I was at the dyno yesterday after 2 runs with the stage 2 pulley I swapped in my 2.9 and did my final run and ran nearly identical to the regular stage 2. The shop people said there must be some detonation going on because the pcm pulled timing and tried desperately to keep the motor rich and which it successfully did keeping it no better than 10.5:1 and at times hitting 10 flat. Hell even the standard stage 2 pulley ran identical a/f ratios. Whats going on here?! How come I've heard stage 2 and 2.9 is the "safe" way to run a smaller pulley on the stage 2 tune and even some people are running 2.8 fine? Why's my car wanting to be a bitch and is my problem something that a good tune can fix?

 

I know this is a stupid question, but did you unplug the battery while you replaced the ring so it could relearn? That makes a world of difference if the computer sees boost pressure earlier and higher than anticipated.

 

If you mod or change something you tune. Its that simple. Thats why people break stuff and then whine about it.

 

No I didn't, I didn't think anything of it because I assumed the people with stage 2 who were running smaller pullies just swapped it out. I'll try that after I get my gauge setup installed.

Yeah makes sense but how come people on here running the stage 2 untuned with smaller pullies?

 

They just assume its creating more power but have no idea whats really going on. They don't have HP tuners or have someone to tune. They want more power but don't bother checking AFR or monitoring it with a wideband. At least you had enough sense to have it checked.

 

Shrinking the gap on your plugs a little may help until you can get a tune done.

 

Thanks man, I'm not very knowledgable about tuning but the shop I went to said they could tune me. Is the detonation problem I have something that could be cured with tuning or must I have other supporting mods?

 

OK you will need at least 3 things if you are not tuned. I'm not tuned and I run the 2.9. I will be soon though.It's the best thing to do.

1. You have to disconnect the negative battery cable for about 10 minutes then connect it.

2. You should be running one step colder spark plugs with a gap of .40 or even .37

3. Always run nothing but 93 octane.

 

Loose those NGK's at .040. Replace them with ZEX plugs part number 82003. They come pregapped and you will get your power without detonation. I had the same issue, as have other with those plugs and that gap.

 

I did everything but number 1. I plan on getting a tune but I'm not going to try again until I get my gauges....too risky if you ask me.

 

Reset ECU and change the plugs!

 

Listen to this guy. He is right!!

 

How come you say the BKR7E's aren't enough?

 

The ZEX's are great plugs.

You detonation is largely due to the tune. If you have good gas and good plugs that is all you can do besides tuning.

 

1) Low octane. You may have gotten a bad tank full. It happens.
2) High AIT2 temperatures. Intercooler system may not be 100%. Any way to check it?. Do you have a log of the run?

Pierre

 

i have stage 2 with 2.8, NGK -1 at .35 i think...i get a small hesitation in second gear, should i open the gap? what you guys think

 

do you have the updated stage flash from GM?

 

Ah that's a good question distillion I forgot all about that. It has helped a bunch of people.

Including distillion and I.

 

can you get a tune instead of the gm flash?

 

if he watned to go that route, then ofcourse.

 

I asked the dealer who installed my stage 2 originally in April and they said all they could do was reflash the stock tune back in. I would need a new VCI # to get any updated flash...is this true? What are you guys telling dealers to get the new flash?

 

tell them to do their ******* job and give you the newest software from GM.

every time im at the dealership I ask them to check and make sure im fully up to date.

they have given me flashes twice since i bought it.

 

Tell him he's full of ****, or find a new dealer! I've received updates either by asking for them specifically or the techs will see something that they think I will, need, want or like....I love my dealership that I go to now. Try to find one that will work with you.....one other note is they tend to want you to be in warranty to do the reflash for free.

Ok, I have a list of updates that have been put on my car....which one will allow me to put the 2.9 pulley on a GM stage 2 flash and see the 5HP and 10TQ or so gains that we 'think' we should get?

 

my cars been flashed at my dealer about 3 times.
find another dealer.

 

People NEED to start reporting ******* dealerships like this to GM. I will look up the customer service # tomarrow so we can get this kinda crap fixed. GM sends out update to tunes and TELLs the dealers to give it to customers. Your dealership was trying to double dip or they just suck.