hey guys i remember seeing that little sucker on ebay, and now i ordered injectors and i cant find that thing, and i def dont want to use intense racings MAF translator :eek: :eek: . so if anyone wants to sell it to me or if you know where i can get it that would be awesome!!!!! Thanks!!!! :D

http://www.zzperformance.com/cobalt_ion/products1.php?id=452&PHPSESSID=0f461846121f3ebdcc741b306cdd5be8

For your information, it will give you the possibility to tune the air fuel curve only in a few percentage range, since the PCM calculate the air fuel ratio by several sensors datas, not only the MAF sensor.

Personnaly, with the 42 lb/hr injectors and this very device and the 2,6" pulley, I have not been able to get the air fuel ratio as lean as wanted, since a correction more than about 7% of the MAF signal get the PCM see it and throw even more gas than needed.

I will try soon a kind of map clamp to adjust the air fuel ratio leaner ...

Don't forget too that some one range colder colders plugs helps for higher boost levels ... Yesterday I swaped my Denso IK20 plugs (same heat range than stock) for NGK BKR7E plugs, it removes a bit of knock.

well i was planning on buying these things, in addition to what i already have on my car in my sig: #42 Lucas injectors, SFPHQ 2.8" non-slip pulley ring, Mini AFC a/f controller, adjustable belt tensioner, and the injector clips. do you thinki will be able to get a good a/f with that set-up? its over 500 bucks so i wanna make sure it will yeild some good power gains,

I doubt you will be able to get an air fuel ratio as lean as 12:1 for most of the RPM's. It could be as low as 10 for the 2500 @ 5000 RPM range. I think we should clamp the MAP sensor to a lower voltage.

how is that possible? right now it is leaner than 12:1 sometimes, why would 2 more lbs of boost make it rich? wouldnt i have to adjust the AFC to make it run that rich? i mean if i didnt adjust it what would stop it from leaning out?

Are your 42lb/hr injectors installed at this very moment ?

Are your 42lb/hr injectors installed at this very moment ?

no i am contemplating ordering that list i posted above

So the reason you will running way too rich is that the 42 lb/hr injectors flows 22,8% more than your 34,2 lb/hr stock injectors !!!!!!

Under part throttle (closed loop mode) it will be fine, because the PCM will adjust the injector pulse width relative to the oxygen sensor readings.

But when accelerating hard (open loop mode), it will run too rich, exactly like I am experimenting at this very moment.

do i even need the injectors with that 2.8 pulley? what if i just use a AFC with the factory injectors? or what about the ones for sale on here, i think they are 38 lbs

With a 2,8" pulley, the pressure in the manifold at WOT will be 6 PSI higher (18 PSI vs 12 PSI stock).

The pressure in the fuel rail is always roughly 60 PSI, so with the smaller pulley, the differential pressure through the injectors will be 6 PSI lower, resulting in less flow.

People with the PSI-FI kit already runs that 2,8" pulley without swapping the injectors, but they are usually lean (near of 13 AFR) for the very last RPM's.

I saw you have a CAI' which tends to run leaner too.

Before swapping the injectors, the best is to install the 2,8" pulley and see with a precise Wideband meter if you're too lean at WOT. The best is not to go past 12:1 or 12.5:1 at the very most at WOT.

Maybe the 38 lb/hr injectors would help a bit, but I think they will flow only 5% more than stock because of the lower differential fuel pressure. So, as an example, if you run a 13.2:1 AFR with the 2,8" pulley and CAI and stock injectors, the 38 lb/hr injectors will bring it down to 12.5:1.

thats perfect, cept i dont wanna spend money on those things! also, i know alot about how this stuff works, with the a/f and all that, i am a part-time performance mechanic. i have like 10 runs with my SS with the 3" pulley, CAI, and magnaflow in my car, and if it will help, i can scan them on here so u can see my a/f with the 3"