Review tune C5 Z06 P01

[C5Z06TwinTurb]

Ok fellas, I have heard about the itch you get after your first mod to your car but right now I wish I had never even scratched it. I bought this car for 12k with 38k miles on it. It had been sitting up for many years but after some tlc she ran like a scolded dog. It had twin $130 amazon turbos on it T04E 0.57 A/R 48.1 TRIM that pumped 14psi and would light the tires up in every gear from 3200rpms up to 5500rpms. Well I got beat in a race by 850hp camaro so i set out to reclaim victory. I installed VS Racing Twin 61/62 T3 Special Turbos 3" .82ar and called a tuner to dial it in. He told me I should go ahead and upgrade fuel system so I upgraded to id1050x and Racetronix T6 450E fuel kit with adjustable FPR at the rail. To make a long story short I am down a couple hundred horsepower and trying to get the tune in line. Im baffed at the loss in power. On the verge of trashing these VS turbs for the amazon specials.

.NewFuelSystem-sftp-disabled-changed-fuel-offset-volts-v2.hpt61.hpl

Adding more details.

2002 C5 Corvette Z06
408 Stroker Thompson Motors
P01 ECM
317 Heads
RPM Stage 3 transmission MT
Stock Intake
Intercooler 2.5" dual inlets 3.5" Outlet
Twin 61/62 T3 Special Turbos 3" .82ar Rear Mounted like STS system
3.5" exhaust hot side
2" cold side
4" k&N filters on each
tial 44m wastegate with 8 psi spring and manual boost controller
2bar Map sensor
id1050x injector dynamics
I dont know, it was in the car when purchased
no cats, kelly exhaust
block has 6.0 on it
Racetronix fuel pump 450E kit
PQY FPR 10 micron inline fuel filter at rail
Single outlet to oem fuel rail, return line back to tank
Kenny Bell BAP with 3psi switch
ProMeth injection at intake dual nozzles 5gph each with 3psi pressure switch
Pump Gas
AEM AFR gauge
SPA Designs Fuel/Boost Gauge
I have a Tial BOV but it isnt installed yet.
I also have a VS Racing 44mm Wastegate on the second turbo but I have the boost line removed and thinking about capping it.

[C5Z06TwinTurb]

[QUOTE=C5Z06TwinTurb;838149]Hey guys 02 C5 Z06 408 stroker, twin rear mounted turbos, cam, racetronix fuel kit & adjustable FPR, Kenny Bell BAP, meth injected at 3 psi boost. I just need to know if I am set up correctly to log and make adjustments to dial in the VE table and power enrichment. I appreciate the help.

NewFuelSystem-sftp-disabled-changed-fuel-offset-volts-v2.hpt


NewFuelSystem-flow-117-scale-ve-20percent-ve-changes1.hpt

76.hpl

25-07-06 16-18-28.hpl

VCM Editor.cfg

VCM Scanner.cfg

It feels like every time I make adjustments to the VE table I continue to run lean. Here are some better scans and logs.NewFuelSystem-flow-117-scale-ve-20percent.hpt

[C5Z06TwinTurb]

Latest run and adjustments.
PS.. If I am not doing something right please let me know. No one is replying so I am started to feel like I am doing something wrong.

NewFuelSystem-precision-changes-IAT-changed-reverted-VE-precision.hpl
NewFuelSystem-VE2.hpt

[edcmat-l1]

VE pyramid.jpg

Your VE looks like a pyramid. The 105/100 Kpa values shouldn't be the highest point.

Some of the injector data is incorrect.

Your displacement is incorrect. That should have been the first thing changed for a stroker.

The PE is too lean.

You're logging way too many pids. No reason to be logging fuel tank level or pressure or half of what you have selected for that matter.

The main problem with not making power though is it's not making any boost. I saw maybe 112 Kpa. That's about 2 PSI.

If whoever is working on this can't tell these things you might wanna consult a pro. You may end up hurting it. If you happen to fix the boost leak before you get it tuned correctly, you're going to have real problems.

[Alvin]

I agree with Ed.

[C5Z06TwinTurb]

VE pyramid.jpg

Your VE looks like a pyramid. The 105/100 Kpa values shouldn't be the highest point.

Some of the injector data is incorrect.

Your displacement is incorrect. That should have been the first thing changed for a stroker.

The PE is too lean.

You're logging way too many pids. No reason to be logging fuel tank level or pressure or half of what you have selected for that matter.

The main problem with not making power though is it's not making any boost. I saw maybe 112 Kpa. That's about 2 PSI.

If whoever is working on this can't tell these things you might wanna consult a pro. You may end up hurting it. If you happen to fix the boost leak before you get it tuned correctly, you're going to have real problems.

Thanks Ed, yes agreed my VE table is ugly. I will take your note and do some more research and pulls to adjust.

Regarding injector data, this has been a PIA over the last couple weeks trying to get the right values. I used the data from GM characterization on Injector dymamics website. Could you correct this for me or shed some light on what is incorrect. I have seen other post where others have mentioned its easier to make the change than to advise. If so I would be grateful.

Man that is a good catch, I never thought to double check the displacement. I made the change! I agree if I actually start hitting boost it would be dangerous so I have made those changes as well.

You're logging way too many pids..... while I agree in theory but in reality I have been making many changes and also taking some beginner courses learning things so most were added for some reason at one point. I will reduce for a more focused approach.

Many thanks....

If you are able to add the injector data please do so here as this is the latest with your changes suggested.

EDs recommended changes
Engine-displacement-VE-scale-EDrecommendation.hpt

[gtstorey]

Gen 3 ECM's will get "laggy" if recording to many channels.

[C5Z06TwinTurb]

Gen 3 ECM's will get "laggy" if recording to many channels.

Thanks for the clarification. That makes perfect sense as I have seen this some.

[C5Z06TwinTurb]

I agree with Ed.

The part I didnt mention is the guy who was working on my tune is an HP Tuner instructor. To his credit the VE table is my hack job after the new fuel system was installed. He seems quite knowledgeable I just think he missed the displacement during our session.

[gametech]

The part I didnt mention is the guy who was working on my tune is an HP Tuner instructor. To his credit the VE table is my hack job after the new fuel system was installed. He seems quite knowledgeable I just think he missed the displacement during our session.

Remember there is a big difference between knowing how to operate a software suite vs knowing how to tune a car. Some of the guys on the pcmhacking forums are knowledgeable enough with the software to write their own tuning software and custom operating systems, but still have difficulty with basic tuning.

[C5Z06TwinTurb]

Yep makes sense, I am a software engineer so i can relate lol.... i enjoy learning and geeking out on air fuel and fire. I think I spent a week researching PCV and catch cans.... appreciate the tips.

[Alvin]

I sent a person from my shops to one of those tuning schools. Thought it would be nice if someone was trained by a different person.. That way I'm not just cloning myself.

Anyway. They tought the tuning school copy paste with labels to fix secondary VE tables.. and I then lost all faith.

[C5Z06TwinTurb]

408 TURBO ID1050 INJECTOR SCALE.hpt

ok guys I spent the day researching and making the corrections Ed suggested. I scaled the injectors and other sections so I wasnt at the top of the VE table. Hoping this is a good baseline to start adding boost. Let me know if I nailed it

[gametech]

408 TURBO ID1050 INJECTOR SCALE.hpt

ok guys I spent the day researching and making the corrections Ed suggested. I scaled the injectors and other sections so I wasnt at the top of the VE table. Hoping this is a good baseline to start adding boost. Let me know if I nailed it

I think you may be misunderstanding something. Unless you are trying to reserve the last row or 2 of your spark table for a "high boost" setting and still run full spark on low boost, there is no reason to scale your tune in this case. This has nothing to do with a VE table limitation. That being said, if you do end up scaling your tune, it is MUCH more involved than what you have done.

[C5Z06TwinTurb]

I think you may be misunderstanding something. Unless you are trying to reserve the last row or 2 of your spark table for a "high boost" setting and still run full spark on low boost, there is no reason to scale your tune in this case. This has nothing to do with a VE table limitation. That being said, if you do end up scaling your tune, it is MUCH more involved than what you have done.

Thanks for jumping in, but to clarify—my PCM is a P01, and while it doesn't have the 63.5 lb/hr hardcoded IFR cap like the E38/E67, it does have limitations that do warrant careful scaling and injector characterization when using large injectors like ID1050x

The bigger issue on the P01 isn’t just IFR—it’s that it lacks proper injector modeling like short pulse adder and has limited resolution at low pulsewidths, which can absolutely cause lean conditions at idle, cruise, or transient when you're running big injectors without scaling or correct offset/min PW data.

So no, it’s not just about “reserving spark rows” or VE limits—this is about maintaining fueling accuracy in a PCM that wasn’t designed for injectors this large. I’ve addressed that in my changes, and everything is scaling consistently across airflow and spark. Don't take my word for it as I am a newb... but I did spend a few hours researching and these articles are from experts. https://injectordynamics.com/wp-cont...SteckScale.pdf

If you see something specifically wrong, feel free to point it out. I error prone and forgetful, Im human.

HowSpeedDensityWorks16.doc

[edcmat-l1]

You don't "scale" injectors or a tune just for the sake of it. It's better not to unless you have to. In this case, you probably don't have to. Start without scaling it and if you end up hitting the airflow hard limit, then start scaling by small amounts until it's gone.

Furthermore "scaling" injectors really has nothing to do with low pw control.

And the VE still looks ridiculous.