference , between screws is the same .