What's a 1993 964 got that a 1991 doesn't?
 

Beyond the LUK dmf, cylinder gasket, and dual distributor vent that is.
I'm closing in on a C2 and want to know a bit more about the upgrades.
I believe the brakes are different.
Is the interior different?
How about the suspension, etc?

Tear drop mirrors and Cup wheels.

Unless it is a turbo, they have the teardrop mirrors and cup wheels...

Yes, that's right. And with the 17" wheels a 10mm steering stop.

What else could Porsche have improved to help.

Does anybody know:Are the front brakes unchanged? Did they go to red calipers?

Were the windshield wiper arms upgraded 1993? I think someone said something about double springs.

Are the door thresholds and latches changed?

My 93 has black calipers.

The rear brakes on the C2 were changed from 2-pot to the same 4-pot calipers used on the C4. All 964 calipers are black as standard apart from the Turbo 3.6 which had red.

Air bags and the consequently revised interior/dash were standard by '93 but I suspect that even the US '91 cars had airbags. It was only the RoW cars that waited until around '92 to get them.

The dual spring wiper arms were certainly a late addition but I don't have any details about the introduction date.

I'm not sure the distributor vent ever reached a production 964. I've certainly seen very late cars without it. I think it may have only been introduced in production for the 993.

Regards

Dave

Didn't the intake change from aluminum to plastic in late '91 or '92?

993
 

The most important difference..headgaskets!!!!!!!

R-134a air conditioning ('92 and earlier was R-22).

Every single change can be found in Adrian Streather's book on the 964. If you are trying to understand 964s, you need to buy that book.

Don't say R-22, it was R-12 for the air conditioning.

Mark

Oh yeah, head gaskets and refrigerant. And the A/C conversion required different components too, do you know what they were?

As for the Streather book, good point, I am wait listed. Our host is back ordered but I tried here first a couple weeks ago. Anyone got the corresponding info?

Whoops...and I already also received an admonishing PM from a Mr. A. Gore. (sigh)

Not sure what the exact parts for the AC conversion are; I think on the Rennlist 964 forum there were a couple long threads on the topic.

I had just read a story about a guy who used R-22 (home and commercial building refrigerant) in his car. The compressor seized, broke the fan belt, car overheated, and blew a head gasket. I'm not being politically correct here, this is a safety issue.

The conversion can be done one of three ways:
1) If your system is empty, remove the fitting that allows you to add R-12 and install the R-134a fitting. The fitting is about $11.50 here: A/C Adaptor Kits & Fittings
Recharge the system with the correct amount of R-134a.

2) Have the system professionally ($) evacuated, replace the receiver-dryer, change the fittings as above, re-evacuate the system, replace the 4 oz. of compressor mineral oil with R-134a compatible PAG-46 oil, and recharge the system with the correct amount of R134a, about 30 oz.

3) Buy the kit from our sponsor, P/N 10-7504-128-M207. Then recharge the system as above after a vacuum evacuation.

Good Luck,
Mark

Second-hand knowledge:

92-94
More clutch pressure plate clamping force, and less-stiff spring rates too...

+1

Did the windshield wiper arms go to 2 springs each?

My advice is, unless you need a nice coffee table book, cancel your order. That book is worthless.

I have to disagree with your opinion.

I believe shock mounts changed slightly after 91

+2 on it being rather useless.

Great if you want to know some info regarding MY differences but after that it's VERY light on any how to. He also goes on and on about how you can't use 18" wheels on these cars yet everyone I know who Club Races this series 911 runs 18"s.:confused:

I have it. Nice to have but you get more detailed information from here and RL (plus you can ask questions). :)