bruce7

This thread is about how to eliminate the rear heater blower assembly and
replace it with the RS heater bypass option.

What motivates this DIY for me is that recently I did some tuneup work on my
993 and in the process found myself removing and installing the rear heater
blower assembly way too many times. Over the years some of the fasteners have
become stripped and the installation is fussy at best.

Considering the fact that I use the heater maybe 3 times a year here in Southern
California and don’t normally encounter conditions where quickly clearing the
windshield is necessary, I thought it might be worthwhile to try the RS heater
bypass option and see how that works.

Long story short, I think it is a great idea, and specifically I’m talking about my
situation. It might not work for others and you will have to decide that yourself.
But if it does you will realize some nice benefits.

One is the reduced clutter in the engine compartment. Reduced weight as well.
The ability to quickly get at the left side of the engine is really nice. This makes
it easy to quickly get at the vacuum lines and connections for testing which is
something you have to do all the time with this engine. Other maintenance tasks
will be easier and faster with the rear heater blower gone. It literally takes 5
seconds to remove the hot air elbow and get started working.

I boxed all the parts up and put the rear heater blower assembly into storage just
in case I need it someday.

To help seal the the NTC temperature sensor and rear shift flapper valve
connectors, I sourced some injector connector parts from Ballenger Motorsports
in VA. The part number is CONN-85571 if you also want to go this route. This
should help prevent the elements from getting at the metal connectors if I ever
need to return the rear heater blower assembly.

The Porsche parts all came from Sunset Porsche.

DIY instructions are attached and the photo album can be found here:

https://plus.google.com/photos/11229...PaQlvO9pse7jgE

jg291446

Thanks for posting! I will do it soon and was going to post the DIY but you did it better than I could.

But can you specify which bolts (and where) need to be removed to remove the blower? I heard there is only 2 but not sure where.

Thanks again!

redlightrich

Thank you for taking the time to post a thorough how to, including part numbers.

These type DIY instructions can really help people who are "on the fence" as to whether or not they can or should do it themselves.

These posts have a tremendous value to the community.

Thanks again

Rich

bruce7

Yes I will post a few more pics to show those bolts later today. There are 2 bolts that hold the blower motor to the manifold.

Sent from my iPhone using IB AutoGroup

bruce7

Here is that photo I mentioned that shows where those two bolts are located.

-bruce

uniquenamehere

Pardon my ignorance, but what does this blower motor do? You're not completely without heat are you?

nine9six

Hey Bruce,
You know how we all are about photos. How bout a pic of your cleaned up engine compartment!
TIA,
Paul

bruce7

The main function of the rear heater blower is to act as an auxiliary blower
for the front 2 cabin blowers (fans). The front fans suck the hot air forward
and the rear fan pushes the hot air forward.

The term "heater bypass" may be a misnomer but that is how people refer
to it.

I am not without heat as the engine fan pushes hot air forward, but with less
force than the dedicated auxiliary blower.

Fabspeed has an interesting video about this subject and their own product
which you can see here: http://www.fabspeed.com/993-carrera-...t-bypass-pipe/

bruce7

OK! Since you asked, here are two pictures from the photo album linked
to in the initial post.

-bruce

OverBoosted28

Perfect timing. Mines in a box in the garage, waiting to be installed. Just waiting for bridge relay to arrive. I know "could've made a jumper", but I like the clean faux relay.

bruce7

I agree, it makes a nice clean install. Shoot us a pick when you get it installed.
I'd like to see how it looks in a turbo.

-bruce

OverBoosted28

Will do, but not much to see since it's all buried under the intercooler.

uniquenamehere

Excellent...thank you for that!

Coop

FYI on this, take your time. I had to Dremel off 1.5 inches of carbon fiber and re fit to fit after fitting. It works very well, especially with the 964 coded fuse, but is certainly not an easy install due to the bend at the base of the pipe. PM me to find out...

RichPugh

Pardon my ignorance but, what is the purpose of the bridge adapter in place of the original heater relay?