Need some help. At wits end.

[TitanTn]

I've been working on ironing out issues for almost 2 years. I have tried to get help locally tuning, but have ended up being disappointed for a myriad of reasons. Long story, but here's where I'm at currently.

2017 Grandsport, M7, A&A supercharger, intercooler and bov, long tube headers, 50/50 meth single nozzle, forged pistons, DOD delete, catch can, and a few other small items.

The biggest current issue is that sometimes the rpms aren't coming down between shifts and if you're coasting in gear anything over 2,500 rpms and push the clutch in, the rpms will rise to about 4,000 and just hang there until you turn off the car.

I don't know where to begin. I've attached the tune and a short log file. I'm hoping the issue is clear to you experts. Thanks.

[GHuggins]

Put the rate limits and lower load of the torque models back to stock then retest. Really might want to fix the VE too while you're at it.

[TitanTn]

Put the rate limits and lower load of the torque models back to stock then retest. Really might want to fix the VE too while you're at it.

I'm not really sure what you're talking about (I'm completely green at editing a tune), but I'm certainly willing to give it a try. Are you saying my VE table looks wrong or you're suggesting that based on the issue I'm having - this might be where the issue is?

Thanks.

[GHuggins]

For putting the virtual torque tables lower loads back to stock and these are your negative areas of the model, you'll have to open a second editor with the stock calibration in it then copy the lower loads (one single line is enough going left to right) of each table from 1200 rpms up then paste those back into your current tune then hit calculate coefficients, but not till you paste the values into all of the cylinder airmass tables or all of the map tables.

The rate limit tables are underneath the driver demand tables. People max those out for throttle response, but all you really need to do is multiply them by 3 or 4 on the increasing values. Put all 8 tables back to stock then go from there.

Your VVE hasn't been dialed in. You're not setup for boost at all.

[TitanTn]

I appreciate your help. I'm just as confused though - not your fault - just the nature of this complicated process I think. Number one is I don't understand what you're describing - I'm not experienced at this at all. But even more than that, I've had multiple local tuners work on this as well as some online. Everyone tells me they know what they're doing and describes what needs to happen which sounds technical, complicated, and intelligent. But then the next guy tells me it's all wrong. I just don't know where to go to find the person who definitely knows.

The current tune is from a very reputable shop in Atlanta. They tune cars exactly like mine all the time. All day long. I don't understand how my tune can't be setup for boost.

So I have all the tunes from the last several years. I went back to the custom tune that came with the car when I bought it out of CA. It originally ran good for a while with that (before all these issues and recent mods). Today I took the VSS tables, and some of the Air Mass tables and copied them into my current tune. It does seems to be some better. But the issue is still there. I also played with a few other things from other tunes and some made no difference, and some were not good at all.

I obviously am not a tuner and don't know what I'm doing. I just don't know where to turn. Go back to the tuner in Atlanta and get them to try again? Find someone else? Maybe you, Greg? It's hard to know what to do next or how to even assess my options.

Thanks for any and all help.

[GHuggins]

I thought that torque model looked familiar. Pretty sure they put the same one into all of their FI tunes.

Just showing you a couple of things here since it seems like you don't believe what I'm telling you.

Your VE table as illustrated with boost axis - take note of the 100+ region - the boost fueling area - nose dives off - still set up as NA

Your VE Table.jpg

This is what I changed it to for you. Tried to keep your idle area, but at least this one will be safer. Don't know if the rest is right or not, but from what I've seen....

What was changed to.jpg

Didn't know yours had the pedal progression table in it. Made changes to it too along with putting your rate limits and bases of your torque model mostly back to stock.

[blindsquirrel]

If I had a dollar for every famous-on-Instagram big-name tuner who was found to be a hack after one of their tunes got posted here and gone through, I would have a lot of dollars.

[JASON11WS6]

I see a lot of people blaming tunes for things that are mechanical issues. Not saying that is the case here but it could very well be a vacuum leak or a bad blow off valve. Just things I would look into. Was the car always acting like this after the last tune or did it just start happening all of a sudden?

[TitanTn]

Short version - Greg Huggins knows what he's doing. Car runs very good.

Longer version - I didn't mean to insinuate that I didn't believe you. I was trying to say that my issue is I've believed everyone I've spoken with before and every time someone else contradicts what the previous person said. I am just at a point that I don't know where to turn. But I put the tune in you supplied and the car runs smooth and doesn't have the rpm issue. It's hard to tell with the butt dyno where the power is, but it's definitely fun to drive. I'm going to be sending you a PM to thank you for this and discuss next steps.

So yeah, I've been working on mechanical issues for a while and tuning. It's been a 2 year saga, and to JASON11WS6's point - sometimes it's mechanical and the tune gets blamed. Sometimes it's hard to know for sure. Especially when you don't have confidence in a tuner. I wish I understood how to tweak thing myself, but I doubt I'll ever have (take) the time to get there myself. It's pretty deep and involved.

So a BIG thank you to Greg. I still don't understand all you were talking about, but you definitely knew what you were talking about.

[GHuggins]

I've dealt a lot with hanging throttles and what causes it on these not to mention going in behind some very big name shops and seeing how they mess some things up thinking they're getting "peppier' throttles. One big name shop had one customers wot or nothing - literally. You would touch the throttle and it was wot... Shop wouldn't fix it and the customer had to haul his car home.... I see stuff like this all of the time and I've made my fair share of mistakes that I've worked back through myself, which is part of the reason I know how to adjust that normally found in the background pedal progression table

Really glad it fixed your issue. It will need the fuelling dialed back in for the changed VE wot part of the VE table as this will change wot MAF fueling just because of the % it plays into it.

I was wondering about the BOV being stuck as that will cause an issue like this, but usually won't just hang open like that until you cut the key off.

[TitanTn]

So here is a followup to this thread. Greg fixed the hanging throttle immediately, but the car still needed tuning help so I hired him to do a complete tune. I had to purchase and install a Wideband, but then it was: drive and log a scan, send to Greg, he adjusts, sends tune back and we repeat. This wasn't 3 or 4 tunes. It was many tunes. Greg stays on it until it's right. My car has never driven better and has a ton more power. Starting, idling, gentle driving, aggressive driving - it's all crazy better. Remember that this is after I had a big name in Atlanta do a complete dyno and street tune, and that was after I had been through several other tuners who supposedly knew what they were doing.

I was losing faith that anyone knew how to tune, or that maybe there was something majorly wrong with the car that no one was identifying. I've learned my lesson - that you really have to find someone who truly knows their craft. There truly is a difference, but it's hard to know before you try someone. The performance shop in Atlanta came highly recommended from someone local that had used them. The only difference I'm aware of is that it was an LS car. So I hope this is helpful to others who are looking for a solution. I can only tell you what I know for sure - Greg is a genius at tuning my LT car.

[GHuggins]

I'm glad we were able to get everything right Rob. Just give me shout this next summer and we'll get the hotter ends of the density table too.