Not sure if my tuner is competent

[metaphysx]

Greetings to all and thanks in advance for any guidance. I'm struggling to accept that my tune is anywhere near acceptable after having it back a couple of times to my tuner for work. So frustrated with the way its running, I went out and bought everything I needed to scan and tune myself because I know this is not right. Not being picky, just don't want a car that will hardly idle at all until fully warm, hunting like crazy, requires throttle inputs to keep it running until warm, etc. When warmed up, it stalls coming to stops or the idle hangs at 1,400, then drops and struggles. Needless to say, totally miserable to deal with. Outside of that, actual performance is really good, except driving isn't only that, it involves stopping for lights, etc. Miserable.

The car is a 2002 C5, owned and well maintained since new. 40k miles. Prior to the recent heads/cam/intake build, the car ran great with AR 1 3/4 long tubes, mail order tune from ECS, McCleod RXT clutch, Stoptech ST60/40 brakes all around, etc.

Heads , cam, intake included virtually every top shelf part I could think of to make more power, more reliability. I spared no expense.

CamMotion Titan 4 cam 227/232 113+4 (not a difficult cam to tune and reputation for good street manners)
TrickFlow 215 heads, fully worked over by TEA, milled to 61cc.
FAST 102 Intake, Vengeance Racing ported, with Nick Williams throttle body.
Harland Sharps roller rockers.
BTR dual valve springs
Johnson 2110R lifters
Manton pushrods.
Vengeance Racing 36lb injectors
Melling oil pump
C5R timing chain
ATI Balancer
Calloway Honker
and every supporting part, gasket, etc.

I wanted max effort build that still had good street manners and good road course racing performance. Car makes great power, a bit under 500 RWHP.
I'll attach a scan of the cold start and the current tune and go from there. I'm betting much of the trouble starts there, where a competent tuner would be able to get this right and explains why the return to idle and idle qualities when warm are total garbage. Hoping to gain some insight and either get it to a better tuner, or begin to learn how to work these problems out myself. Thanks for your thought.

[bk2life]

or begin to learn how to work these problems out myself..

start here ----> https://forum.hptuners.com/showthrea...dCDR6D7t30xBWA

[reubone]

My suggestion is to find a new tuner. I offer tuning services but that is not why I am suggesting this. The maf curve alone suggests a tuner with little experience. The timing table has left a lot to be desired and that is as far as I could get giving the benefit of a doubt. Your combo may be beyond this guy's skill level. Sorry

[metaphysx]

Thanks for the replies. I guess his tune is as I suspected judging by the way it drives, as you said, it leaves a lot to be desired. Is it that easy for an experienced tuner to look at the “work” that was done and know either how hard the tuner tried to get it right or the skill level of the tuner? In the trades, I can spot sloppy work a mile away, but I suspect it’s a little harder to learn to “see” a crappy or sloppy tune. I can feel that the tune is crap by the way it runs, or not runs, in this case when it stalls out, hunts for idle, etc. Still would like to hear from any other experienced tuners here for their impressions. I know it’s likely I’m going to have to find another tuner. I was there each time this tuner tried to sort it out. He spent a few hours at least on it so far, between street tuning and then dyno tuning. I could tell he was frustrated. He ended up blaming the 102 intake and larger throttle body. I know this combo can challenge inexperienced tuners, apparently, but I’m not running a big cam with a bunch of overlap and I understand the 102 intakes can be tuned perfectly. Just frustrated here. Thanks for the help and understanding.

[reubone]

I would say that it is easy to assume incompetency more than flat out prove it. With out being able to track the tuning process, there is no way to judge why the tables in a file look the way they do. At least that is how I see it. I have seen some tables that look way off but for some reason or another, The combination responded well to the abstract and would not run on a typical tune. This is extremely rare and usually points to a mechanical incompatibility or failure of some kind. I would like a shot at tuning this combo. I like challenges.

[Alvin]

The injector stuff isn't correct at all. It's setup for a vacuum referenced regulator in the flow rate only. Nothing else is changed.

There is a issue in the idle spark overspeed tables.. a very high positive number in the middle.. you'll see it.

There is a lot of things that don't look correct.. The VE table doesn't look like it's really tuned for this cam.


I'd say you should have plenty to pick up in the tune.

[metaphysx]

I would say that it is easy to assume incompetency more than flat out prove it. With out being able to track the tuning process, there is no way to judge why the tables in a file look the way they do. At least that is how I see it. I have seen some tables that look way off but for some reason or another, The combination responded well to the abstract and would not run on a typical tune. This is extremely rare and usually points to a mechanical incompatibility or failure of some kind. I would like a shot at tuning this combo. I like challenges.

Thanks for the constructive feedback from all. I?m still left baffled how an otherwise really great LS shop would have a tuner working for them who struggles so much to get a tune even in the ballpark. However, like a lot in life, it?s a learning opportunity for me to begin to understand tuning myself. Just hesitant to jump right into it and try and sort out what an otherwise ?experienced? tuner couldn?t get right. Doesn?t inspire confidence for newbies like me. That said, you?d mentioned you?d be up to help me with the challenge? What does that entail, exactly? I?m kind of on the fence between an arrangement like that and just taking it to another local shop that is highly pedigreed, a known name, with a tuner/engineer that?s been tuning for literally decades. Obviously that comes at a cost, but it?s then done and done right, I assume, but I don?t learn anything. Decisions, decisions. Still really appreciate any further opinions. I?d really like to let the shop owner who pays the tuner who did my tuning that he should reconsider their relationship if this is all he?s able to do.

[Ben Charles]

You’d be surprised

[SiriusC1024]

Go get a dyno tune from a reputable shop. Seriously. Spark tables and afr tell me that hasn't been done. There's all kinds of other flaws, too. Looks like it's been setup to make WOT power then cobbled to make it run on the street.

[metaphysx]

Go get a dyno tune from a reputable shop. Seriously. Spark tables and afr tell me that hasn't been done. There's all kinds of other flaws, too. Looks like it's been setup to make WOT power then cobbled to make it run on the street.

That?s exactly the impression I get when I drive the car, actually. It made great power, just under 500 rwhp, but the tuner struggled, spending at least a couple of hours, trying to sort out the constant stalling and driveability issues. In fact, even before it went to the dyno, he spent a couple of hours road and parking lot tuning at the shop. His poor solution was the hang the idle at 1,400 rpm to prevent a stall. This improved the stalling at lights and stops, but as soon as the idle settles back down and attempts to idle normally, most times it stalls.
The shop owner, who is a genuinely good guy, is offering to have a guy that was THE tuner at a highly reputable shop do a remote tune WITH the assistance of the tuner who put the car in the current state. I?ve no doubt the remote tune guy is extremely qualified, you would all know the shop he worked at for 20 years, especially if you?re an LS motor guy, but I worry that the remote tune guy won?t dedicate the time needed to really dial it in. After all, I think he?s doing it as a favor to the shop owner who?s known him forever.
My alternative plan is just to take it to MTI Racing here in Georgia and allow the tuner there, who is absolutely competent, to really sort it out. Decisions, decisions.

[Alvin]

If you were to call my shop.. That build would need to be left for 3 days. Not cause it takes me 3 days to do the thing. I likely can do most of it in half of one day. But to get the cold start, all the driveablity correct, etc. It takes some time. You have maybe 2 but really only 1 good shot at a cold start per day. etc.

The dyno tuning is easy and goes fast. Its the idle, return to idle, stop at a gas station and go to re crank stuff that takes the longest to perfect.