code.monkey

I'm thinking of upgrading the ECU chip for my 1990 964 C2. It has the RS single-mass flywheel fitted, and so is prone to stalling sometimes. I'm hoping to get a chip that will correct this as well as give a modest power increase.

Can anyone recommend a good make of chip?

Is it just a matter of fitting the new chip and you're good to go, or is further tuning usually required?

Thanks!
Sam

C4-JohnO

Hi Samuel

I can't help with the chip question but welcome to Rennlist and lets see a pic of your car!

Computamedic

If it were that easy I'm sure everyone would have done it by now. Firstly, your profile doesn't give any clues regarding your whereabouts - so issues such as fuel availability, altitude, temperature etc. etc. are unknowns. All of these factors will have an influence on any modification to the ECU chip.

Any of the "standard" off-the-shelf chips will be based on a standard set of parameters which may, or may not, suit your requirements or situation. Most will assume access to better than standard fuel and many will increase the rev limiter (or remove it completely). Few will give you what they promise and some will leave you worse than when you started.

Maybe you're beginning to see why it's not a simple answer.

The BEST solution is to have the ECU dynamically mapped on a rolling road to ensure the timing and Air/Fuel Ratio are correct for the fuel you want to use and whatever other modifications your car already may have. There are a number of places in the UK who will do this - you will need to find a local shop with the capability. The downside is that this is MUCH more expensive than buying an off-the-shelf chip.

Personally, I have a ProMAX chip (www.promax.uku.co.uk) which has been designed for the UK market using 98RON fuel. I also have a K&N air filter and a Fabspeed free flow exhaust and I am happy with the end result. Others will have differing opinions without doubt.

Hope that helps.

Regards

Dave

code.monkey

Thanks for your reply! As for my whereabouts, I'm based in Vancouver (British Columbia) in Canada. The highest octane fuel I've seen commonly available is 94 (which I guess is around 98RON). Oh, I also forgot to mention, I have a K&N cone air filter installed.

Hmm, the more feedback I get, the more it sounds like an off-the-shelf chip just isn't worth it...

chancecasey

It really isn't worth it if it isn't custom. FYI you can get a completely custom chip for $500 but you have to supply dyno/AR data to tweak it just right. You would also ideally like some real-time ecu output to make sure you aren't detonating / retarding spark timing, presumably the benifit of that data as supplied by the UK vendor mentioned above. I can get either of those data on my car for less than $100 each - I'm actually trying to find a shop that will do both simultaneously. Then for a whopping total of less than $700US I/you could potentially see a much better power response - or, very possibly not one at all. The odds are probably in your favor since you're on 93 or 94 octane - I think it's worth the gamble if you can get both dyno/AR and realtime ecu data. If you can't get a shop with both, buy your local private shop guy with a Bosch Hammer a nice 12-pack or something and get him to meet you at the dyno place. www.dynojet.com lists shops with their dyno producs as a starting point.

dougn

i'm in the middle of chipping my car right now. i have a stock ECU dyno (in san jose dynojet 248) and a post chipped dyno measurement that shows almost no difference (slight increase from 4000 to 4500 rpms). its a steve wong chip level one custom deal where i measure the A/F and report to him so he can tweek as necessary. well the A/F was very good at slightly greater than 13 but the car doesn't make any more power. he advanced the timing some 3 degrees i believe.

we're puzzled as to why there's no power increase. one thought is knock sensors are causing the timing to retard although you can't detect pinging by ear. i was going to try some race gas to see what effect that has.

it's definately a science project.

BTW my car has about 60k miles has a cone intake and GHL headers. it puts out 235 RWHP and 222 ft lbs peak torque

Red rooster

Dougn,
The most likely explanation is that they are modifying the wrong map set .
If you change stuff the ECU isnt using then nothing happens !!

The RS is a pretty basic remap and gets + 10 bhp.

Good luck

Geoff

dougn

that's interesting...the F/A did change however. yeah i thought about the RS thing also. how many ignition maps are in there?

Red rooster

Quite a few idle/part load/full load . Same for fuel . The combination is selected by coding.
Best approach is to run an in circuit emulator to check on the set being used.
I have seen this error quite a few times.

Its the usual reason for "chipping doesnt work " !!!!!

As a guide a properly mapped 964 should get to a bit over 270 bhp.
A 993 non vario has used up this de-tune to get its 272 bhp.

Good luck

Geoff

dougn

i'll talk to steve about it...thanks. from what i can tell the 235 measured RWHP equates to about 270 at the crank. interestingly....a stock boxster s is good for about 220 RWHP on the same dyno....for a reference point

Lorenfb

"a post chipped dyno measurement that shows almost no difference (slight increase from 4000 to 4500 rpms)."

What did you expect? It's basically a waste of money especially on a knock sensor
car. Read the many posts here on Rennlist and also read this link:

www.andial.com on the FAQ page Question #2.

Hope you're aware that with a stock engine the only real re-map
which is done is a "pushed" ignition timing advance re-map.
This usually results in pinging or requires an increased octane.

Bottom line: Don't waste your money or spend it on a useful mod,
e.g. the suspension.

Note:

"what i can tell the 235 measured RWHP equates to about 270 at the crank"

Making a comparison to crank measured numbers is ridiculous
unless you pull the engine and then put it on crank dyno!
Plus, you also MUST have the same TOTAL setup as the original
test case, e.g. the Porsche dyno test plan.

dougn

i have read them.

you're telling me Porsche optimized the A/F and timing so that maximum power is produced. any more advance would cause detonation and possible engine damage?

i'm betting they were a little conservative with both power and emissions so that some one in arizona in the summer time decides to overheat and overload the engine it wont be catastrophic

Lorenfb

"you're telling me Porsche optimized the A/F and timing so that maximum power is produced."

And why not? Sounds like someone's been reading too much marketing hype.
Read the many many many posts on Rennlist about performance chips.
Porsche/Bosch didn't leave some "easter eggs" there in the DME ECMs as
some might imply to be harvested for additional max power.

"i'm betting they were a little conservative with both power and emissions so that some one in arizona in the summer time decides to overheat and overload the engine it wont be catastrophic"

Heard this one too! Probably from the same B.S. chip guy you did.

*

Steve Weiner-Rennsport Systems

Doug:

There are a lot of variables in chip tuning and not everyone gets this right. The grade of fuel used on the 3.6's makes a very big difference if a performance chip is used.

Indeed, Porsche has to tune these cars for the lowest possible denominator (some South American fuels) and worst conditions (Arizona and the Southwest). A properly made chip that is tuned for the gasolines you will use will make a measureable & noticable difference.

There is an interesting dialogue to read here: http://forums.pelicanparts.com/showt...hreadid=260911

Lorenfb

"There is an interesting dialogue to read here: http://forums.pelicanparts.com/show...threadid=260911"

Excellent suggestion! Read how many fail to understand engine
dynamics, even those that try to write about it.

The ones that promote the chips in a positive way are those that usually have
an interest in selling them. This thread is another example where the chip made
little or no difference. You've answered your own questions by the results you obtained.
Again, read the Rennlist threads. They ALL have the same results.

"Indeed, Porsche has to tune these cars for the lowest possible denominator (some South American fuels) and worst conditions (Arizona and the Southwest)."

Wrong! That's why these later cars have knock sensors to basically
run at max timing and adjust for various engine loads, temp, and
octane levels.