"This is Alex's '95 3.6 before and after a uni chip application."
The chip mod fixed the "holes", which were the problems, as Craig VERY accurately points out.
The key, though, is that little overall gain resulted, with any performance chip.
I agree that some tweaking MAY be required for unique engine mods, but very little.
This is usually with regard to the AFR (ideal @ 12.6, see my web site (
www.systemsc.com
on Graphs page). (12.6 = 14.7 (Lambda=1) X .86) That's why most/all chip suppliers have
one version. Having multiple versions is a marketing gimmick.
Andial's mention of an AFM=14 was based on the ideal ratio for complete combustion.
As can be seen from the graphs, the torque is fairlly flat from 11.5 to 14 AFRs.
The timing usually is not affected by most mods with the exception of compression ratio,
e.g. Ralph's per his thread had to be retarded a little.
Given the above, that's probably why Andial didn't put a lot of effort into chip mods on their
conversions. The required small tweaking can easily be accomplished by adjusting the AFM or the
fuel pressure on the 3.2 or the 3.6 (964). Remember, 3.2 to 3.5 is less than a 10% change.
How much additional fuel is really required for the additional air? The AFM will compensate anyway,
until the AFM maxs near WOT.
Again, little can be gained with chip mods. Porsche did it's job right.
If you want to "push" the timing and always worry about pinging and
finding the right octane, then a little gain can result.