How to tell if a Performance Chip has been installed
 

Hey everyone,

I am unsure if the previous owner had installed a performance chip in my 944. I know that he had considered doing it but am not sure if he has done it for sure. Unfortunately I am no longer in contact with the previous owner so I am curious to know if there is any way to tell if an aftermarket chip has been installed in the DME? I'm guessing the manufacturer would probably install some kind of sticker on the chip itself (I haven't looked yet). Are there certain chip numbers that I can look for or is it just going to be some generic EPROM and there's no way of telling unless it is labeled otherwise?

Thanks.

Probably the easiest way is to rev in 1st gear and see where the fuel cutoff is. Stock is right around 6500, I believe. Most aftermarket chips raise the rev limiter to at least 6750 or so. This is especially true on 944s as this will allow you to get to 60MPH in 2nd gear and vastly improve the 0-60 time.

You could pull the computer unit and physically look at the chip. It takes about a half an hour round trip.

I don't know about about early models, but I'm pretty sure late ones top out at 7K, with a stock chip. Aftermarket should go above that. If sticker on chip has only printed numbers on it, it is most likely stock.

My stock chip hit the rev limit around 6600 on the tach. My performance chip has a 7000 rpm rev limit, but the tach reads a bit over where 7000 would be when it hits the limit, so maybe my tach is off.

My 87 924S went to 7K with stock chip, and goes to 7.5K with a weltmeister chip. Not sure if it's your tach or not though. There WERE some differences in that model year. For example, mine has the low oil level sensor, but I know that some do NOT have it.

Another indication would be poor gas milage. If everything else is in order, a N/A 944 should get 28 MPG highway with no performance chip. Same for a 944S. A turbo 944 MPGs is much lower though. I'm having difficulty getting more than 20 MPG highway. My 924S is chipped but I don't drive it on the streets. It's definitely burning through some premium fuel on the autocross course. Of course I've either got the gas peddle on the floor or I'm standing on the brakes! http://forums.pelicanparts.com/suppo...eys/icon26.gif

Stock rev limits:

The 951 rev-limit is 6480.
Early 944 is also 6480.

The 924S is 6640.
The late 944 should also be 6640.


-Rogue

Best advice so far.

Not only will you know if it has been chipped, then you will also know which chip it is.

Yep,

Open it, look at it and while you are there run over it with a soldering iron. Cured many little issues with my car this way years back.

Apparently, it is MY 924S tach that is off, then.

Most of the 944 that I've been in the tach is off.


-Rogue

I'm not a believer that performance chips will lower your fuel economy, if you are light on the pedal. I have no problem getting 25+ mpg on the highway (at 75mph) with my 951S. And I know that my fuel injectors are not particularly well matched. When I finally get around to testing the flow of all 9 of the injectors that I have, and install the 4 most closely matched ones, I expect my fuel economy to get even better.

If you are using a 3bar FPR, with chips that are designed for 2.5bar, I imagine that would reduce your fuel economy. A clogged/melted catalyst, bad/fouled O2 sensor, or numerous other things could also be the reason your fuel economy is that bad. Not to mention, a lead foot would also be a contributory factor.

Oh, there IS one other thing - tires. My fuel economy does seem to be lower when I'm running the stock size bridgestone potenza performance tires (and 7/9 inch wheels), which is typically may through october. From november through april, I run a set of 205/60-16 firestone winterforce directional tires on 6/7 inch boxter wheels. Even with gearing being taller due to the larger diameter of the 60-series tires (meaning that every mile measured by the odometer is actually longer), my mpg is higher than it is with the wider performance tires. And I don't feel (or hear) the roughness of the pavement surface like I do with the hard-compound performance tires. At temperatures below 40 degrees (F), performance tires loose any advantage that they have over "standard" tires, anyways. Well, it's time I'm outta here.

my 951 gets about 27mpg usually- mostly stock, only a 3 inch exhaust and boost enhancer and my previous car(1987 944s) got 28mpg with a LR chip. its all about your foot!

Supposedly the 944MAX chip has been tuned well so that it doesn't run excessively rich. I didn't notice any drop in fuel milage, and that was with running a cat on FQS set to normal. The chip was tuned with no cat, so I was running rich. It'll probably get a tad better mileage set lean with a cat, and get more power for the same mileage without. I will find both out as soon as I get my motor broken in.