Here is my latest creation: A custom diagnostics port based on a LEMO 7-pin connector installed into an early 993 DME. The engine is installed in a 74 coupe. With the diagnostics port I can hook up my Hammer or PST2 to check the DME just like on a normal 993. This port came in very handy for the second task: Validating a chip with different map settings.



I installed a dual-chip for this car. Both map sets have fixes to prevent the engine from stalling with its light-weight flywheel. The standard map settings assume 91 octane pump gas while the track setting can take full advantage of higher octane race gas.

The Porsche diagnostics testers have a function to count the number of knocks during a test drive cycle. During spirited test-driving with the engine hot and using pump gas we observed 5 knocks during 10.000 ignition events on the stock setting and 55 knocks during 10.000 ignition events on the performance setting. This nicely demonstrates a couple of things:

- the timing retard nicely keeps knocks in check even with gas that is not meeting requirements
- mild chipping does result in performance gains that can be fully realized with higher octane gas available at the track

Since the only difference between the two chips are the map contents switching can be done while the engine is running. So if you need the extra power you simply reach under the drivers seat and flip the switch while there is not reason to worry during every-day driving.

Cheers,
Ingo

 

Very Nice! For your next trick, design a plug and play - dual chip setup for the 993 so we can take advantage it !!! I'll even be the first to chime in on the discounted group buy for Rennlist members!

 

WOW! If you ever decide to make this commercially available, you'll have some takers. Can you tell us a little about how you programmed your chips? AFAIK there's only one person who can program a Motronic chip... you'd be person #2.

A lot of us would love to hear your fix for the LWFW stalling, but it sounds like you may be keeping that to yourself. I hope I'm wrong. You'd be the first to solve that.

 

The real trick would be a set-up for the '96 993's with ,IIRC, the soldered in chip ! Hint Hint !!!

 

"A lot of us would love to hear your fix for the LWFW stalling"

This has been done previously by a Rennlist member (Jason A) and mostly likely copied
by many. Just do a Rennlist search.

"So if you need the extra power you simply reach under the drivers seat and flip
the switch while there is not reason to worry during every-day driving."

Extra Power? - As most 993 owners now know, i.e. as has been posted here on Rennlist,
very marginal at best results are obtained from "pushing" the timing ("performance" chips) on the 993.

"AFAIK there's only one person who can program a Motronic chip... you'd be person #2."

Hardly! There are MANY out there, which has been the case for over 10 years.

 

I know he considered it, but AFAIK it never materialized. I think he was considering fooling the ECU into thinking the heater was running or maybe he had other ideas.

I'm obviously referring to CUSTOM tuning, not the big guys like GIAC etc. Let's say I want a race-fuel map, or to supercharge/turbocharge my car with the factory ecu. If you know anyone who can custom write a chip, I'm all ears.

 

Very nifty solution but I HATE Lemo's Autosport connectors, all the way

 

"it never materialized"

Actually, Jason was providing chips to those that were Rennlist members
and emailed him.

"I'm obviously referring to CUSTOM tuning,"

Right! There're WIN apps out there that will EASILY do that.
It's hardly difficult for those that have basic knowledge of engine theory
and PC software/hardware, e.g. EPROM programmers/emulators.
Those who promote/comment/sell on Porsche websites give the impression
that "performance" chip tweaking is some super-exotic-highly-technical
special science, i.e. a real joke. You could easily train a H.S. auto shop
student to do it in a couple of hours.

"If you know anyone who can custom write a chip"

It's far from "writing" a chip in the true technical aspect, it's just
a very simple matter of changing cell values in a matrix which
takes a minute or two. The time consuming part is the evaluation
of the change which, again, any H.S. auto shop student can easily
be taught to do, once the output data (torque/AFR) are targeted.

 

Loren, since you are one of "...Those who promote/comment/sell on Porsche websites..." are you saying your skills are that of "...any H.S. auto shop student..."

BTW, aren't you selling performance chips...?