Bill Verburg

Th flange on the passenger bank 993 header was rotated 90 from all previous models in addition the heater connections are very different. The exhaust is therefore unusable(without non trivial mods) on earlier cars. Compare the following 2 pics, the upper is a 964 exhaust the lowr is a 993.

Randall G.

Hi Bill,

Thank you for the wonderful diagram. Helps me understand another reason why my mechanic encouraged installation of the 964 exhaust on my 993 engine.

Would you happen to have the parts list that goes with the diagrams? This would help me understand the exhaust/heat layout completely.

Thanks!!

Jerrygreene

Bill, also thanks for diagram. However, I am lead to belive that the 993 system can still be mounted to the 964. (In search of more power) Your statement (without non trivial mods) I think supports this. Flanges would have to be cut off, rotated, then rewelded My question has any one done this? If so, Would like to ask more questions.
Jerry Greene

Blackart

The Proverbial 1000 words...

Christer

Carrying on in the 'mods' mode, there is a hotfilm air sensor conversion available here in the UK (i'm sure its available in the US as well) which gives a VERY good gain in horsepower and torque. My friends C2 showed 247.5hp before the conversion and 284.2hp after! The conversion costs around £1400 plus tax - so around $2300. There is also a company called AMD who do a chip conversion followed by rolling road setup, and this does usually add 20-25hp depending on your original output. This costs around $500-600. I have not seen both these conversions done on one car, but would assume that the results are not completely accumulative - i.e. that you would get 310hp but it should be possible to get around 290-295hp. This does not necessitate any other changes to the engine - apparently it can handle the increases comfortably.

As I have not had the pleasure of driving my friends car, has anyone had experience of these particular conversions?

In any case, I will hopefully let you know when I have had them carried out on my car.

Jeff Curtis

Melissa! Good subject, if you're going to convert your rear calipers to four piston, as I recently have (have pics too) be sure and change your bias valve to a 35bar from a 45 bar as I am presently experiencing troubles on the track w/overheating the rears and causing the ABS to constantly intervene! I am currently touring the Midwest w/truck/trailer and Track Rocket, this will be my first change upon returning home.

Here's MY mods:

Carrera Cup Lightweight Flywheel and Sachs "Sport" disc and aluminum PP - (to answer GP964's question)

17" Boxster wheels for the street

H&R 965 Turbo lowering springs (more weight per corner)

Bilstein HD struts/shocks (no "SPORT" available)

Sebro cross-drilled rotors, never again, the hats rust like crazy after washing the car and going for a "spin cycle"...splattering orange stuff all over your wheels!

Four piston calipers off of a '93 964 (direct conversion - no mods necessary) - takes the same pads as the front, making it quite handy at the track, i.e. if your fronts are wearing fast but not the rear, swap all of them around the second day if you don't have extra pads.

Drilled airbox

Fabiani catalytic pipe and muffler, not installed as of yet.

Brey Kraus strut mount brace

Stainless steel (DOT approved) brake lines, ATE Blue brake fluid - changed out religiously via a POWER BLEEDER!

***Haven't really done any HP mods as I am still getting the "feel" of the car at the track***

Future upgrades:

Any HP mods

BIGGER sway bars

Lower bar bias valve for rear brakes

"Tom Sharpes" rear wing - yup, being that I have a GP White 964 like his, he says he is going to give it to me someday.

Bow Plane front spoiler, available through TRG

MadMarkie

Hi Melissa,

Mods so far on my black '93 RSA:

-Eibach Sport Springs, Bilstein HDs, TRG Adjustable Sway Bars (25.5mm front, 22mm rear), Weltmeister strut tower brace, corner balanced and lowered/aligned to Euro RS specs. Bridgestone SO2s (225f/255r) on the factory "Cup Design" wheels. It handles really well... and I can tweak the sway bars to stay entertained! Small price in ride quality (squish factor really, this car is NOT a Lincon... it's supposed to be stiff!)for a HUGE improvement on track.

-Autothority mass air system with EPROM and K&N cone, Fabspeed single outlet muffler to replace both factory muffs (cat still on), engine tray removed to improve cooling. I love the sound and feel of this setup... the car was purchased with secondary muff and cat bypass pipes, so I have played with most possible combinations. The cat bypass didn't change anything using the "Patagonia climbing shorts dyno" test, or stopwatch times between 3000rpm and redline in 3rd gear, so the cat stayed. The fabspeed helped a bit, and it sounds WAY better than the stock (also improves "girlfriend white-knuckle" test results with a wonderfull bass roar!). I haven't tried the factory air flow meter, filter, and chip, as it seems like too much trouble to (probably) decrease performance.

The car came with a nice Alpine sound system including lots of speakers, a big amp, and a 6 disc changer, but I almost always prefer the sound of the engine... addictive isn't it?

Planned mods (the short list... long list involves buying a second RSA, and converting the current one to a track-only sweetheart, plus a trailer and a new truck to pull it...):

-Fikse FM/10 wheels (2 sets, one with sticky rubber for track use, and one with SO2s for the street). Possibly Cup car wheels for the street; I love the Cup Design, but the width from the factory dosen't fill the flares quite well enough.
-Big Red Brakes... anyone have any info regarding these on the front only -vs- all around?!?
-993 Turbo S front brake ducts (with foglights)... sure look great!
-Cup car lightweight flywheel and clutch, when the current clutch dies.
-Euro RS engine and transaxle mounts.
-Last but not least($!), a 3.8l conversion with some serious exhaust improvements... like true equal length headers, but emmissions leagal (cats) to ease my guilty conscience, and perhaps a varioram intake conversion?

We were dreaming right?... seriously, I love this car, and plan to keep it (and modify it)forever!

Great thread, Mark.

Drew_K

Well I spoke with the local Porsche tuning guru, and I've decided to upgrade my 16 inch wheels to 17's and install Eibach Pro springs, including corner balancing.

Since the car will be lowered about an inch, are any modifications required to address bump steer?

Interestingly, I asked this guy about H&R springs and he said he absolutely didn't like them. He mentioned that their quality control has really fallen off and he doesn't trust them. I value his opinion since the bulk of his work is race prepping Porsches. Just wanted to pass that along. Don't shoot the messenger.

Drew
92 C2

Bill Gregory

Drew,

If you want the real thing, Porsche still has in the parts bin the M030/RSA springs, as well as the non-US 1992 Carrera RS springs (and Bilstein shocks). The Carrera RS springs are probably a bit stiffer than the Eibach's or H&R's. The Carrera RS was available in 3 versions - race, road, and touring (if I recall correctly). The springs/shocks available are those from the road/touring variety. Since you mentioned springs, the part numbers are 964.343.531.80 (code 504 yellow) in front and 964.333.531.80 (code 504 yellow) in the rear. List is around $425 for the set, but you can get them at discount for around $300. Any idea what upgrade I'm planning when I get my C2 - currently on the hunt...

J richard

Mark,
I've got the Autothority MFS on my 93 RSA as well, One question, Do you get a part throttle squeal from the intake? In my mind it sounds like a vacume leak during highway driving with light loads. I've heard from others with the same setup, some have the noise some don't. I thought it might have to do with the lack of under carpet sound proofing in the RSA's. Some actually like the sound.

Randall G.

Now Bill, why haven't you asked us for advice on what to look for in a 964 . You must think you know a few things about P-cars!

Bill Gregory

Randall,

Wait until I get the C2, then the questions will start flying!

Nick L

I'll throw in my $0.02 worth of very limited mods to my '93 911 C2 Coupe:

Windward K&N cone air filter - no perceptible "seat of pants" difference over stock

FabSpeed muffler (replaces both of the stock mufflers) - maybe a *slight* seat of pants difference in feel, but it's probably more due to the noise increase (it sure does sound much better - the FabSpeed makes it sound much nastier and stronger than it probably is)

Removed engine belly pan, for improved cooling - my car always ran cool before, and now runs a touch cooler at times (usually on long highway drives in hot weather), but overall little difference

Distributor ventilation kit - something we've probably all done

That's all I've done - I personally like my car so much the way it is, I've been reluctant to mess with it.

Thom Fitzpatrick

How about putting that engine into a lighter car

Jack667

Hi - new to this forum, I have been getting e-mails from Rennlist for the 964 list for a couple of years, but I have neglected this site. Anyway - Here are some mods that I have done for my 1990 C4 Cab:
- DAS Roll-Bar
- Simpson 5-point harnesses (with cam-lock)
- Fire-Extinguisher bracket (Brey-Kraus)
- Single-Mass flywheel
- K&N cone Air Filter
- Andial Chip
- Cat by-pass
- B&B dual outlet exhaust
- Perf Products left rear bumper piece for above
- 993 P&C ($520 ebay)
- Perf Products rear wing
- extra high 3rd brake light piece
- remove 3rd brake light
- replace with another LED light from JC Whitney of all places
- 993 Aero mirrors
- Boxter 17" take-offs from Wheel Enhancement (1 set for street, 1 set for track (Hoosiers))
- H&R CoilOvers (perf street, not race)
- negative camber dialed in
- Pagid Orange pads

Please feel free to ask about any of the upgrades. This is a great street car and it is also a blast on the track. It is sooooo fast. About 15 track days this year (DE) and every instructor is amazed with the power and how well it is set-up.
Check out my site at http://people.ne.mediaone.net/jbalthasar
includes many pictures and in-car video from NHIS, Watkins Glen, Mont Tremblant, and AutoCross.

I could go on and on about this stuff!!

Jack