I was having a discussion today with the service manager at my dealership, who runs a Ecotec drag team. He said the reason cylinder 4 breaks is because it runs the hottest. He said to make sure there is enough fuel. I told him about Blown 4-banger running 11.8 when his let go and he said the AFR was too lean. He said 10.8-11.0 max for the Ecotec. He acknowledged it was a tad on the rich side, but that will keep the motor safe.

One of the mechanics has an '05 SS/SC with a 2.5" and 100 shot on stock internals. No issues yet and he has had it for several months now. His is set for a 10.8 AFR.

Thought you guys would like to know.

 

Wow great info, I guess that is going to be my A/F ration when my pully and injectors come in

 

wow, good info.

 

Thanks alot man, mine is running lean right now on the top side so I def gotta have that bumped down!

 

good info and when i go get my new tune i am gonna lean that motha ***** out!! lol

 

what ???? did you not read the post

 

Don't Worry...He'll be able to join the ranks of the other KingLeaners that are able to say "My car used to be a little faster... until the motor blew!"

 

you know i had actually thought about this...i mean didnt everyone say that the gm stage kits and even some stock SS/SC ran a lil rich? I wondered if GM did that for a reason but this is great info

 

Yeah I think the GM Stage kits command a 10.6 or so. Deffinately safe.

 

well that is good news. i was only gonna go to a 2.7 but now its time for 2.5

 

from 11.5 to richen it to say 11.0 how much power is sacraficed giver or take?

 

That is not guarantying that the pistons will last, but will last longer. 20 psi on the stock cast pistons is a lot to ask for. You maybe making 280-300+WHP (depending on tune and supporting mods), but the M62 is probably consuming 90+ at the crank that we never see. That's why the Tag turbo is making so much power. They are using a more efficient compressor.

Honestly I couldn't tell you, but I wouldn't worry about it. You can either make a little more power and chance it, or sacrifice a little power for reliability. No contest IMO.

 

forsure, my LC-1 goes in tomorrow, when tuned on the dyno i was about 11.5to 11.6, i may bring it down to 11 tomorrow and keep it there as the mods continue, a 2.7 is small enough anyways whcih im running with no cooling mods yet, the dual pass with surge tank should be in the car sometime next month, also got my eye on an intercooler pump that flows 7 times more than stock and an aftermarket or secondary heat exchanger.

 

Sticky this...?? Important info i think...

 

What's that off of? Where do you get it?

 

this is very important, Im setting my stuff to 11.3 at least later on today, Im at 12.0 right now.

 

been runnin @11.2-11.4 ..... guess thats why my car is still running

 

I'm going to set mine down to 11.0 - 11.2 just to be safe.

 

I'm still runnin mine at 11.5 at least. You need to make it so that the motor can take it, not kill power for the whole motor. Intake temps will be way down with new cams and head work, plus the forged and coated pistons should take it.
Rob (FAST06SS) told me he ran his at 12.7-13.0 AFR and never blew it up...

 

just a heads up...the word is enrich, not richen...but damn great info...i just hope i remember this when SCT releases the tune for the 2.2

 

awesome info!

 

in the high 11's before but now commanding around 10.7 10.8.

 

great info!

 

What is the factory stock A/F ratio set to?

Thanks,
Mike

 

makes alot of sense.