JEEEZ, does anyone tune a car these days?

:cheers:

I haven't gotten any codes on my car. I'm still wondering why so many people are having problems, but it sounds like the newer PCM's are ridiculously sensitive.

I've been running my car for a couple weeks with the open cold-box and NO mufflers (for a track event), and no codes.

Dave, I don't think its more sensitive, they just took so many precautions with safe tuning that the PCM is set to dump a ton of extra fuel Via the high LTFT's be tuned to near +20. The tripping ofa SES light is usually with a combination of mods not a singe one.

Airflow with your air cleaners wouldn't change flow, it is just letting in denser cold air which is still correctly measured by the MAF. Add headers and an intake manifold and you may be at +23 with no code or +24.5 on peaks and set it off at closed loop driving or idle. Its just normal tuning.

You wouldn't think there was something wrong with the design of a cam if it didnt idle with the factory tune so why would anyone think think there is a design flaw with headers or/and intake if it didnt run with the stock volumetric efficiency table?

Someone just e-mailed me telling me that Kooks is working on the 'problem'. There isn't a problem....they need a tune.

I don't know that I agree with your logic, or may not understand it. If the OEM program throws out +20ltrms, then it is running very lean. I understand how going to +25 would cause a problem, but it would have made more sense for GM to fatten up the VE table in the first place. Running the table lean and compensating with extra fuel (via ltrms) is not the way GM usually does things.

A tune can definitely fix anything, but I sort-of agree with ??(kooks, halltech etc) that the items should work without a tune. I would think anything short of a cam should not cause a problem, yet it is (intake and headers) for some. Some people seem to be having problems with nothing more than an airbox.

Thanks for your insight! I've got a scanner coming so that I can check my ltrms. No problems, but I'm awefully damn curious!

Dave

Actually at +20 it is at 14.7 and not lean but allows for a ton of fuel to be dumped. At +24.8 or so it throws a code. Like I said it is a combination of mods that throws the code. Especially ones that make unpredictable airflow changes after the MAF of if you relocate the MAF. A ported TB or intake manifold would be suspect since they get air inot the cylinders differently than the MAF/ve tables predict. Now for the guy that made an exhaust change AND put on a air cleaner.....you made a big change there.

If GM made the LTFT's zero then there was one less way of getting fuel in under adverse conditions so to allow for the biggest control/variance they made it run at the higher end of things since the casual driver doesn't car what the PCM is doing as long as it runs smoothly in all types of weather and in all altitudes. On high altitude places air is less dense and since they don't know where a car is going after they make it, they must make all PCM's operate a car in all conditions. High altitude cars have less range capability.

ok, i just did a dry run using davidfarmer method...without cutting up anything and the filter boxes switch sides and upside down....now the whole intake tubing sits much higher to the point of the hood will not close. i am assuming where the holes are cut the actually air filter boxes are sticking out pass / or hanging pass the fan shroud by an inch or so. can someone that has done this confirm this?

yes, mine hangs down "just enough". You don't want it resting against the radiator, but low enough that the air-bridge will sit in the factory latches.

It's not necessary to switch sides. I first tried this too but had the same clearence problem you have. Just rotate the filter boxes 180. After you cut the shroud they will be lower and no interference. :thumbs:

I cheated and bought a K & N kit..........

I'll have my AutoXRay scanner on Thursday, hopefully, and am curious to see how far my ltrms are off. I've also got a set of straight pipe (cats, but no muffler) for track events, and I've had no codes so far. I'm really curious to see how whacked the OEM tune is.

Who makes it and is there a site where I can see the product software? I like the HPtuners especially for the logging of the timing advance cells that show the exact cell being used when you get knock retard. Makes tuning the spark advance so much easier than auto-tap.

http://www.autoxray.com/

it is a hanheld that can offload to a laptop. I imagine it will be similar to Autotap, only the convenience of not draggin my laptop everytime I go for a ride. You can buy the cheaper version from tooltopia.com, then add the PC cable and enhanced GM stuff direct from them.

Looks good but if you paid 399 ...

HPtuners is 1000 for the tuner versions and has the scanner built in. Single users will be 500-550. That is what LS2edit costs.

I like the portability and not worrying about laptops and batteries.

Let us know how it works out :thumbs:

I would really like to see a before and after dyno on this mod if any of you have done it? If the intake feels cold then I am guessing it is getting something done. I would guess 10-12 HP and similiar TQ gains but it is all conjecture until we get some numbers. I love this idea and am planning to do it (once I get a C6). Hell by that time there will definitely be some conclusive data on this mod..............just cant wait to see if the freebie work?

Cajun

WOW!! That's something that I'm going to have to do! Thanks for the VERY COOL info!! :thumbs: :flag:
Bill

Added to the C6 FAQ.

With VIR next weekend (THSCC HPD event), I finally finished off my DIY airbox.

Here are the two aluminum shroud extentions I made up. Pardon my fabricating skills, but I don't have a metal "box break" for making compound bends. Therefor, this is the best I can do with shears and a pair of pliars!

Anyway, I'm pretty pleased with it. I'll pull the pieces off, rivet it all together, and spray it black.

**I do not have a template to give away or sell, so what you've seen here is all there is. IMHO, if you have the initiative/skill to do this, you also have the skill to figure it out for yourself.

http://www.davidfarmerracing.com/aba.jpg
http://www.davidfarmerracing.com/abb.jpg

ttt, want to make sure everyone sees this final chapter before I let it dye!

david...
 

SO,any issues since you put it on a few months ago??Have you noticed a more responsive throttle??LASTLY,Can you make me one?? :D