comparing C2's to C4's..
 

are acceleration figures different? how about from 1995 to 1996..any changes in 'listed' performance with the new varioram? looking at a '95 C2 and '96 C4 and wondering how they compared in book numbers..and 'butt-o-meter' should anyone have any anecdotes.. ;)
ryan

There is very little difference between the book numbers. However, look at these two cars individually, on their own merits, because I'd wager that is probably in better condition than the other and will perform better. In other words, just like identical 69 T-210s, it's possible one will perform better, consume less oil, and generally be a better one to buy compared to the other.

Short story--look for the best example of the 993, not the best model of the 993.

The Varioram car will have a little more oomph in the midrange, you can feel it when it comes on. But overall, the 95 and 96-98 cars are very similar in performance and feel.

There's a difference in feel between the Carrera 4 and the Carrera 2, of course, even though most of the time the C4 is putting 96 percent of its power to the rear wheels. I've had a couple of Carrera 4's and really enjoyed how planted the car feels in the rain (and, yes, the snow, too).

I haven't driven a non vario 993 but there's not a huge HP difference. I can say that when the vario kicks in, it peels your eyelids back. If you end up with a 993, one must do mod is the LPMM. Look that one up on Rennlist.

The AWD on my C4S is really transparent. Most people would never know it was there.
http://forums.pelicanparts.com/uploa...1167365884.jpg

jeff and mark...both sweet as hell C4's. i'm looking at a '96 C4 cab in virginia that's black, but not nearly as pristine as yours, jeff. yours is outa my league right now. i'm looking at a 90-95K miles car..
ryan

Ryan -

Best of luck to you. If you have any questions about that one in Virginia, feel free to PM me. I'd be happy to help out if I can.

Jeff

thanks, jeff...much appreciated. haven't heard back from the guy yet..
ryan

Email reply sent.

bigchill... if you can, try to drive at least several examples of 993s... before you buy one. This advice was given to me when I was looking, and I did drive probably 8 cars.

All were quite different....I purchased the quickest one, the one that felt the best and had the best service records....but without having driven the others, I would have not had a point of reference. It was hard to believe, but like snowflakes...it seems that no two 993s are exactly the same.

sonic..thanks for the depressing news..ha! seriously, here in arkansas (don't know where you are), it's gonna be a challenge to try a lot of different 993's without getting on an airplane. :(
ryan

looking at a '90 C4 cab with 160k on the clock. this description:
Features: A/C: Front, Cruise Control, Power Locks, Power Steering, Leather Interior, Power Seats, Airbag: Driver, Airbag: Passenger, Alarm, Anti-Lock Brakes, Fog Lights, Power Windows, Alloy Wheels
Selling Points: One of the best kept, 1990 911 C4 Cabrios avail for purchase. Any qualified PORSCHE® authority will tell you that it has 161K hwy mi is anything but negative, considering the very unique service & maintenance history. Most of the less than 10K annually average mi, been put on by the orig Beverly Hills owner, using this beauty to drive down to his practice in the south LA. Serviced exclusively by PORSCHE® authorized dealers, the last, its 150,000 mi service, completed by a CO PORSCHE® dealer. The records show all services incl the 135K mi full service. At 97K mi, the complete clutch assembly was replaced with new parts and seals. Receipts for this very costly repair are on hand with all other receipts. At 104K mi PORSCHE removed the engine, serviced & all seals replaced to eliminate a small leak Since I have been the owner, I had a new alternator installed & the clutch replaced & I had the car lowered by EIBACH & upgraded to the PORSCHE® Turbo Alloy Wheels.
Condition: The interior is in excellent condition. No cracks on the dash and the special order “Supple Leather” still feels very soft. As the pictures show, the exterior is in awesome shape, shimmering from head to toe and truly looks stunning.


all other things being equal, how did the performance of the '90 964 compare with a '95-96 993 model C4? numbers close?
ryan

Ryan -

Instead of considering performance, I would consider reliability of the 964 C4 vs 993 C4. The mechanisms are ~completely~ different!!

anyone care to comment on what jeff says concerning the different awd mechanisms between the 964 and 993 C4's?
ryan

From what I understand the 964 uses a mechanical differential to split the power between the front wheels (39%?) and the rear wheels (61%). The PDAS computer can lock the rear differential if rear slip is detected and also lock the center differential in case of wheel slip. The front differential is open and can not be locked. The center and rear differential can be manually locked using the switch on the center console making it a 50/50 split. If the PDAS computer fails the car is still AWD, just the traction control function is lost. The 964 C4 also has a very high pressure brake system vs. the C2. Because of the high pressure brake system I've heard you need a Bosch Hammer to properly bleed the system.

The 993 system is also mechanical except that slip is controlled using a viscous coupling in the center and rear differential. As the front or rear slips fluid is heated in the viscous coupling which starts to "lock" or transfer power to the other wheels. I think the split was changed to be normally 15% front and 85% rear. This setup is a lot more simple but probably does not work as well in deep snow or sandy conditions.

From what I've read the 964 system tends to induce more understeer while the 993 system is largely transparent. I can't remember if the regular 993 C4 had the high pressure brake system, I know the 993 Turbo did.

There is a great article by Adrian Streather over on Rennlist regarding the C4, that's where I got most of my 964 knowledge.

Good explanation, Blue. (Pilot??) The 993 C4 uses the electro-hydraulically boosted brake system that the turbo uses.

InTheAir-

Thanks for the info on the C4 brakes, too many numbers in my head!

Yes I am a pilot, my instrument instructor always told me to keep the blue side of the artificial horizon up. Good basic advice!

former lear driver here...lear captain for air cargo companies and an air ambo outfit for years. blue side up...good advice.. ;)
ryan

Definitely. :) As long as that vacuum pump is working. ;) ;)

Jeff
Private Pilot
Land/Sea
Instrument Rated
HP/Complex

Yeah those vacuum pumps can be a pain in the butt. I've only had one fail but it was during IMC on the procedure turn for an ILS! The airplane I fly now uses laser ring gyros that are extremely reliable, the main problem is the screens failing.

Jeff- I like your photos, what kind of equipment are you using?

Big Chill have you found your car yet? I've seen your threads about the 964s, seems like you're specifically looking for cabs. I like the look of the 964 and am in the same price range as you. It's either you find a beat 993 or a nice 964 in the low 20s. I have seen a few good ones go for the high teens.

Have you been able to drive a C4 yet? I've never driven one, just a couple C2s. I would guess it's tough to find a selection in your area.

Jess
ATP
Comm/Inst SEL
MEI

jess...you summed up my problem perfectly - beater 993's or decent 964's. i was determined to get a 993, but i just can't do it, so it's gonna be a 964 C4 cab when i find my car. and yeah..arkansas isn't just filled up with p-cars to try out.. ;)
ryan

Thanks.

Some photos were taken with:

Canon 10D
Sigma lenses

I now use:

Canon 20D
Canon "L Series" (Professional) lenses

993 c4 or nothing!
 

I just bought a 95 993 c4 cab with 110,000 miles which I picked up this summer ‘06 for $26,000 in triple black. I would say that the selling features of this car was the fact that it was a C4 and had the rear seat delete option (should have been standard in my opinion). For me it’s like it was just broken in and now ready for some serious mods. Things that were immediately wrong: needed a top and the power motor cables (although not that bad), valve cover gaskets, flywheel gasket, front breaks & rotors…I think that was about it.

993’s are the best of the air-cooled hands down. These cars are amazingly awesome! All the knowledge Porsche had acquired from the past is rolled up into this beast. AWD with power is a must unless you love doing doughnuts. They stick to the road like GLUE! I believe that the same AWD system in the 993 is in production for today’s Porsche. I wouldn't even think about a 993 c2 or a 964 anything. The 964’s had a crappy AWD system. The 993's are the most beautiful of all Porches including the current 997 (notice how they reverted back to the 993 looks).

I will caution if you're not a mechanic. Make sure the engine is in good shape. Porsche shops are not cheap. If it’s dripping oil verify where it’s coming from. A lot of the times it’s just the valve cover gaskets (simple cheap fix) but it could be a flywheel seal. In my case I didn’t look hard enough and it turned out to be a flywheel gasket. Since I was going to change the clutch and flywheel anyway to handle a supercharger I wasn’t that bummed. If it’s making noises it better have a great price tag. And defiantly verify it wasn’t crashed.

Over the next year I plan in supercharging it, adding the turbo flairs, skirts and a bumper with some fat 19” wheels and tires.
I'm debating on glass, graphite or factory steel for the rear.

Forgot to mention that the vario ram is not worth it. when i was researching the differences between a 95 to a 96-98. I found out that the 95's were the best for my needs. One: the HP gain is minimal. Two: 96 and on uses OBD-II. I read about several issues with the OBD-II system lighting up the dash with false readings. one was related to the valve covers. But don’t get me wrong OBD-II is nice for statistical info on the car.

Basically the cars are the same except the vario ram and OBD-II. 23hp and false readings. If you are going to mod stick to a 95.

So, here is my opposing opinion on two issues:

AWD: I have autocrossed a student's car, a C4S and it did not drive very well. It felt sluggish and the 4wd did not help me any, compared to my 2wd. So, unless you live in snow or crappy climate, you only will add weight and mechanical complexity.

The varioram IS worth it. While you may say that 35 (!) horsepower is not much - and sorry, that's in itself a bunch, the power comes in at a different rpm. It is not just the top hp / torque but the curve being a bit flatter as well. With a little help, you can easily get 300 crank horsepower out of the varioram - which may not be trivial on the 95, especially if you want more than just peak hp.

So, my vote is for the C2. I do think that the 95 is as good a car as the later ones. The CEL problem should be a non issue Arkansas, so more power to the varioram!

George

The 993 C4, unlike the 964 C4, can quite easily be converted into a C2. Selling off the parts should pay for the work. I would have to agree with aigel, varioram does make a difference. Like aigel said, it's not about achieving a peak HP number to throw about, but about boosting midrange torque.

One more thing:

If you are shopping for the wide body, the C4S has the advantage that it comes with turbo brakes and even suspension, if I am not mistaken. So, that may be a selling point, if you like the 4wd anyway. Of course I have an opinion here too and think that the narrow body is the better deal and that for not much (compared to the S premiums), you can install big reds and an updated suspension. ;)

George

But why convert a C4 into a C2? The only time it could possibly be justified is a 993TT.

Just sell the C4 and buy a C2. No need to bastardize a C4.

Or a C4S.

George

People are paying more for 993 C2S, when you can have more for the money in a 993 C4S, which comes with big reds. Some people disparage weight/handling of the C4, when the weight can be removed and the handling be made rear-wheel drive. Not that this is what I will do.

It's a theoretical question, but I think a C2S with a big red and suspension upgrade is probabaly a cleaner approach than a C4S with the front wheel drive removed. ;) I certainly would go the cheaper route, as the final product is all that counts!

George

I removed front wheel drive completely from C4S and it's quite an easy job,you only have to buy 2 wheel nuts (I hope that's the term) that hold the wheel together instead of front drive shafts (that's an original fir from any C2)

Luka