E36S50

Is is possible to get 300+HP from a 993 3.6 without extreme cost and/or forced induction? Does the end peak HP # differ much from a '95 motor compared to the '96> Varioram motors? I know there are many "tuners" who will claim their 993 pacakges make 300+HP with just an exhaust, software, etc but I have a hard time believing it is true! IMO, a 993 with an honest 300+HP should put down at least 260RWHP on a Dynojet. I'd love to hear feedback from owners who have successfully upgraded their cars.

Thanks

Rohan Nath

Short answer - don't believe them. Close ratio gears appears to be the best option to improve performance at a reasonable cost (other than forced induction). It does not increase HP just feels that way.

Long answer - search the archives. This topic has been covered often and in extensive detail.

graham_mitchell

E36S50, to answer your original question QuikStuf993 recorded a 26hp increase from a Unichip and FabSpeed Cup exhaust installation. I believe the Unichip is around $600 to instal. Of course you should do you own research but that seems worth looking into.

Next step up is Motec, which should give you 310-320, afaik, but it quite a lot more expensive.

Viken

Feel? A close ratio gearbox, at least one that's similar to mine, is a genuine performance enhancer. It makes the car accelerate a lot quicker in any gear up to and including 6th. If you have a US or '97-on ROW naturally aspirated 993 this side of an RS, this is the best bang for your buck. All other *add-on* pseudo performance products are hogwash.

E36S50

Does it make "just over 300hp" at the wheels or the crank?
Please don't take offence to this, as I have no idea what state of tune your car is in or what other mods you have, but I wouldn't be too thrilled with ~300crank HP out of a 3.8L! A friend of mine with a 964 RS has an RS Tuning 3.8L that makes a solid 50HP more than that and is 100% streetable and reliable. Not a flame, just a point of reference.

Regards

Rohan Nath

Viken,

I'm not debating that a close ratio gearbox is a genuine performance improvement. However, it does NOT increase peak horsepower to the best of my knowledge. As I understand it uses existing horsepower more efficiently.

Viken

Exactly!

laurence '97 C4S

"How do I get 300+HP from a 993?"

Quite easily, trade it in for a 996.

Greg Fishman

I am sure you can get 300hp from a 3.6 motor and it still be streetable,but it will not be a cheap process. A 3.8 kit may be a better way to go.

Hank Cohn

E36S50:

I’m not sure what your tolerance is for extreme cost, but all of the old tricks apply. Most of an engine’s power is in the heads and the cams. There are several cams available for the engine and some head work is possible. Unfortunately, there is a ceramic insert in the exhaust port making it difficult to modify the exhaust side, however, there is still easily 30+ HP to be gained by replacing cams, a little head work and, perhaps, bumping the compression a tad. You would, of course, need some dyno time and a good chip tuner to extract the maximum out of this configuration.

Exhaust systems on stock 993 engines don’t buy you much because the stock cams have very little overlap and fairly short duration leaving little for headers or other tuned exhaust systems to work with. The OEM 3.8l “Power Kit” is fairly expensive and without other work doesn’t buy you much in the way of HP although you do get a healthy bump in torque. One note about the OEM Power Kit is that it uses slip fit cylinders which are fine for the street, but may not be the ultimate solution for the track, although no one that I am aware of has had any problems with them. One note about using aftermarket engine controllers. The stock DME has some great maps for all kinds of load conditions. It would be a shame to loose all of that and extremely difficult to replicate.

Regarding the transmission, it is amazing the benefits that are actually gained with better gears. On a power track like Road Atlanta, it’s worth almost 2 seconds!

Hank

LAT

Get the ROW tranny, I put one in my 97 C4 Cab and WOW! when you get to third and fourth they pull like an extra 30 hp.

Technically your torque factor is improved by the amount of increase in gearing. "Torque factor" I describe as total gear ratio times torque at a given rpm. Therefore if your total ratio (final drive times gear ratio) improves by a given amount so does the corresponding output to the ground. The trick is to balance the gearing so that you are constant in drop between gears as possible to maximize the available power band. The ROW tranny was designed as a perfect match for our cars in most applications.

Can't recommend it enough.

Enjoy.

YellowC4S

Wouldn't a chip, exhaust and K&N filter do it?

Fishey

I went to euro gearing and LSD and a stage 2 clutch...
all I can say is 2nd gear has problems putting the power down and I get a hefty chirp in 3rd (only did this once I mean I had to it was just asking for it..)

Going to buy dad a exaust system for X-mas and Intake for B-day...(dads Bday is Jan 14th)

He is going to buy me Exaust for X-mas and Chip for B-day... (my Bday is Jan 13th)

We worked this out... See my mom wouldnt let us just buy them ourselfs so we worked out a nice deal.

Steve Weiner-Rennsport Systems

LOL,...Extreme cost is all relative but you will not get more than 325 HP from any streetable 993 3.6 without a six-butterfly intake, extensive head work, bigger valves, and pretty aggressive cams,....

Varioram doesn't in and of itself, give more power, it widens the torque curve a good deal.

Really good software and a streetable exhaust gives about 18-20 HP. Removing the cats and installing a good set of headers adds about 10-12 HP but to take advantage of that, the cams, rod bolts, valve springs, and retainers should be upgraded.

Remember, Porsche A.G. needed the above intake system, higher compression, 102mm P/C's, RSR cams and headers to make a real honest-to-God 350 HP. A 3.8 RSR motor is not very streetable at all,...

djmc

I think a TPC supercharger should do it about $6800