I have a 2007 cobalt ls with a 5 speed. I want to turbo it i have $8000 to spend. I want to run the turbo at around 20 psi. I want to know everything ill need including engine upgrades(rods, pistons etc...) tranny upgrades.. what turbo kit...what blowoff valve and everything. Thanks guys

 

it would be more helpfull to give a hp goal instead of a psi goal,because 20psi out of a tiny turbo is gonna require diff parts than 20psi out of a huge turbo, also psi will change with parts put on the engine, i.e. supporting mods. so let us know your goals and we can help alot more than you think. also 8k is alot of money. you could spend half that, and then put the rest in the bank for what youll probably want

 

like a 300-350hp goal

 

well stock head stock cams stock bottom end, it can be achieved
so you just saved a ton of money. others will chime in on the perfect turbo for that hp setup. but a good starting point will be supporting mods.
a good header dp, 3in will be perfect.
are you doing the installs yourself or paying someone. and are you looking for a kit or to piece something together?
with these little questions answered im sure you will get all the right answeres

 

i am definately going with a kit...is there one you prefer..and i plan on doing the installation myself.

 

sub'd

 

You will save a lot by building a custom kit... I price mine near 4500 with a engine build too (rods, pistons, cams, etc.).. That was all labor done by me. But my power goal is higher so the turbo size I am not the best at. But the GT2871 or 76R will get you a range of 280-480's.. somewhere in that area.. you can probably go smaller and get a better curve out of the turbo. That is what they told me to do. Someone else can chime in though.

 

read more and learn about what you need to do.

There is so much information that can be given based on your question. Search and read

 

zzp twin charge. Just do that and it will be even more fun.

 

how do you figure he can achieve 300-350 hp with stock bottom end if the oem rods are rated to only 250 max?

 

trade that **** in on something else and spend the money on that car....

 

^This.


Your wasting your money when you could just buy a TC and tune it. Then you'll be in your horse power range instantly. Plus you may upgrade the car for power but it will still have low grade suspension...etc...

Don't do it.

 

gonna hafta agree

 

Forged connecting rods, Eagles will be fine $350
Forged pistons, Diamond $350
Clutch(your choice but I like Spec2+) $500
That covers the bottom end

Head, you really should upgrade the valves to all stainless at minimum, $250+
Springs $350+

Turbo kit a ZZP Stage 3 will do the job at $3100
A hahn Level 4 LSJ kit at $4200 will bet you there too...

Going off of pretty conservative numbers youre gonna need around 16psi out of a midframe turbo to get to the 325whp area. Something like a GT3076-56T-60a/r or an S259 should get the job done no problem. Then you need a manifold $300, a wastegate $250-350, an intercooler $200-$1200, oil/water lines,downpipe, intake, etc.......

For your trans you should invest in a Quaife diffe ($1300+) or at least an EP LSD insert ($600), and some DSS Stage 2 axles ($800)

Dont forget a catback.


A kit is really the way to go unless youre good at/really into fabrication. $8000 is plenty of money to meet your goals.(and build your suspension......dont listen to the TC nutswingers, its your car, do what you want then go out and destroy them, all theyll be able to say is...."well I have nicer seats"

 

^this

 

there are plenty of stock bottom end 2.2's running huge hp

 

X2

But I'm 18 and my insurance will be too much he'll say.

 

hell im 21 and the insurance on a ss/tc IS too much for what it is. besides that lsd, turbo, and 4 wheel disk brakes isnt worth 10k more at least not to me

 

There are far more differences than the three major things you listed. But for the sake of this thread...there is no point in arguing about it.

Either spend your money and do what you want or trade it in and put the 8k towards the new car. Either way in the end you will have essentially a new car. Just try to figure out which option is not only cost efficent but will actually achieve the goals you set. I'd becareful with building a car from the bottom up unless you plan on doing all of the labor yourself. If your not I would expect you may end up spending more than you might anticipate.