Those of you with chiptuning - I've got questions!!!

I'm a bit skeptical towards chip tuning my Euro 1984 Carrera 3.2 no cat. First of all the car has 142000 km on it which means it's a bit worn. Second I find it hard to believe that simply replacing the ECU can give 10 to 15 extra horsies plus some extra Nm of torque.

Therefore I would like to hear your experiences with chiptuning a 3.2 Especially if you happen to own a EURO 3.2 like mine. US models might react differently to chiptuning?

How does your car behave after the chiptuning? Still reliable and with steady idling? Does it have better torque, mid range/low range pull? Does it feel faster? What about fuel economy? If you don't use the extra power will it then remain the same?

Please share your opinions and experiences.

Mikkel, I have an Autothority chip in my 89 3.2. A couple thoughts: It is a relatively cheap upgrade, I got mine on Ebay for $200. The installation is painless. The chip is based on a principle of recalibrating the Motronics to run on higher octane fuel. I always use the highest I can find, 92-94, so that wasn't a problem. I could get expensive I would imagine in Europe. As far as fuel consumption, my thoughts are that is uses more fuel compared to before. The power increase is hard to compare without actually putting the car on a dyno. The redline is bumped up to about 7000. If you take the car to the track, this is nice, but 3.2 to take kindly to overeving for extended periods of time. The reason I ended up getting a chip was the information given in Bruce Anderson's Performace Handbook:

" Emmision requirements are only applicable to engine manufacturers under normal driving conditions, and they are allowed to disregard them entirely when the cars are driven under wide open throttle. Consequently, wide open throttle is where the chip makers make most of their changes. Some makers have altered some of the part-throttle maps for some improved driveability, but the real performance gains are at wide open throttle.
A few years abo Jerry Woods and I did some testing of all of the chips that we could get or hands on. We tested Authothority, Hypertech, Z industries, Keno and Knightech. At the time, each chip that we tested offered some improvements over the stock chip at some rpm range. The largest horsepower improvement that we saw was 9 percent, and at peak horsepower the greatest improvement was 4 percent, of an increase in power from 217 DIN hp to 226 DIN hp. The average improvement of the best was 3.4 percent. That is picking the best performance of the best chip for each given rpm of the test."

I would think a Euro car like yours would even benefit more from its better performance output.

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8 9 9 1 1, The last of the line.

I put an Autothority Chip in my '84 Carrera (US spec) with the 3.2 liter engine. I also have a K&N cone air filter, cat by-pass pipe, and a low restriction muffler.

The chip had a positive effect on the drivability of the car. I specifically noted the engine was stronger in the low and mid-range RPM's. Autothority provided me with a dyno graph that showed increased torque across the entire power curve. The chip also increased the max RPM's by 400 RPM to 6850.

I don't believe I got 15 extra HP, but the car is much more drivable. I have never actually dyno'ed my car, so I have no emperical data, just a "seat of the pants" feeling. All in all, I am satisfied with the Autothority chip.

Regards, Bruce

Without sounding like a complete neophyte..which I am..What is involved in installing a chip? Does one have to make other adjustments?

Larry,

I can only speak to the 84-89 3.2 liter Carreras. It involves disconnecting the battery and then removing the Motronic "brain box" from under the drivers seat. You open the Motronic box and carefully replace the OEM processor chip with an after-market chip. Very similiar to replacing a computer chip in a home computer. Finally, re-install the Motronic box and reconnect the battery.

Be advised that some of the 84 Carreras have their OEM chip soldered onto the mother board in Motronic box. Removing these chips is a little more difficult due to the solder.

Bruce

Hate to throw cold water on your parade, but some of you need to read the quote from Bruce Anderson VERY CAREFULLY, a couple of times! Now, be informed, all you are changing, is the fuel enrichment (timing of the injector pulses) and the ignition advance map (spark timing) and that in times of declining gasoline quality, what you are gaining is a very slight power increase, but reasonably risky, SINCE THE 3.2 engine DOESN'T HAVE A KNOCK SENSOR!!!

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Warren Hall
1973 911S Targa

[This message has been edited by Early_S_Man (edited 02-27-2001).]

Good point Warren. I run Sunoco 94 octane (readily available in my area) and have not experienced any engine knock problems.

Bruce

I have a '85 Carrera with the Weltmeister chip. I have noticed better acceleration in 2nd gear from around 3500 - 4k rpm on up. Not a whole lot better mind you. Meaning, I have not done any sort of testing. I would like to get the G-tech accelerating black box and see what it specifies. Then change the chip back and see what info I get.

My mileage went down about 1 MPG (was 26 MPG before chip and now about 25 MPG after chip). I make the same 400 mile trip to my parents on a 3 month basis.

I run 92 octane here. I have run 89 octane and I get pinging right around 4k on up in 2nd and 3rd gears. I won't get 89 octane again.

I thought the 86 - 89 Carrera's have KNOCK sensor?!?!! Hence, the higher compression ratios and the higher HP ratings in these years... I think I read that in Bruce Anderson's book.

Just my .02
Nick

To piggyback on what Warren mentioned, not only does the 3.2 not have a knock sensor, but I was specifically warned by a tuner in Portland, OR (Steve Weiner) who was going to map a chip for me that it is difficult to even hear when the 3.2 is knocking (except under heavy load). I just didn’t want to take the chance. It’s one thing to be driving a quiet water cooled engine, get a bad batch of gas, and know immediately that something’s wrong because you can hear constant pinging at all levels of acceleration/load (talking from personal experience). It’s another to never hear it and silently destroy my beloved 3.2 engine. So I decided I’ll be going with the SSI header / Dansk muffler set-up instead, and forego the chip.

Btw, my 84 was one of the first to roll of the line and has the soldered chip. Makes for a slightly higher chip installation cost.

The Weltmeister chip was mapped for minimum 91 octane which still provides some cushion if you run 92 to 94.

All very interesting points. I asked some german Porsche owners the same questions and got different kinds of answers. Most said that chips didn't help on hp or torque. Some said that chips were bad for engines with more than 100000 kms on them, and a few were happy with their chip tuned 911s.

The octane rating that's recommended for euro 3.2s is already 98 from factory so you can't really enhance on that, can you???

A SSi like exhaust is probably one of the best ways to gain power, but for me that's not an option - due to the noise legislation here in Denmark. That's why I'm curious about chip tuning.

Mikkel,

Just out of curiosity, do you happen to know what the noise limit on your car's model year is in dBA, and is there an exemption for older cars, say '74 or earlier, or maybe a higher limit?

The reason I ask is that putting a '74 exhaust on your car might raise the noise level, but it wouldn't raise it to '74 levels!



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Warren Hall
1973 911S Targa

Mikkel,

Is the 98 octane rating based on the US formula? I may be mistaken, but I was under the impression US and Europe were slightly different. If so, something else to consider since the Autothority, Weltmeister, etc. are based on the US formula. Could someone quickly educate me here? Thanks.

Mikkel,
Keep in mind that the '84 euro 3.2 is already tuned to a higher level than US spec(231 vs ~207). I doubt that a simple chip would do any more for you. The only weak link in your setup is the exhaust. A tuned equal length exhaust system like SSI or FVD is the direction you should be going. Another possibility for high end power at the expense of the bottom end would be 964 cams.