Last weekend I took my car for it's first tuning after a heads/cam change over the winter. Had very disappointing results due to early detonation. The car was put away last Oct with full tank of 91 octane with fuel stabilizer. Living in Maine 91 is the highest available. Topped off the tank with little over 12 gal of 93 octane in New Hamshire. Is it possible that the octane was still too low to cause early detonation?
The compression across all eight cylinders 195. The tuner recommended going to a tr6 plug versus the ac iridium 41-110.
Also a 160 thermostat. Any help or other suggestions would be appreciated. I can't see keeping the timing set back so far that your not making any real power.

 

What compression ratio are you running and how much timing was the tuner able to crank in? What's the AFR when it starts knocking?

 

I'm going through the same think. you need to add fuel in VE table. If your doing it yourself you need a WB to watch your afr's at wot. I was pulling so much timing it was robbing all my power so i was just messing around and added a 10% across the boost section of the VE table. I went from 4* of timing to back up to 12* but i'm running rich so i have to fine tune. I'm new to tuning i tryed everthing excpet ve and that worked but you need WB and hp tuner pro. Tell your tuner to redo your VE table and i bet that well do it. Why would you put stablizer in your tank never use that junk in your vett just looking for troble, but i don't think it's your fuel it's in the tuning. GL

 

I had AI do some 243 heads opened to their 226cc package and asked them to leave them at stock height, which should have been 64.5. The tuner backed off timing all the way down to 14 deg, but didn't see any difference at all, as soon as he brought near the 5 g's it would start detonating. I can request his exact numbers where he left it. He said that he's being seeing a lot of fuel issues lately. Is 195 lbs of compression too high for pump fuel?
thanks

 

I'm running an f-1c with 24psi of boost on 9.5.1 on 93oct. you need to add fuel.

 

I know this tuner said that he does 10 stangs to every ls1, but this is what he does for a business, I would hope that doing this for 10 yr he would have a pretty good handle on it.

 

You'l be surprise of the incompetens out there that's why i decided to tune myself. I went with a local place the tuner said i know everything your car will be perfect. Famous last works after over 1k of tuning bills my car was still running like **** so i figure if this moron is trying to tune cars why can't i do it. If your ever in chicago don't go to SPEED INC. So after month of me messing with tune my car is a million times better then what they did they say my motor was to radiacl to tune proporly: what morons. I'm not even a tuner and got it better then they did. The tuner said he had over tens yrs of experience and his tunes the best. NOT GL

 

You know it's kind of funny, that after we left the tuner's shop my wife said "maybe this is something that you should think about doing" she was referring to the fact that he told us that we were the 4th tune that he had done that day at 450.00. The other thing that I also questioned was that when I got into the vehicle to pull it off the dyno that it started and then stalled right away. His comment was that he had just reflashed it and it should be ok now. Well on the way home at each light it would want to stall when the clutch was depressed. I called him the following monday to inform of the stalling issue and he said he would take a look at it when I got some fresh fuel in it. Oh by the way anything after the initial tune is only 150.00. Is it the car or the tuner?

 

So it sounds like he doesn't get the first tune right but wants to charge you again...RUN FOREST RUN!!!

Most tuners will charge you something the second time around IF you have changed something that will affect the tune. You didn't get your money's worth the first time. He really shouldn't have gone ahead and tuned it with old gas and Stable in it..

 

That was is exactly what I was thinking, if he had been seeing issues with fuel why didn''t he ask at the time when I made the appointment how old the fuel was?
My cylinder compression has increased about 15 pounds from 180 to 195 with the new cam & head set up. Is this just too close off pump gas? I don't know of any easy way to back it off some. I didn't think that this was ever going to be such an issue prior to starting some of these mods. Little discouraged at this point.
thanks

 

That's what those morons at speed inc tryed with me. They didn't tune right the first time. They told me to change this and change that so i did what did i know he's the tuner. The changes did absolutely nothing so i took it back. After the tuner had it for a few hrs they call me back and said the car was perfect. I said lets go for a ride wiht the tuner but he stayed in the back of the shop. The counter worker said he was to busy. Got the key right when i started up it did the same ****ing thing omg i went back in and demanded my money back after arging my point they gave money back and that dumb *** tuner couldn't even face me. He said he was the best tuner in chiocago my *** he's garbage. I will never go to that tuner again. Dont get me wrong there are great tuner's out there more goods one then bad, but what gets me is when they glout about how great they are and convince you that your car will run great with my tune and it doesn't then they start blaming and making you change things beause they don't want to put any more time in the car to get it right. On top of it get payed top dollar and when you bring the car back of what the tuner did and get charged because the tuner couldn't get it right the first time is wrong. The tuner wouldn't even talk to me or come for a ride.

 

Couple things---Do you have LT headers ?? It is a MUST to tune with a wideband when using LT's--as the stock narrowband 02's are way off with LT's--Without LT's you can get the WOT AFR close by trying to get the 02 voltages near .900 millivolts---If he tuned it on a dyno--most all dyno tuners run it on a wideband as well---
Also---It is NOT uncommon when adding cam/hds/headers to have your knock sensors fail----They begin hearing new starnge noises from the valvetrain or exhaust and sometimes just get overloaded and quit----When a knock sensor fails--rather than SUBTRACTING too much timing they do the opposite---they ADD timing !!! making the eng ping and detonate like crazy no matter what you do---I have had engines with 14* detonate beacsue of bad knock sensors---before blaming the tuner---make sure your Knock sensors haven't gone bad--- the early C5's are known to go bad--GM changed the design around 2002 ?? ish

 

Shouldn't a top notch tuner know these things?

 

If he is doing 4 or more complete tunes a day he is not getting it all right. He might be doing 4 WOT tunes a day right but there is much more to a tune than just the WOT.
Find a new Tuner before spending another dime.

 

tblu92, I almost thought I was going to have to disagree with you on what happens when a knock sensor fails. But then you clarified that GM changed the Operating System after '02. The two cars (2004 and 2006) that I tuned where I knew they had a bad knock sensor would pull max KR as a fail safe when the knock sensors registered as bad.

Just a word of caution - don't count on your knock sensors keeping you out of trouble from detonation. Especially in a boosted application.

 

Where are the tables that add timing when the knock sensor fails???

I have seen the tables for determining how to pull timing due to knock. Never seen a table that controls how to add timing....

 

The program the tuner's using is HP. The car does have LT headers, he turned off the rear 02 sensors. He did say that you can't rely on the knock sensors with a cammed car.
I will read up on the knock sensors though, since I hadn't heard of them failing.
Can I rule out the compression being too high? It would be nice to cross that off the list.
Picked up new tr6 plugs, oil & filter and will replace this morning. It would be way too easy if it just came down to a colder plug.
On another note, I found that the o-ring was bad from who ever did the first cam change, and now have 46 lbs at idle.

 

tblu92,
You know, now that I think about it, when I called him that following Monday to tell him about the idling issue, I asked him if he had turned off the knock sensors since I never got any codes and he response was "no you can't disable them, and wouldn't if you could". Thanks, this may be it, but if he's been in the business for 10 yr's wouldn't he have seen this before now?

 

Hey tom how you been? The time you spent explaining with me was way more time they spent on my car. There tuner's like you who care's how the customer feel and then there tuner's that won't hear it if they can't get the car right. There needs to be more like you.

 

tblu92,
I'm hoping that it's the knock sensors at this point, the plugs made no difference and I still have detonation. I checked for codes but nothing on them showed up.
thanks