I installed my new oem style heater hose and fitting kit on my L78 per the assembly manual and guess what. The assembly manual shows that on big blocks the large heater hose goes to the intake manifold fitting. Thats what I did and now I think that I ruined a very expensive set of hoses. I referenced a photo of an origional ZL1 taken by Roger Huntington taken in 69 that shows the "GM" marked hose to the intake fitting. Now I think that was wrong to. Any thoughts or sympathy? Thanks

The heater hose with GM and the square, or triangles on them are, for the most part repros, they were not used on the Camaros originally. Although there were a couple of changes in the type of hoses used during the 69 model year most hoses don't have any writing on them. Most of the surface of the hoses are smooth but there is a set of 3 or 4 grooves and ridges that run lenghtwise down the hose.

My concern is with the hose routing. I set it up with the larger hose going to the intake manifold fitting per the assembly manual. After doing this I noticed that most cars had the big hose going to the water pump, What is right? What will happen if I run the car with the hoses reversed?

Originally posted by restoman:
What will happen if I run the car with the hoses reversed? Maybe you will get A/C for free! :D

Sorry - couldn't resist. If my feeble brain remembers correctly - the large hose (3/4") goes from the top of the heater core to the water pump, could be wrong - but, that's my recollection.
Maybe one of the COPO or specialty vehicles sites would have the answer for sure.

I think the draftsman screwed up on the L35 heater hose page. Big heater hose always runs fron the water pump to the top connection on the heater core. Small hose always runs from the bottom heater core connection to the manifold connection.

http://www.icehouse.net/camaros/slvrcopo.htm

http://www.icehouse.net/camaros/mycopo3.htm

Somewhere around here is a post by JohnZ explaining why the hose sizes are different and why they are connected the way they are.

Here it is:

http://www.camaros.net/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic;f=5;t=001459

Thanks, now i know why I got that assembly manual so cheap at that swap meet