gpruitt54

• Where can I read about DIY tuning? I am not an auto tech, so I only want to know what I need to know about the process, and not all the auto tech theory. Is this a reasonable expectation with a DIY tune?
• Once I do this, how much tinkering will I need to do afterwards? I want it to be one-and-done. Don't want to have to fix and mess around to keep things running properly. Is this a reasonable expectation with a DIY tune?
• Locally, Dyno tunes can be had for 300-600 dollars. If a DIY tune runs roughly the same price (tuning device plus tuning program), why would I not just to a Dyno tune and leave the DIY tune alone?

My car is mostly stock (06 C6 base coupe). I want to remove the throttle body lag, tighten up the trans mission shift points, basically wake up the car.
If this thread is intended for auto techs only, please direct me to the right thread for the novice.

Garymorris

Sign up for HPtuners forum and spend about 6 months reading every noob thead and all the stickies about the basics then start with some simple stuff. The gen 4 motors aren't that hard to do basic work on if you start slow and read before you start changing stuff.

Ahrmike

What gary said. HPT! I commented on your other thread.

What I noticed with self vs pro tune is this: A pro will know way more about tuning but they'll be able to do a lot less on your particular car. If you learn how to self tune, you can dial in the daily driving/WOT conditions a lot better. I've tuned my car a few times and it seemed to run great until the weather changed and I started getting some knock because of it. You learn a lot about tuning from self tuning too!

gpruitt54

Thanks! I've registered on the HP Tuner forum. Question from a noob. Can a self tune damage my car?

Garymorris

Of course it can. With hptuners you are using the same software and doing the same "stuff" that any tuning shop would do so you can absolutely blow it up. Now with a stock NA car and basic bolt ons you have to do something pretty dumb to cause serious damage but it can be done. Now transmission damage is super easy to cause if you just start making random changes or trying to make your 6l80 shift like an old TH400 or shutting off all torque management. They are great transmissions but you need to be careful with how much you change. Mine is taking 650whp/600wtq with no problems and just some basic shift time and pressure changes.

gpruitt54

In reading other threads about tuning, I hear guys talking about pre-made tunes that seem to be plug-n-play. As I understand it, plug-n-play tunes are made for a specific car, and are uploaded and used as is. As someone looking for a plug-n-play performance enhancement, can I expect this from HP Tuners? Is HP Tuners for professionals?

Ahrmike

Yes. HPT will allow you to "email tune" with a professional using HPT just as diablosport tuners will. However, there are probably less people in the business of doing this. There are a lot of good threads on HPT on how to start tuning so if you read it and get a little overwhelmed, take your time and go through it slowly. Its not as hard as it sounds - as long as you're meticulous on what you're adjusting and don't haphazardly change everything. When I got HPT, I literally googled every single switch "what does X in HPT do" and there was almost always a thread and a reply on the HPT forum. It goes a bit slowly but its very interesting. You have complete control and if you screw too much with timing/AF/MAF curves/kncok sensor sensitivity, you can damage your car.

My entire set up cost me 400 for the HPT module and 100 for the credits to tune. If you decide to go DS, i recommend diablew - he has a lot of experience and good reviews. It'll cost you 300-ish for the tuner and another 100 for the tune from him. IIRC, he will help adjust the tune for 6 months or so.


HPT also has amazing datalogging capabilities - DS is not bad, but HPT will give you a full real time readout on your laptop, and the datalogging screen itself is customizable.

Orion2011

In a nutshell what a DIY tune will do is:
Tune the MAF table to what your MAF is actually doing vs a stock guess. Every MAF is different would be my guess.
Sets the requested WOT AFR to 12.6(best power) or so, my stock program was calling for 11 something which was way too rich, conservative as hell, GM hedging their bets against detonation.

Without a dyno it would be extremely difficult to impossible to do any real meaningful timing changes.

Then there's the VE tune, "Volumetric Efficiency". This is a fancy way of saying how much air your engine should be able to ingest at x RPM and y load. The ECU has long term and short term fuel trims at correct for variances in this. It is debatable if this is necessary. I compared a canned tuners tune to my DIY and realized it didn't even touch the VE table.

Orion2011

All I said above is done by putting the engine in different modes then logging AFR(air fuel ratio) data and AFR error with a wideband O2 sensor. Then applying the data to the tables. For instance a MAF only mode to tune the MAF and a "speed density" mode to tune the VE table.

The details of setting these "modes" is best left to HP Tuners forum. Each engine generation is different.

Spaceme1117

To do a DIY tune, you will need a laptop, a wide band O2 sensor, and HP Tuners so you are looking at close to $1000. And to be able to do it right, you need to know the theory behind it.

You are much better off getting a dyno tune for your car.

TurboLX

Agreed that it can be a steep learning curve for a beginner. We put together training material for everyone from casual enthusiasts to shop owners and experienced calibration engineers. There is certainly a significant level of commitment required to do the job correctly. But if one decides they'd like to learn, it can be broken down into understandable tasks without losing the science. Just don't expect to be spoon fed and still get great results.

Mike@DiabloSport

Take a look at the tuning options we offer, like the inTune i3 or T2 devices.
They come with preloaded tunes, you pick the octane and load it up.
Instant gains, all done in your driveway.
From there, these devices also offer quite a bit of end user adjustment, like WOT timing and fueling, idle speed, WOT shift points, rev limiter, etc.
Its a great way to get your feet wet with tuning without having to learn everything about your particular operating system.
These devices also support custom tuning, so if you decide to mod down the road and need a specific tune, it can be done by email or with any of our CMR tuning shops in person.

Let me know if you have any questions.

Thanks

Ahrmike

I tuned without a wideband O2 - got a wideband afterwards and my tune is basically spot on.

I did the copy low octane table into high octane, run it rich initally, tune of STFT (turn off LTFT) for the stoich calcs + run it rich initially and slowly pull back method. It worked pretty great - was almost perfect after a few shots. It was a little scary tuning the WOT but with the low octane tables + hammering out the stoich values first, it went okay.

Garymorris

Since fuel trims don't work in PE you were just guessing off 02 voltage or what? You also should to tune the o2 response when they are relocated with headers and you need a wideband for that too. Why take the risk...A wideband is a good investment for anyone who is even close to the point of tuning their own car.

Orion2011

He probably turned off PE. When you do that trims work in WOT. It's risky though. But with the low octane table less so.

Garymorris

I realise that but it's still a terrible way to do it. Why risk hurting something to save $300 on a wideband that you should have anyway?

Ahrmike

Because it was safer than the canned tune that came on my DS? because its possible? The humidity/heat in my location requires way more timing retarding than DS gives on their 91 octane tune (im running 92 octane pump gas) and with my method (no wideband) I was able to dial it in better than DS's one size fits all.

The way I did it is tried and true (HPtuners forum), it IS possibly unsafe - but I'd bet getting your car tuned by a random tuner shop would be similar. I read and researched a lot on what "safe" advance numbers were, backed it off from the low octane tables, ran the entire car rich initially, and slowly upped the RPM and pulled a little fuel at a time.

Yes, a wideband tune would have been better. But all im saying is that my tune is safer than the canned stuff for MY location - and it worked fine.

TurboLX

1) Humidity allows you to ADD more timing in areas that would be knock limited, as it's effectively water injection. We typically have to be softer on timing in arid climates like Phoenix/Vegas than we would in Miami.

2) There is a factory spark vs IAT function that many tooners feel the need to reduce or remove altogether just to add timing. In reality, this curve is pretty good for many cases and the timing should have just been added in the base spark (high octane) table instead. Amateur mistake on the part of the tuner.

Ahrmike

Interesting - I did read humidity does assist in lowering knock potential but for whatever reason, even on factory tune, my car would have to pull a few degrees from fully stock tables. I sort of assumed it was due to the humidity/heat but it could be potentially other issues like gas (we only have one refinery in Hawaii). I did play with the IAT/spark and ECT/spark but I went back to stock since as you say, it seemed to run better in stock configuration. I did remove the advance on the colder ECT temps though so it doesnt mistakenly advance my timing too much if I were to get on it before the car was fully warmed up.