Loren,

Not having been "handed" the answer to my question, what's a man to do but "LOOK"!?!?!?!?!?!?

I must ask for better definition of what you "noted",..such as: "better drivability",..(this needs definition,..not to mention quantification),....or/and ...."better O2 control",..(how so?),.....and, lastly,.."more responsiveness" (another begging question of """"HOW""""?)

Aside,..I must say that it's quite interesting to look at these threads from 8-9 years ago,..looking at the "writing",....then looking at some of the current posts,...more entertainment than enything else,....

As I like to deal with quantifiable FACTS...........

Proceed, sir..............;)

My best!

Doyle

Loren,

Thanks for your common-sensical reply.

Doyle

Just engaged the suggested url,..good read.

Doyle

The only difference between the early 2k 84-86 programs, and the later 28 pin programs is a slight increase in part throttle ignition timing and some additional part throttle fuel enrichment in the 0 to 30% low load areas between 1500-3000 rpms, giving the feel of a little more throttle response when you drive at low rpms. But whoopee, that's only 20% of the gains compared to a real performance reprogram; there's no power difference anywhere else as I've detailed above. If you have a early 24 pin unit, just updating it to a 4k with a jumper and installing a 24 pin chip from an 87 does the same thing. There's no difference in power or programming between the 4k 24pin 87 chip, and the 8k 28 pin chip of a 88-89. The extra 4k of the 28 pin chip was utilized to eliminate the internal ROM of the onboard microcontroller and put it into the that section to consolidate all the Motronic units which are shared with other car models and ease manufacturing.

But if someone really want's to explore this, you can do it yourself, or send it to me if you want. I've done it for guys who have requested it for $80. To do it yourself, change the socket to a 28 pin socket or add four additional socket pins where the four are missing. Mod the DME to 4k with the jumper mod if you need it, and solder a jumper at B700 to defeat the onboard microcontroller ROM and stick in a stock 28 pin 87-89 chip.

How much of an increase in the "part-throttle" ignition map (in degrees?).

Thanks, Steve.

Doyle

I'm sorry,..I just noticed your comment """"There's no difference in power or programming between the 4k 24pin 87 chip, and the 8k 28 pin chip of a 88-89.""""" Still I would ask of this "timing" advance, moving to the '87 chip...

Thanks,

Doyle

It varies but it's not significant. Anywhere between 4 to 8 degrees. The ignition timing is kept low to keep NOx as low as possible. Some additional fuel enrichment on throttle transients is what is the true reason for the increase in low rpm throttle response, because the stoichiometric ratio of 14.7:1 is not optimal for power. The O2 sensor controls it to that because that is the ratio the cat is most efficient at processing HC, CO, and NOx. The 84-86 2k programming had a tight control on the mixture loop, locking it at 14.7 no matter what you did. This makes for a lot of sluggishness and delay in response. Unplugging it is what some of the guys did in the old days to release some of this lock and feel more response. The 4k programming from 87 up relaxed this lock and allowed additional fuel enrichment for a few moments when you gus it at part throttle, reducing some of this lag. But stock programming, 84 or 89, still has a lot of sluggishness and delay below 4000 rpm at part throttle. If you want to get rid of it you need to change the programming.

Proper part throttle fuel enrichment and ignition advance is what significantly improves this. You always need more ignition advance at part throttle compared to full throttle, because the fuel molecules at light loads are much farther apart vs at full load, so the speed of combustion is much slower. You need to ignite the burn earlier in order to achieve the peak pressure of the combustion during the stroke at the proper angle after the piston's top dead center in order for the stroke to achieve peak torque. Like packing gunpower tight in dynamite causes a rapid explosion vs loosely fluffed powder tossed in the air which would flash slowly.

As an analogy, compare it to pushing down on a pedal of a bicycle. By pressing down on the pedal at 1:00, you will develop more torque at the rear wheels, vs waiting until 3:00 to press down. Obviously if you press down at 12:00 that is too early and you will only hammer your knees. So timing this right and using a dyno to measure the changes in torque under load is how you want to properly determine the limits.

More ignition advance done properly is what achieves this. The general rule of thumb is that you want roughly 15 degrees more advance at light load part throttle compared to full throttle to accommodate for the slower burn of light throttle. This not only increases the response, but increases the fuel efficiency of the motor. Rarely does ignition advance at low and mid load part throttle cause an issue or damage engines unless done improperly. The combustion pressures are not high enough. If one examines the amount of part throttle ignition advance used by the 964 European Cup cars which their twin plug ignitions which further speeds the burn, you will see the factory used an extreme amount of part throttle ignition advance to improve throttle response, more than I've ever used, because they have no considerations for emissions compliance. So my recommendation is if you need to smog in a stringent state such as California which is reducing the limits each year, swap back to the stock chip temporarily and get it over with.

I will tell you this, there are a lot of championship and podium winning 3.2 and 3.6 race cars out there running my chips pounding their motors out at full throttle two hours a day, 20 to 30 days a year, for years, from 4000 to 7000 rpms with, either on 91 octane pump gas or race fuel, and if the motor ever comes apart, the pistons, rings, heads, and bearings are all flawless. If these cars can survive, don't you think a street car spending 90% of it's life at part throttle at low and mid rpms could do the same?

So really, you're not even exploring a built-in margin. You're taking a *purposely-detuned* program (for emissions purposes) and re-tuning it to eliminate the emissions-related detuning.

Is that about right?

"The only difference between the early 2k 84-86 programs, and the later 28 pin programs is a slight increase in part throttle ignition timing and some additional part throttle fuel enrichment in the 0 to 30% low load areas between 1500-3000 rpms, giving the feel of a little more throttle response when you drive at low rpms."

Oh, so there is a difference! So the previous comment that there was no difference
was incorrect. Then this can be stated and accepted:

1. Porsche had a reason for going to the larger chip.
2. There would be an improvement as stated previously in the overall running
and driveability.
3. That most would feel the seat-of-the-pants improvement just like with those
so-called 'performance' chips where many claim the same.

"there are a lot of championship and podium winning 3.2 and 3.6 race cars out there running my chips"

It's all the chips and the driver didn't even need to take a DE class, right?

"So really, you're not even exploring a built-in margin. You're taking a *purposely-detuned* program (for emissions purposes) and re-tuning it to eliminate the emissions-related detuning."

Total B.S. And what do think he'd say? No tuner is going to admit that.
There's always another one to get sucked-in!

There is a margin built in again knock for the octane of the fuel used. Otherwise you would just hear about issues and complaints such as knocking or whatever, of which you won't find any. They are not tuned for the purposes of meeting emissions, although many owners pass emission fine if you do a search.


Like I said, if you call going from a 1 to a 2 on the performance scale a significant improvement, vs a 10 on doing it with a rechip, then go for it if that's good enough for you. I think the thousands of 87-89 owners who have rechipped their car would disagree with you. I think the more interesting issue is that you are finally admitting there are performance gains to be achieved by rechipping a car, after all these years of denial, but then as it seems like you are trying to sell this as a service, I am not surprised.

"The only difference between the early 2k 84-86 programs, and the later 28 pin programs is a slight increase in part throttle ignition timing and some additional part throttle fuel enrichment in the 0 to 30% low load areas between 1500-3000 rpms, giving the feel of a little more throttle response when you drive at low rpms."

And those were only minor changes that could have been done in 5 minutes without
switching to a more costly memory. Additionally, algorithms within the control programs
were changed which required the larger memory.

Again on the issue of excessive 'pushed' timing, even the limited production 3.2 Club
Sport did not change the timing beyond the '88/'89 even though engine mods were
made to enhance the engine for the greater red-line. With this model because of
its orientation for racing, no real concern was about emissions which negates the
argument about two ignition timing margins, i.e. one for emissions, and one for
pinging/detonation. Besides, the 3.2 had a provision for reduced emissions,
i.e. the jumper wire near the ECM box which was connected for California cars and
Japan imports that retards the timing.

Those changes were already done in 1987 in the 24 pin chip programming. It was not about memory prices which by 1988 dropped enough vs 1983 to be insignificant. The slight additional cost of the 28 pin chip was clearly offset by the cost reduction in consolidating all the Motronic units that needed to be produced for all the different cars it was used in.

The US version Clubsport was a very limited car, only about 28 produced for the the US and still was a street car that required USA emissions compliance. It was not a 'race car' exempt from emissions. So your statement has no point.

Steve,

We all (or at least the vast majority of us) know that your efforts have demonstrably helped the performance of our cars.

It is, perhaps, pointless to continue a discussion with someone who has a vested interest in casting aspersions on your products, and does it using information of questionable applicability.

"The US version Clubsport was a very limited car, only about 28 produced for the the US and still was a street car that required USA emissions compliance. It was not a 'race car' exempt from emissions."

But there was less concern about emissions with the Club Sport, since it didn't have a retard
jumper wire. So they could have advanced the timing more but decided that the margin
of safety from detonation, especially in racing, was necessary.

"It was not about memory prices which by 1988 dropped enough vs 1983 to be insignificant."

Please, more B.S.! The logic is totally inapplicable as to why the larger memory.
Must have failed your logic class at USC, but again a music major doesn't require
a logic class, right?

"The slight additional cost of the 28 pin chip was clearly offset by the cost reduction in consolidating all the Motronic units that needed to be produced for all the different cars it was used in."

More that got pulled out of you know where! All the different cars that used Bosch Motronic
had minor circuit board changes, even the 944 that was closest to the 911 3.2 DME ECM.
So that negates some more B.S., i.e. they weren't consolidated.

"does it using information of questionable applicability"

- dw1 -

Like what? And dw1 (hiding there), what's your knowledge other than taking your alternator
out to have it rebuilt, i.e. takes some great thought, right?

"Interestingly, it was a Paris-Rhone, not Bosch. I checked and so was the original unit."

Here you comment about your lack of knowledge about something as simple as an alternator,
but now you're commenting about chips which are just a little more complicated, right?

Was the club sport 3.2 different internally in comparison to a regular 3.2?

Music major? I don't know where you googled that information. I have two engineering degrees not that it matters.

I think this old thread where you criticized Innovate Motorsport’s LM-1 wideband O2 air/fuel instrument pretty much sums up your lack of knowledge. I mean come on, using a voltmeter and the vehicle’s stock narrowband O2 sensor for measuring air fuel ratios for tuning!?! You won't get any useful info past half an AFR point on either side of 14.7 – the thing is basically an on/off switch around 14.7! What is even more ridiculous, recommending the use of a 5 band gas analyzer! The 1 minute delay between a sampling and a reading will get you nowhere, and then what kind of data would you have? The dyno run would have been over 50 seconds ago! Almost everyone knows in tuning engines one needs air/fuel readings accurate to within 0.1 of an AFR delivered in an instant to correlate to the rpm and load point it is recorded at.

http://forums.pelicanparts.com/bmw-r1100s-r1200s-tech-forum/140206-data-acquisition-computer-group-buy-offer.html

I'd have to say, these are some of your more comical statements:

okay ...


Good luck with that.


haha, ok!

The only difference on the Clubsport engine was the use of sodium filled exhaust valves. The rest of the engine remained unchanged and makes and dynos the same power at a regular 3.2. The primary differences in performance came from the reduced weight of stripped chassis components.

"Was the club sport 3.2 different internally in comparison to a regular 3.2?"

Read the spec sheet. It's posted in this thread.

Read the post above yours. The question got answered already.

"The question got answered already."

Don't think so! You too needs to read the spec, there's more.