Will these Factory 19" 997 C4S rims fit on my 996 C4S
03-19-2018, 07:21 PM
#16
Out of curiosity, what are the widths on the fronts and rears? Just bought a set of 19s from a fellow RLer this winter and will be throwing them on soon after a little refurbishing. Looks like you got one heck of a deal if they clean up nice.
03-20-2018, 01:22 AM
#20
Man, those Porsche engineers are dumb. Putting in an AWD system that doesn't work. Stupid. I'm sure someone smarter then me will chime in but I'm pretty sure the AWD was not done to be better in the snow.
03-20-2018, 01:35 PM
#21
Know how this all came about? Because I thought the same thing you did, so I jacked my car up off all four wheels and and put it in gear, all for wheels spun, yay, it works! Right? I told my indy porsche mechanic that and do you know what he said? He laughed and said, yeah but did you try to stop it with your hands? Huh? Yeah he said, the wheels may spin off the ground, but there is no real torque going to them, so you could stop the wheel spinning with your hands and a pair of cotton gloves. So I tried it again, and sure enough he was right.
Again, my car was 14 years old with 59k miles on it, but I also just showed you 4 videos of other cars with the exact same thing....
03-20-2018, 01:45 PM
#22
Nothing is perfect and everything fails at some point (there have been books on the IMS can of worms, the numbers and percentages are worth looking at), and to each their own as far as modding your car. Try putting on those cotton gloves and put them over a light bulb, it block the light but it doesn't meant the light is not shinning and we don't go around taking out light bulbs 
03-20-2018, 02:25 PM
#23
Nothing is perfect and everything fails at some point (there have been books on the IMS can of worms, the numbers and percentages are worth looking at), and to each their own as far as modding your car. Try putting on those cotton gloves and put them over a light bulb, it block the light but it doesn't meant the light is not shinning and we don't go around taking out light bulbs
For the record I'd love to be wrong; I'm literally invested into a car that I hope is worth more and has added functionality. Unfortunately, I am just not seeing any evidence at all that that is the case, and I tihnk others agree. Would love to hear others opinions or evidence. I also believe its entirely conceivable that like an LSD, it worked in the beginning but now no longer does. The difference is of course that our front diffs are not serviceable, and supposedly lifetime, and everyone knows an lsd needs to be checked and reclutched.
03-20-2018, 03:24 PM
#24
Rennlist Member
Hey brother, thought I'd chime in because it looks like you're looking for some info/experience. I have an '03 C4S coupe 6spd that had 59k miles on it when I bought it last summer. I was looking for a C2 for the RWD, but a deal came up I couldn't pass up (plus, why say no to 'dat wide-booty).
Anyways, always thought the idea of an AWD Carrera was silly, since I wasn't going to be winter driving mine anyways. It's a 3 hour, bolts only operation that is completely reversible, and it's fairly well documented that removal of the front drive train is minus 80 lbs and plus 11 AWHP. That's -80 lbs and plus 11 hp, for free?? Most of us are willing to shell out $800 for an NA tune that may or may not add 5 whp, so sign me up!
My point is, yeah, go ahead and do it. Loose the weight, and gain a few horses is you want the car to feel a touch sharper. The grip wont feel any different for you after, because it isn't, which is great! I think it sharpens up the car nicely, and combined with a GT3 TB, plenum, tune, pss10s, lightweight battery, exhaust, underdrivepulley really made my car feel like going from lackluster to nice and sharp (my car dyno'ed 293 rwhp and 254 rw ftlbs too!).
Notes:
1. While it is "reversible" you will most likely destroy your axles figuring out how to separate them, unless you know some sort of way to repack those bearings and put the snap ring back on. Better to wait to find a pair of "stub" axles for sale from one of the turbo guys. I torched mine, because I don't tolerate snap rings. Or have the correct pliers.
2. It is possible the car does in fact understeer more now that 80lbs is missing from right in front down low and all the way forward. I countered this by adding camber, and using more awesomeness (throttle). Full tank and spare also works.
3. Turns out when you get cabin fever and throw the ol' skis through the sunroof for a 135mph trip to vermont, these cars actually do pretty great in the snow. I do believe it's because all of the weight over the rear axle, even with 300 tread wear summer tires. (I even went out and bought those super zip ties, because i thought for sure I'd be getting stuck in the parking lots, but didn't)
Anyways, always thought the idea of an AWD Carrera was silly, since I wasn't going to be winter driving mine anyways. It's a 3 hour, bolts only operation that is completely reversible, and it's fairly well documented that removal of the front drive train is minus 80 lbs and plus 11 AWHP. That's -80 lbs and plus 11 hp, for free?? Most of us are willing to shell out $800 for an NA tune that may or may not add 5 whp, so sign me up!
My point is, yeah, go ahead and do it. Loose the weight, and gain a few horses is you want the car to feel a touch sharper. The grip wont feel any different for you after, because it isn't, which is great! I think it sharpens up the car nicely, and combined with a GT3 TB, plenum, tune, pss10s, lightweight battery, exhaust, underdrivepulley really made my car feel like going from lackluster to nice and sharp (my car dyno'ed 293 rwhp and 254 rw ftlbs too!).
Notes:
1. While it is "reversible" you will most likely destroy your axles figuring out how to separate them, unless you know some sort of way to repack those bearings and put the snap ring back on. Better to wait to find a pair of "stub" axles for sale from one of the turbo guys. I torched mine, because I don't tolerate snap rings. Or have the correct pliers.
2. It is possible the car does in fact understeer more now that 80lbs is missing from right in front down low and all the way forward. I countered this by adding camber, and using more awesomeness (throttle). Full tank and spare also works.
3. Turns out when you get cabin fever and throw the ol' skis through the sunroof for a 135mph trip to vermont, these cars actually do pretty great in the snow. I do believe it's because all of the weight over the rear axle, even with 300 tread wear summer tires. (I even went out and bought those super zip ties, because i thought for sure I'd be getting stuck in the parking lots, but didn't)
I am curious on one other thing though -- what got me into a 996 in the first place was a week i spent in one last year that made me fall in love. Particularly the steering. While it's a very different car from the air-cooled cars that came before it, the 996 still has that 911 steering feel that is like no other. I just don't get the same thing from the C4s. Would you be able to speak to the delete giving a much more C2 type steering feel? I can't see how it wouldn't, but until i do it myself (or drive a deleted car), i won't know.
Just spoke with Vivid Racing. They are the correct offset for my car, shod with 305/235 Pilots, and I just got the deal of the century! I also got a full spare set of lug nuts. I will post pics when my car arrives and I bolt them on and post some feedback on the RWD conversion.
Question: I like the look of the BBS caps vs the Porsche ones. Does anyone know the proper BBS center cap size for these rims? 70/64mm? (They went straight into my storage space and didn't remember to grab one.)
Thanks again everyone! I can't WAIT to get my new DD (IMS/RMS, Clutch and flywheel is already done 66K original miles!) All services and fluids are up to date. I'll just give it a quick once-over on a rack maybe get it aligned, start saving for coil-overs (Maybe H&R or Ohlins) and enjoy my new C4S RWD!
-Ryan
Question: I like the look of the BBS caps vs the Porsche ones. Does anyone know the proper BBS center cap size for these rims? 70/64mm? (They went straight into my storage space and didn't remember to grab one.)
Thanks again everyone! I can't WAIT to get my new DD (IMS/RMS, Clutch and flywheel is already done 66K original miles!) All services and fluids are up to date. I'll just give it a quick once-over on a rack maybe get it aligned, start saving for coil-overs (Maybe H&R or Ohlins) and enjoy my new C4S RWD!
-Ryan
And apologies, i feel like i may have caused folks to poop all over your thread -- that was not the intention. To those thread poopers: I'm POSITIVELY CERTAIN that ANY Porsche engineer in Stuttgart is infinitely more knowledgeable than I about putting these things together. I'm certain the C4s was faster around the Nurburgring with the AWD than w/o.... that's not the point. I just like the idea of a 2wd 911, it's just that simple. I also love the idea of a widebody 911. And I can't realistically afford (and maintain) any other 911. And if orangeman and I ultimately do something to adversely affect the performance of the car but we enjoy it more, who the F cares? No one should, cause it's our cars and not your's.
03-20-2018, 04:06 PM
#25
Rennlist Member
There are plenty of examples of C4s going around tracks faster than their C2 counter-parts. Clearly the AWD system provides some benefits. FYI - when I was testing my new clutch engagement on jack stands the front wheels began turning immediately. Maybe in some of the earlier videos their AWD system was worn and not functioning properly.
03-20-2018, 06:00 PM
#26
Rennlist Member
I'd say functionality is certainly a potential issue. As part of the drivetrain, the AWD is a wear item that to my knowledge is not a service item, so yeah, I'm sure not all of 'em are functioning properly.
Had to touch this one last time as i thought it hilarious today's front page news story: 911's AWD SYSTEM CELEBRATES 30 YEARS OF PERFORMANCE
In that story, 911 head August Achleitner refers to the AWD system as a "hang on" front axle, meaning no power goes to the front wheels unless needed. So in those videos orangeman posted, either those systems were faulty, or the car's ecu didn't think power was needed up front, lol.
I did some reading about this system upon purchase, but never could find out when/how much power could be diverted to the front.
Had to touch this one last time as i thought it hilarious today's front page news story: 911's AWD SYSTEM CELEBRATES 30 YEARS OF PERFORMANCE
In that story, 911 head August Achleitner refers to the AWD system as a "hang on" front axle, meaning no power goes to the front wheels unless needed. So in those videos orangeman posted, either those systems were faulty, or the car's ecu didn't think power was needed up front, lol.
I did some reading about this system upon purchase, but never could find out when/how much power could be diverted to the front.
03-20-2018, 06:31 PM
#27
Rennlist Member
I'd say functionality is certainly a potential issue. As part of the drivetrain, the AWD is a wear item that to my knowledge is not a service item, so yeah, I'm sure not all of 'em are functioning properly.
Had to touch this one last time as i thought it hilarious today's front page news story: 911's AWD SYSTEM CELEBRATES 30 YEARS OF PERFORMANCE
In that story, 911 head August Achleitner refers to the AWD system as a "hang on" front axle, meaning no power goes to the front wheels unless needed. So in those videos orangeman posted, either those systems were faulty, or the car's ecu didn't think power was needed up front, lol.
I did some reading about this system upon purchase, but never could find out when/how much power could be diverted to the front.
Had to touch this one last time as i thought it hilarious today's front page news story: 911's AWD SYSTEM CELEBRATES 30 YEARS OF PERFORMANCE
In that story, 911 head August Achleitner refers to the AWD system as a "hang on" front axle, meaning no power goes to the front wheels unless needed. So in those videos orangeman posted, either those systems were faulty, or the car's ecu didn't think power was needed up front, lol.
I did some reading about this system upon purchase, but never could find out when/how much power could be diverted to the front.
03-20-2018, 07:20 PM
#28
I am curious on one other thing though -- what got me into a 996 in the first place was a week i spent in one last year that made me fall in love. Particularly the steering. While it's a very different car from the air-cooled cars that came before it, the 996 still has that 911 steering feel that is like no other. I just don't get the same thing from the C4s. Would you be able to speak to the delete giving a much more C2 type steering feel? I can't see how it wouldn't, but until i do it myself (or drive a deleted car), i won't know.
03-20-2018, 07:23 PM
#29
But like... ALL of them are faulty? Including the (at the time 3 year old 2008 997 C4S? Mine was faulty too? The system is 100% mechanical, and in a way not even mechanical in the traditional sense, but controlled by thermodynamics and the shearing of the fluids, ECU has nothing to do with it, unless I supposed applying brakes independently as part of the traction control system.
03-20-2018, 07:30 PM
#30
There are plenty of examples of C4s going around tracks faster than their C2 counter-parts. Clearly the AWD system provides some benefits. FYI - when I was testing my new clutch engagement on jack stands the front wheels began turning immediately. Maybe in some of the earlier videos their AWD system was worn and not functioning properly.
Anyone live somewhere snowy and wet with a C4 or 4S? Care to take a video and see if the front tires will engage?
Can a mod split this thread into its own new topic?