1979 turbo questions

[fredmeister]

I am looking into purchasing a 1979 930 turbo and had a few questions on component parts to get an idea on maintenance/rpelacement costs.
1) The front brake rotors on the 1978-1979 model year appear to be 3 times the price of later turbo rotors thru 1989. Why is this since I thought they all turbos after 1977 used the 917 based caliper system? Were they floating rotors for those 2 years only,(just a guess)
2) Clutches seem extremely expensive and I did not see a listing on Pelican for a Sachs center spring clutch kit. Just the stock rubber centered clutch....which is the reason to replace it in the first place with a spring centered unit. Any info on the availablility of spring centered clutches for 1979?
3) Plug wires for turbo are the same as for 1978-1884 911SC correct or not?
4) Availability of short shift kit for 930 4 speed....who makes best unit?
5) Stock tire sizes for 1979 turbo, I assume they have 7 and 8 inch 16" Fuchs wheels stock, but what tire sizes should mount? Please correct me if wrong.
6) What was max boost level stock for this year? Horsepower I heard was 255, correct or not?
Thanks in advnace for the info.
6)

[Slant930]

1) Yes I am pretty sure only the 78-79 had the floating rotors.
2) Yes there is a spring center clutch you can use. I am pretty sure the disc is the same one as the SC's.
3) If you replace the wires go with Magnecor instead. Cheaper than oem and work just as well, if not better. Eliminates that stupid braiding also. I have run these for a couple years and never had issues with them.
4) Weltmeister is the most prevelent, but there is also a factory short shift kit. Apparently its hard to find, but rumor was Wayne might try to get these in here at Pelican. Weltmeister one is ok. Whatever you try the 930 4spd still shifts likes an old truck.
5) Yes 7 and 8 should be the standard, probably with 205's and 245's? Not sure though.
6) Max boost level was approx. 0.8bar. Horsepower should be 280 at the crank I believe on US models.

Timothy

[fredmeister]

BUMP!

[sprbxr]

To get rid of the Rubber clutch disc, you need to backdate the clutch assembly to the pre 78 style clutch. You will need a spacer for the ring gear and a modified TO bearing.

If you want to start cranking up the boost, you will need a bigger Intercooler at the minimum. It is a good idea to go with headers too. Make sure your AFR is not too lean or you will have an expensive paperweight.

[beepbeep]

Originally posted by Slant930

2) Yes there is a spring center clutch you can use. I am pretty sure the disc is the same one as the SC's.

nope. It's a 240mm clutch...bigger than SC. Rubber-damped clutch is prone to fail (if old) but it mostly happends old clutches. If you install a new rubber-damped clutch you will be OK for long time.

Boost is 0.7 or 0.8 bar (depending on who you ask). It can be raised to approx. 1.0 bar with stock IC, dunno about CIS. ROW 930 CUIS will handle 1.0 bar w/o problem, dunno about NA version (I've heard they got smaller fuel unit).

Discs are full-floating type, fitted only for two years.

[89911]

Fred, there is no escaping those rotor prices. The 79 car came with spindles and housing simlar to the narrow body car. They made rotors to fit these for only a couple of years and they are in very short supply, hence the cost. Other companies make a rotor to fit, these are what I use on my 89, but they are still pricey. Instead on a 79, get an 89 turbo and all this will be solved!

[kycarguy 935]

1978,1979 and 1980 930's had the floating rotors.

[Slant930]

Thanks Goran for correcting me on the clutch disc. I'm still learning....