Ted6060

Hi,
I have an 88 928s4 and I have a straight pipe, headers from 928intl.com, Autothority performance chip and ultralight, recaro ultralight seats, stripped, no ac etc...
I need a high performance spark plug
What you recommend?
Thank you!!!!

Speedtoys

Use the recommended cheap factory copper plugs.

Also, dump the fake AA chips, they provide nothing.

You want this: http://siriuscyber.net/sharktuner/

Ted6060

I like the idea but looks a little complicated to tune it. Can the HP torque be increased? I don't have an O2 sensor...

Speedtoys

Why not?

How is the car expected to maintain safe fuel ratios?

Or...run right really at all?

IMHO, that's a -lot- of faith in the AA chips, that were known to be "not good" 15yrs ago.

What your goal...it's loud, you got that on the right path..

Speedtoys

Also note, that the WOT map, even AA's, requires knowing what the long term trim levels are in the base map.

Without O2 feedback, your ECUs cannot adjust around naturally degrading components, sensors, and seals.

Every time you turn off your car, the MAF is ever so slightly different, than it was before..and it never gets better.

FredR

Sounds as though your model is a non cat variant and relies on pre-determined static mapping. Nothing wrong with this but over time and about 60k miles the MAF bit by bit loses its calibration and can end up under reading the airflow by a few per cent which although not monstrous it is significant and will cause a small power loss. This can be crudely compensated for by tweaking the CO pot. Models exported to certain parts of the world were equipped with this system. You do not state your location or more importantly where your example was supplied to originally so the first thing you should do is check the coding plug to verify that you have something configured as it left the factory engine management wise.

Beyond that the Autothority chips seem to get a bad rap- whether they actually do anything [good or bad] I have no idea. If you are serious about getting the best out of your 928 then you need to get yourself a sharktuner or access to one and fit some PEMS into your computers so that with the help of a wideband O2 sensor you can tune your motor is real time. The other alternative is to contact John Speake directly [or one of his agents] and get yourself one of John's generic chipsets- apparently they work well and probably a better bet for those who are not too computer savvy or into tuning.

Johns website is http://JDSPorsche.com

SeanR