newbs49

A little history
Had headers installed and tuned - no problem car ran great. Spring 2013

Later in year had cam installed and tuned idle hunting began-took car back installer tuned again. Car was better but I was told basically there would be some hunting because of the cam. Late fall 2013

Late last fall 2014 had PRC 2.5 heads, Fast 92, injectors and GM throttle body and harness installed and tune. Drove car home and right in garage for winter. Pulled car out two weeks ago and same idle problem. 75% of the time I pull up to a stop and down to 400rpm up to 12-1300 rpm. Up and down a few times and settles out at 850rpm most of the time. Right now I hate to even drive the car. Should have left it alone after headers and tune,
Any info would be helpful. I don't want to put any names out there about the company or tuner. I don't play that game. Cam is a Comp
Specs are
Adv Dur 283 - 289
Dur @.50 230- 236
Lobe Sep 114
Lift .572 .578

At this point I guess I have to try another tuner but I know how they can be when someone else did previous work. Any ideas or suggestion?

2001 Z06 20955 miles.

Russ K

I hope you don't have an aluminum flywheel or a light weight clutch, as that will really aggravate a hunting idle.

Your cam has 5* overlap, not a big cam, but 5* overlap will not drive even close to stock on a 5.7. I have a 4* overlap cam in my 418 stroker, while the drive-abilty is 10x better then the 10* overlap cam, it doesn't drive like stock.

One thing to do is to enable the rolling idle tables. Use the values from a 2001-2002 Camaro A4 tune. Then you may need to increase the airflow adder table and change the 2 mph airflow cell to .5 g/sec and I have my enable/disable speeds at .63 & .31 MPH. The rolling idle table is enabled as soon as you push in the clutch or put the trans in neutral. So this rolling idle aiflow table will open the throttle when coming to a stop to help the hunting idle. And this is providing the RAF table is correct

And 850 idle is too low for your cam, I have mine at 950.

Can you post your tune?

Russ Kemp

newbs49

Thanks for the info. I can't post the tune, sorry. I had it done by the installer and I don't have any tuning software or eguipment of my own.
Stock flywheel and clutch.

Thanks for your help.

Larry

CTD

Sounds like a nice car & it's shameful your not happy with it. It really does sound like tuning issue's & as Russ mentioned it's not a donkey dick sized cam. I had jumped into the tuning for two reasons, one because I had to & second to figure out the tuner from tooner.

With the modifications you are doing maybe it's time for you to jump in, have you considered it?

Supercowboy

Sounds like the tuner needs to spend more time in the running airflow table. heads and cam change airflow big time. Takes some time but if you log the right parameters it can be done properly. Is the car a stick or auto. Im sure if you go back to them they can make proper adjustments with no charge. Thats if they take pride in there work.

newbs49

I've thought about it but I'm from the old school of muscle car's. My time has past on the new stuff. I may take a shot at it but the equipment is costly...

newbs49

Car is a stick.. I just don't look forward to a 6+ hour drive to get the car fixed again and taking a day off and a hotel....
I put more mileage on the car back and forth to the tuner, then I do driving it in the summer.

daws222000

I see your sig says your from NY, New Era is pretty close to you. Mike should be able to dial you in less then a day so you wont need to stay there.

newbs49

That's my other option. I'm between Nia. Falls and Buffalo. They are just over a hours drive away. I may call them tomorrow or next week.

Thank You

daws222000

Where did you have it tuned first?

newbs49

Like I said in first post. Not naming anyone. Sorry

newbs49

Well car goes in Monday for the week. Hope all goes well.. I just want to drive my car
With out any issues...

tblu92

This is a 100% tuning issue----I have tuned way larger cams in a LS1 LS6 or LS2 and with your mods it should NOT be an issue----It is troublesome however and is a trial and error process------Idle hunting is a byproduct of "dersired airflow" an idle parameter---Also with a cam the base timing should be increased by 3-4 degrees---
LT headers make the tuning even more complex----because the 02 bungs are moved aft 3-4 ft--the 02 sensor readings at P/T are messed up-- too many mods all at once to isolate the exact culprit of idle surging or hunting---but most tuners can with enough time fifure it out---And I am not talking about dyno tuning but drivability tuning

newbs49

Thanks for your help everyone. I should know in a few days.