dbelleperc

I've heard of the 993 exhaust fitting in the standard body 964. I was wondering how it's done, and what parts you need to make, or buy beside the exhaust and left rear valence panel with the exhaust cut out.

Bill Gregory

David,

The key thing that needs to be done to the 993 exhaust is that the exhaust flanges on the right hand bank have to be turned to line up with the exhaust studs on the 964. Easiest would be to cut/turn/weld.

pzull

Someone's done it. Here's the URL:

<a href="http://www.stig.uklinux.net/media/993exhaust.pdf" target="_blank">http://www.stig.uklinux.net/media/993exhaust.pdf</a>

Nick Appleton

Here's a rear valance panel for sale on the German eBay site to allow for the extra tailpipe

<a href="http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=2402196519&category=14767" target="_blank">Rear valance (in German!)</a>

Cheers

speedster 94

hallo
The Flanges and Bumper is the least issue , you have to change the Oillines as the are to close to the 993 Cat, and you have to rework the Mufflers to fit them under the rear Fender/ Bumper
This is not a simple Task , i have done it a few Times , last week for the last Time .
harald

Kevin

Friends;

This is a very worth while endeavor. Harold went with the muffler modification route. It is far easier to remove 1/2" of material from the muffler support brackets and reweld them. I would be willing to provide pictures and conversion steps for someone that would host it. I have personally done 4 of these conversions. If you need to have Cats, and do not want to spend thousands of dollars for an aftermarket system, this is the way to go. I must stress that one must study the 993 exhaust system to see what really is involved. The benifit to this system is that you can get parts for it everywhere. Used exhaust sytems go for $400.00.. I typically have $600-700.00 into my system. Thanks to Pzull for the link.

dbelleperc

Hey Kevin,
Can you E-Mail me the pictures and convertion steps on how to adapt the exhaust if you could. Thanks.

Dave R.

Kevin,

Great stuff.

Do you find that the conversion makes the valves and spark plugs harder to access and adjust/replace? Judging from the link Pzull posted, and looking at part diagrams, seems like one would only need to pull the mufflers and the elbow tubes (number 9 in the 993 PET diagram) to access the valves, although the extension of the headers laterally toward the sides of the car (the 964 headers don't extend laterally) might make things a bit tighter than with stock arrangement.

Any problem routing the O-sensor cable to the new location?

Did you have to discard or trim the stock 964 composite heat shields (like three vertical sides of a box, directly opposite the heads and along the back of the motor)?

Regards,
-Dave
'90 C2

Kevin

Dave;

When doing a valve adjust on our 964's alot of time is required to remove the exhaust anyways. All that is needed now is to remove the mufflers. Which is such an easy job. The 993 heat exchangers are smaller and lighter than the stock 964's. I did remove all the side heat shields that the 964's have, however I used the 993 heat shields where I could. The main concern is to shield the Cat. The 993 airtube sits right on top of the cat and heat that soaks into the airtube dissipates.

The O2 sensor is an issue, however I just grabbed an old sensor that I replaced years ago and added 24" to it, it is not a issue. The 993 O2 sensor is located right in the center of the Cat. This is another reason why I recommend the Non VRam &lt;96 exhaust systems.

Dave R.

Kevin,

Thanks.

Another question regarding the cat. As Harald points out, the rearmost oil line would sit near the 993 Cat. Did you wrap additional insulation around the oil line, or otherwise protect the oil line or shield the Cat?

Regards,
-Dave

Kevin

Dave;

Do not use the stock oil line. Pain, Pain, heat=failure. I can not tell you as to how many of the stock 964 oil lines have been replaced because of leaking. In order to beat the heat, buy the early '74 vintage oil line (all steel) that runs to the rear of the engine, it curves under the bell housing. You will have to make up a new oil line that will connect that line to your oil canister. It is a must.

pzull

Hi Kevin,
What material is the stock oil line made of if not steel? Mine is definitely metal but I don't know if it's steel?
I'll also be putting in an equal length header system with twin outlets similar to the 993

Thanks

Dave R.

Pzull,

If you look at the bottom of this <a href="http://www.msroadrace.com/TechStuff/TechIllustrations/964/1engine/OilTank1-04-01.jpg" target="_blank">picture</a> you can see that the oil line running from the scavenge pump (not shown) to the oil filter housing 47 appears to have a rubber section (which is sleeved with insulation 55) where it runs over the primary muffler (not shown) at the rear bumper.

I think that is the section Kevin is referring to.

pzull

That's strange. My oil line looks nothing like that.

Here's a pic with superimposed graphic of my intended exhaust system:
<a href="http://pzull.tripod.com/porsche964/id6.html" target="_blank">http://pzull.tripod.com/porsche964/id6.html</a>

johnfm

Is the 993 twin outlet exhaust any better than a 964 system with cat bypass and primary bypass??