I had a friend of mine who has an auto shop who just built a 383 stroker for a C5.
The car owner had a Ed Wright do a custom PCM tune and being it was not a good tune the owner required Wright to take out a PCM lock this tuner puts into peoples own property and I find pretty low to lock a owner out of their own PCM,

Owner gets this unlocked tune and shop owner brings car over for me to just put the Ease scanner on and see how engine is running.
Engine also has the larger SVO 30 injectors so I was floored to see the fuel trims at +25% LEAN while at idle.

Shop owner asked if I would tune the PCM being there was no way even he would drive the car that lean to burn pistons.

I downloaded this wright flash and began looking at the tables and again was floored !

Looking at fan setting I found highstage fan set to 1,022 degrees !

Injector flow tables look like this :



Being it has larger injectors and so lean at idle, notice that at high engine load the injectors were set to go twice as lean,
IMHO, this during PE or WOT would have melted down the pistons.

Then looked at high octane tables which is when there is no knock occuring and found this:



As you notice, starting around 0.6X grams/cyc the timing was reduced to around only 16 degrees when it should have been around 28 degrees but the timing at idle was 29 degrees when it should be around 18 degrees !

Throughout the flash tune I found this type of highly suspect values and can only wonder why a PCM tuner would not only do this but also not have even crosschecked all the values that were changed to see if they were valid.

I retuned the whole PCM calibration and now engine is running correctly which shows the flash was not corrupted by some other means, plus the car was running badly when shop owner came to me saying the PCM was functional.

I grade this product/service a F minus

If you notice the above post was 5 years ago back in 2003.

We have seen many more bad tunes from this vendor since then but the following one we just finished debugging and cleaning up one of the worst tunes we have seen yet from that vendor.

Our viewpoints come not from being bias but from the facts of the car owners, the conditions seen with poor running powertrains but from the PCMs own reporting via OBD realtime data and the tuners own work found in the PCM

Much of that can be seen in the snapshots shown below.

In this case the 1998 C5 owner had a shop build a all out race engine. They stripped everything they could to reduce weight including the BCM, even stock wiring harness to reduce the weight and then build a custom wiring harness.

Keep in mind the engine was designed by the builder for 650 N/A flywheel HP but still using the slower less tuneable 1998 PCM and mantained the small stock 75 mm MAF.

In part they decided on using the 90 mm LS7 throttlebody and using that POS FAST intake manifold and also those over priced LG Motorsports headers where for some reason they heat wrapped the headers.

After engine build they could not get engine to run using a Katech tune.
They then contacted Ed Wright who does blind tunes in he has them mail him just the PCM. He works with ZERO scanner data thus is in total blind of the makeup of the engine design nor even knows if the mods work together nor is there any problems that should be resolved FIRST.
He cannot since he has no hands on to the car or any OBD data to determine if everything is working or would see faults that need to be corrected before a valid tune can be done.

Customer pays for the tune and shipping of the PCM.
Has to wait until PCM finally returns, installs it and engine still will not run !

Wright tells owner the PCM must be BAD and owner has to buy another PCM and pay again for wright to tune that.

We had the owner send us both PCMs to find out 1st PCM was not faulty but wright forgot to turn VATS off knowing the car was totally stripped down for race weight and had no BCM for VATs to function.

2nd PCM allowed engine to run but after just a few races the $30,000 plus spent on this race engine blows up.
Owner has to pay for a total rebuild, including a broken crank.

Has to pay builder for this but owner suspects something is not correct and contacts us.
He buys a OBD scanner from us, we remotely teach him how to setup, use and do scanner recordings to email to us.

We have him do JUST a idle scanner recording and in analyzing that we suspect the tune was set to that PSO speed density and that PCM was help to OPEN loop only

We find, when at idle ( which the tune was set to about 1,500 RPMs !) that PCM is reporting fuel trim cell 22 (WOT) when it should have been idle cell 19

Vaccum was low, while MAP was high, Long term fuel trims reporting +25% lean and short trim at +50% lean for bith heads !
Front O2s sensors are flat lined, staying around 230 mVolts.

That is when C5 owner sends us the PCMs to download both flashes which we compared to a totally stock 1998 GM calibration.

We find in part.

To mask the problems and kept owner in the blind most DTC error codes were turned OFF !

PCM was commanded to stay in OPEN loop till water temp was over 150 deg C which is never !

Knock, misfire and torque management ALL turned off !

What this was then was tuning over the real problem which allowed the engine to function, ignore the MAF and front O2s till the engine got wacked in short timeframe.

The real problem we found was

1998 PCM still used which has limits over 1999 and newer PCMs.

Used stock 75 mm MAF but then used a LS7 90 mm throttlebody with a POS FAST intake manifold with a engine design problem.

Heads of valleypan bolts were hitting the bottom of FAST even before it is bolted down.
Then with intake bolts are installed it pushed the bottom of intake on top of valleypan head of bolts this distorted the bottom of intake but still did not allow the intake rubber gaskets to seal to valleypan thus most ports had leaks causing high lean condiions and why engine would not idle at nomral RPM levels.

None of this would have happened IF the tune was done correctly and they had NOT turned off most of the DTC error codes as then engine would not have functioned but no engine damage would have occured forcing engine builder and tuner to correct their problems.

Examples of what GM stock values are for a 1998 C5 are shown on left side of PCM tables shown below and then the values wright used. Notice the function of the table shown in blue of the wright tables shown to the left of stock GM tables.

Also in debugging we found the POS LG Motorsports LT headers with cracked welds that allowed even more air to be sucked in close to the front O2s and a high output ALT was installed which upped the voltage to 15.5 volts when the stock 1998 PCM was designed for no more then 14.5 volts thus causing PCM to fault on high voltage trigger window which also effects how electronics function including the fuel injectors

Closely look at the OBD trapped data, few of the tuning tables and the flaw using the FAST intake.

1998 Racer Fucked up with Crap products and tune