rickc

I have been toying with the idea of installing a set of 993 cam towers on my 3.3 . I have been told by several sources that it's a nice retrofit that virtually eliminates the need for frequent valve adjustments. On the downside, what's the performance loss for going to a hydraulic setup? I certainly don't want to put together a twin turbo motor, go through this whole retrofit process and then float my valves.
Rick
'78 930

Kevin

Rick I have done the conversion. It is a real easy install if you have access to a good machine shop. You will have to tap the oil outlet galley. You will also have to plug the EGR ports. The other benifit is no leaks on rocker arms and if you do break a rocker arm you just unscrew 2 allen bolts. If you have a older engine I wouldn't do it. You have to run a thinner oil, so a additional oil cooler might be in the mix. The hydraulic are very sensitive, and must have clean oil.. Go for it. Also, you will have to use the stock 993TT camshafts and purchase the 993 rocker assy. If you have a K27 7200, you will be fine, your torque curve shuts down around 5K anyway..

rickc

kevin: I have the complete 993 cam tower setup with cams, rockers,covers,etc. Is there an advantage to going with the 993tt cams over the standard 993 cams? I believe the lift is higher on the non turbo cams. I am completely rebuilding the 3.3 engine...were you worried about contamination from an older engine? I will using two modified K-16's
Will this valvetrain handle 600+/- hp?
Rick
'78 930

Kevin

The lift and cam duration is higher. You are running a EFI correct? If your displacement is only 3.3 you might have a little to much camshaft for your engine. Also, you might want to think about keeping the K16 is the stock form. You can always upgrade the wheels later. Lately there have been a few twin engine that have went with the GT1 config, and there isn't enough displacement to get good boost at lower RPM's. Since I take it that you are going to a twin setup, you will have the oil supply feeds right at the cam housings for oiling the turbo's...

rickc

I will be changing P&C's to 3.4 and using the motec M600 with twin intercoolers. Since I am using a non turbo cam tower setup, I am unclear how to make the tap from the cam towers to the turbo tanks. If I were to but a 993TT oil line setup, do you think it would be clearer, or should I just make up my own oil lines? I am also relocating the oil tank with a C2 setup. I have been unable to find a picture or refernce that shows how the oil setup is to work. I will be using 993TT headers, so the turbos should be in the right location.
Rick
'78 930

Kevin

The 993 and 993 cam housings are the same, the TT oil line setup is very clean and easy. However, I would modifiy it by making my own lines and purchase the 996TT anti siphon check valve that screw into the turbocharger oil inlet. This reduces the smoke at startup.. Using as many factory pieces make your job easier. Are you planning on using the factory 993TT front sump? The 930 pump won't pull enough oil from the 2 sumps..

rickc

Does anybody have a picture of the oil line configuration from the cam housings to the turbos? I guess I need to look at finding a 993TT front sump! What's the best way to purchase one of these?
Rick
'78 930

Kevin

You should go to the dealer and order the pump.. Factory item only.

rickc

Ouch! How about the oil lines...any diagrams or pictures?
Rick
'78 930

PorschePhD

Here ya go. You can see the bridge and the line coming off of it to the turbo.

rickc

Stephen:
Nice looking engine! Thanks again...That's pretty straightforward looking. Get one for each side and I am in business. Kevin also indicates that I should pick up a 993TT oil sump to evacuate the oil tanks...anything tricky about that install on the 3.3?
Rick
'78 930

PorschePhD

Here is the mod to the int shaft.

PorschePhD

You can see above where the drain back into the case is. That is what I am pointing at. This picture is the whole pump.

Kevin

Stephen forgot to mention that the intermediate shaft mod was done WITH the engine Together... Not for the faint at heart! But it can be done.. His pictures show it, and tell it! Yes, buy the factory pump, you will be far better off.. You will also have to buy the drain back/sump tube that Stephen has shown..

rickc

Stephen and Kevin...thanks for making this clearer. I was very frustrated with some of the factory diagrams.
Rick
'78 930