I'm currently running a 2.8" pulley. I want to go to the 2.5" pulley this winter (while cars in storage.) Other then machine the snout, and 60lb injectors, what else is needed? I'm going to get the blower ported this winter and plan on installing a stock cobra HE in series w/ the cobalt's stock HE.

How street friendly is the 2.5" pulley? Is/Has anyone encountered any problems running the 2.5" pulley?

I haven’t had any problems w/ my 2.8" pulley. Car drives just fine; as it did the day I bought it (but with more power.) I just want to be sure that I won't encounter any problems dropping down the 2.5" pulley, and that the car will be reliable. I don’t want to push the car to its limits and blow up the motor.

As For Tuning, I plan on having INTENSE dyno-tune the car as they did w/ my 2.8" pulley.

 

other bolt ons are definatly necessary. One mod leads to another. when increasing power your gonna need a new clutch, axles (traction pretty much).

otherwise. id say Heat exchanger, 60lb injectors, TUNE, stg2 belt, and you should be good

 

What are your other mods? Before the header,dp, and water injection, I could run the 2.5" safely-but only with low timing. The 2.5" is still reliable as long as you do it right. You'll love the low-end torque increase! They do create alot of heat, so I'm glad to see you're going to add a 2cnd heat exchanger. I would also do the dual pass intake conversion, and water injection to maximize the cooling ability. Make sure your exhaust is freed up, you really don't want to have a cat on there for max flow.

 

I definately suggest a Cometic headgasket and Golden Eagle or ARP studs. The stock headbolts cannot be reused since they are torque-to-yield bolts. Other than what you stated is needed I would get a clutch, axles, motor mounts, upgraded HE, water/meth injection, dual pass intercooler, and a free flowing exhaust to be reliable. I also suggest getting some gauges to monitor everything that is going on.

 

My current mods are:
Poly Motor Mount
Poly Tranny Mounts
Poly CAB's
Injen CAI
J/S Header
ZZP Catless DP
Magnaflow Catback
42.5lb Injectors
2.8" Pulley

I have an Interceptor Scan Gauge to monitor things. I don’t have a wideband because I do not plan on tuning my car... I will have INTENSE Tune it.

Like I stated above, I plan on doing the second HE, and possibly that dual pass conversion when it comes out. I'm going with a stiegemeier port for the S/C.

I'm hoping that w/ the Port, and upgrading the HE system that I won't have to use Meth injection. I don’t want my motor to rely on meth for cooling...

 

You'll NEED 60lb injectors for sure BEFORE putting the 2.5" pulley on. You will need a custom tune as well, since you'll have to run low timing with no water injection. Other than that just scan,scan,scan and have fun!

By the way, "meth" doesn't cool the air. Water cools the air as it evaporates, the meth increases octane, similar to race gas.

 

Save the money on the steigmeier port and get the meth injection. The couple of people that I have seen that have had their blower ported didn't show very good gains...