Stage 2 retune and 2.8" pulley

[blkbalt06]

I was curious to how a 2.8" pulley would run with the stage 2 tune. i have heard just fine since the stage 2 tune seems to still run a little rich. but i wanted everyone else's opinion on this. either way, if i did run the 2.8 with the stage 2, it would only be temporary.

blkbalt06 added 22 Minutes and 44 Seconds later...

also....do i need to purchase gm's stage 2 in order for a dealer to reflash? if not then i'll piece together my own kit

[blkbalt06]

bump???

[IMADreamer]

This seems to be a popular mod however if you talk to tuners and people with some actually knowledge of what's going on with the stage 2 tune and the LSJ they will tell you this is a bad idea without a custom tune. Essentially you are taking a tune that is designed for a larger pulley and then mechanically leaning it out with the smaller pulley. This is basically guessing and praying that you are hitting safe AFRs. If you do this you MUST run a wideband AFR gauge. Even then chances are when you see things start to go wrong it's too late. Basically the same thing will happen that is happening with the guys running the 2.6 pulleys on the custom tunes, you are going to starve the #4 cylinder and blow the ring land.

There have been one or two guys that this has happened to so far and I'm sure many more are going to have this problem when the weather changes for summer.

The bottom line is running the 2.8 on the S2 tune is extremely risky.

[blkbalt06]

ok, well if i did it, it would only be for a short period of time. my friend has efi live v2 which supports the 2.0, he just needs his laptop back

[light'balt]

As far as the stage 2 reflash by the dealer, When I asked for my parts they also gave me a certificate with the serial number and information for the dealer about the reflash. I don't think they'll reflash without that. But you never know till you ask.

[IMADreamer]

Originally Posted by light'balt

As far as the stage 2 reflash by the dealer, When I asked for my parts they also gave me a certificate with the serial number and information for the dealer about the reflash. I don't think they'll reflash without that. But you never know till you ask.

I actually don't think they can. That is the code for the reflash that they need to access the flash.

[blkbalt06]

ok, i didnt know. thanks. im thinking skipping all of stage 2 and just waiting for my friend to get his laptop back so we can tune.

[Recarobalt_RLC]

you say its only going to be for a short amount of tme but just a little bit for you to think about... i know i did a little more then you but i melted one of my pistons and crack the other three after only an hour of safe driving and only a few hard pushes on it... i had a 2.6 pulley with 60# injectors with a custom tune to keep up with it all.. i found out i need to keep it cooler and i need stronger pistons and rings... but it goes to show that it can completely **** up in am matter of a hours...

[IMADreamer]

Originally Posted by Recarobalt_RLC

you say its only going to be for a short amount of tme but just a little bit for you to think about... i know i did a little more then you but i melted one of my pistons and crack the other three after only an hour of safe driving and only a few hard pushes on it... i had a 2.6 pulley with 60# injectors with a custom tune to keep up with it all.. i found out i need to keep it cooler and i need stronger pistons and rings... but it goes to show that it can completely **** up in am matter of a hours...

good point. It really only takes one WOT run to blow the ring land.

[Misery5567]

I was running Stage 2 tune on the 42# Stage 2 injectors with a 2.8 pulley.

I ran it for about 2 weeks and then started noticing I was getting bad knock after 6K rpm (it was leaning out because of the pulley and the injectors were too small for the 17 lbs of boost it was making.)

I had the presence of mind to order 60 lb injectors and went and got it professionally tuned. What I came away with was a nice strong, safe tune with AFRs under 12 past 2500 rpms. I even gained 3 mpg My 42 lb injectors were at about 120% IDC. The 60 lb injectors never go above 30% IDC Much more room to go on those with other mods.