redlineblueline

I am wanting to custom turbo when my warrenty runs out in a bit and I have the $$. In regards to the block and the auto tranny what all upgrades would I need besides the following:


Block:
Connecting rods, pistons, cams and cam gears, fuel pump, injectors

Tranny:
High stall convertor, new shift points, shift kit if there is one?

Assorted:
Wideband 02 capabilities, injectors and pump, boost controller and turbo timer, and of course all of the stuff for the turbo system. I also want to run a ~50 shot of nitrous through the turbo and also the nitrous intercooler system. And when I have the power I will also up grade to brembo big brakes in all 4 corners.

Anything I am missing or other parts that may fail around 10-12psi and a 50 shot or I need to get that power to the ground.

CTCOBALTSSS

Good luck bro.

celicacobalt

the turbo timer is a waste of money at those psi. i would also forget about the nitrous as well but the intecooler n20 would be fine. cam and cam gears arnt nessecary either. IPT transmissions makes parts for the auto tranny so talk to them. if you wanna get the power down you will need nice sticky tires and lowering springs and possibly motor mounts and strut bar.

Halfcent

Questions:
Do you wish to keep the car street emmisions legal?
What are doing about wheels (stock or aftermarket)?
Is there any reason in particular you want nitrous? I ask because you can reach this engines max potential without it by just using the turbo itself.

I'll answer everything else when you get back to me.

SS33

You probably wouldn't need to do anything to the valvetrain for those boost levels. Unless you plan on rasing therev limiter as well. But the heads on the 2.2 eco should hold up to about 10 psi without giving you troubles.

As far as the auto is concerned I can't help you much there, other than to say that the auto tranny will give you a few headaches when trying to route all of your piping and the downtube.

Wideband is a good idea for sure, but you will also want to look at running colder spark plugs.

Beyond that tuning is going to be your biggest problem. You'll either hafta wait for the aftermarket to get creative (trust me, give them time) or for HPTuners to begin supporting the 2.2 Cobalts.

If you can't wait for those options you could go full standalone, but be prepared for a lot of headaches, or make sure you have deep pockets to get someone else to handle the headaches for you. Megasquirt is a great option, but you will need to be very handy with the electricals to tackle this one.

Hope that answers most of your Q's. Feel free to ask anything else you might be unsure about.

NJHK has a great write up that goes more in depth about all of this, I'll see if I can find that link for ya

SS33

I completely forgot to say hold off on nitrous. If you want it that bad add it in after you have a RUNNING turbo car. Get the hairdryer all installed and tuned before you start adding an additional source of power.

If you want to run it just for the intercooler spray and purge, than you'll be okay, but I wouldn't put a shot into the engine until you've been running the turbo for a while and have all of that tuning under control.

redlineblueline

I want to keep it street legal, I wanted to go with the nitrous to keep the boost down when I'm daily driving the car and what not then throw the switch for another 50 horses or if I could controll the boost a bit better and get the same effect. Wheels are after market right now I have 17x7 with 205-40/17 Khumo ecsta asts.

redlineblueline

I want to run the highest boost I can with out having to build race engine. I'm guessing 10-12 as a conservative number. If 15-20 is acheviable with the same parts as 10-12 then thats what I'll run at.

SS33

\

HE was asking if you wanted to keep it Emissions legal. Not street legal.

This will make a huge diff. Some states (not MI thank god ) require sniffer tests to verify that you're car is running within allowable limits. Some states can even fail you for anything under the hood that isn't stock

Slapping a turbo on a car and the corresponding fuel will raise the level of emissions from your vehicle.

If you're state doesn't require this inspection than you are golden. If you do have to pass a sniffer (like in CA and other places) than you are limited to what you can do.

For the turbo timer, I disagree with whoever said it would be a waste of money. Sure it wold me more critical for a more advanced set-up. But it's relevance has less to do with PSI than it has to do with the type of turbo you use (more specifically the thermal efficiency of the design you choose i.e. water cooled, ball bearing, etc)

As for boost levels if you design your system properly you should be able to start at around 10 psi and then bump it up when you are ready. So long as you get the manifold you want and a turbo that can operate in the range you desire you can adjust boost with either the boost controller or wastegate springs.

I would still recommend starting low, at like 10 psi, and get everything tuned first. Than start trying to up the boost once all of your baselines are solid.

If you plan ahead though you can use all of the same piping, intercooler, manifold, and turbo for both boost levels. Fuel will be a different story however, and takes us back to tuning again and the problems that face the 2.2 cobalt currently

Halfcent

Ok, here ya go...

The parts you need to replace are based on your HP goals. Not the amount of boost you want to run. However, if I make the conversion, it sounds like you want to make 250 HP from the turbo alone, and have 50 extra available to tap via nitrous. The first part of that goal is resonable, the second is not. If you want 50 extra horses available to you, use a switchable boost controller, not nitrous. The turbo is legal on the street (in most places), nitrous is not.

So now, you need an engine and tranny combination capable of around 300 HP. With that that goal, you should use the Build Book section for a 400 HP engine and pretty much follow it exactly. It will include rods and pistons at a minimum. And for 300 HP, it's all you will really need.

To replace the rods and pistons means taking off the head. If you are going to do that, use ARP head studs to put it back together. It's just another $130, and it's MUCH better then bolts.

For your goals, you don't need to do anything to your valve train. Leave it alone. If you are going to push into the 400 HP range, then replace your valve train with Ferrea parts and the GM performance timing gears.

Get a high stall torque converter, 3000 RPM. That should be all you need to do for the 300 HP level. Above that, you will need to do expensive upgrades to your trans to handle the extra torque.

As for the turbo itself...

Right now, nobody can do one because we have no software solution for our engine computers. You could do a stand alone unit, but you will no longer be street legal. Until we get some software, you, I, and everyone, won't do any turbos on the L61 Cobalt.

So therefor I won't bother to talk about the turbo itself yet. Everything else I talked about you can do right now, still run normally aspirated until the software comes out, and be completely legal. I know, cuz' I'm doing it right now!

redlineblueline

For the pistons what should I do the compression ratio at to be able to keep it NA and be ready to switch to FI when the softwares out.


Halfcent, I know you had the tranny custom built, what all did you have done to it besides the high stall. And can you point towards a switchable boost controller?

redlineblueline

What about OBD emissions testing would that cause problems with ^^^ as the actuall sniffer tests because I know PA does an OBD test first then if you fail then they do a sniffer test but here in KY I dont believe they have it anymore.

Rusty

first of all a turbo timer is not that expensive and generally a good idea for any turbo setup to simply cool down the turbo. and how do you have an n20 cooler with no nitrous?

there are many things to consider when doing this turbo project. you need first to figure out what your goal is. not necessarily HP or TQ wise, but is this going to be a daily driver? track car? weekend car? do you want to pass inspection? etc. once you figure that out, you can decide which turbo to go with and that will also help decide how much motor work will be done. you must realize how much strain a turbo setup will put on the car and you will have to beef up a lot of things.

motor:
this all depends on how much power you are expecting/wanting. i'm not very familiar with the 2.2 specs, but i'm sure some internals (pistons, rods) may have to be replaced with forged parts. also you will want to have a goal compression ration which will be determined by your head, pistons, and head gasket. a good CR will help the amount of boost/power you can accomplish.

fuel:
you will want bigger injectors. how big depends on what turbo and how much boost. you will also want to probably upgrade the fuel pump, again depending on your setup. a good fuel pressure regulator may also be desired.

suspension:
you will have a lot of power, so your car better be able to get it down to the ground instead of spinning your tires all day long. polyurethane mounts, strut bars, shocks, struts, springs, trac bars may all be part of your suspension forumula depending on how fast your car is. also your axles will almost definately need to be replaced. the stockers aren't that strong and a good launch with a turbo setup will snap them right in half.

trans:
i dont' know how much power your stock trans can take, but a different converter will probably be necessary along with other beefed up tranny parts.

tuning:
here is your biggest problem. cobalts can't use the S-AFC's and Greddy e-Manage systems that other turbo guys can use to adjust the fuel trim. your tuning options are limited, expensive, and HIGHLY important. you will want to monitor many things such as A/F (via wideband), exhaust gas temp, knock, KR, as well as other things I'm sure. also, with a custom turbo setup with this kind of tuning, your car will run VERY differently depending on the weather. you may have to essentially tune your car every time the weather gets hotter, colder, rainier, foggier, etc.

all of this depends on how crazy you want to go with your turbo setup. a small turbo running minimum boost may be cheaper and give fairly good gains. however, the bigger the turbo, the bigger and beefier everything else has to be. I would highly recommend doing A LOT of research before diving into a project like this. good luck!

redlineblueline

THats why I'm here.

SS33

And for that you will def. be ahead of the game.

As for compression you will want to run lower than stock (anywhere from 8.5:1 to 9.5:1) to keep things safe. Of course someone will always argue that higher comp equals more power at the same psi levels, but it can also cause detonation, which will spread that 2.2 out onto the concrete nicely, lol.

Like halfcent and I have said though the computer is going to be your biggest obstacle to boosting the 2.2

But that just gives you a great opportunity to research, research, and research some more.

Once you've got all of that done you could actually start pieceing the kit together while you are waiting for a computer cure, unless you plan on buying a full kit.

Good sites for info aside from here include, j-body.org (check the boost section under forums) and ecotecforum.com (NJHK's site)

here's a link to a really good write up by NJHK

clicky for eco turbo how to

redlineblueline

I'm gonna peice it together. I think my biggest obstacle when I actually start is going to be figuring where to place/bend/mount all of the piping.

SS33

That will be the toughest part of piecing together your own kit, especially with an auto. But where there's a will there's a way man. You may have to sacrifice a little charge tube diameter to get the overall length of piping down. Time will tell on this, as nobody has done it on a balt themselves yet, as far as I know

If you are set on doing that way the first pieces you will need to figure out will be the turbo and manifold. I think most guys have been going with either a super 60 or a T3/T4 hybrid with an a/r from .48 all the way up to .63

Again what you choose here will depend on your ultimate goals, a smaller turbo will give you better low end response (less lag) but will be limited on the total psi (or cfm in reality) that it can flow. On the other hand a bigger turbo will not be as responsive at lowere speeds/rpm but will allow you to up the boost further down the road without upgrading

So once you decide on the power goals you are aiming for then you can lock yourself into a turbo and get the biggest purchase out of your way.

Next you can start looking at manifolds (as the turbo will dictate the flanges you need). Tubular style is better, but for most set-ups a log style will suffice, save space, and be much cheaper.

Once you have those two pieces you would have what you need to basically start mocking up some of your pipes.

redlineblueline

I take it I have to scrap this idea: https://www.cobaltss.net/forums/2-2l-l61-performance-tech-45/turbo-piping-question-22491/

SS33

Yeah, like I told you in that post you won't be able to use a N/A header in a turbo set-up.

Oh well though, you can always run the header until you're ready to go turbo, then sell it someone else

redlineblueline

true and its all nice and wrapped too.

redlineblueline

You all think 2.5" exhuast is good or should I go any higher. I'm worried about over the axel clearance.

Brian MP5T

Umm, Bad INFO..

SS33

Thank you, that's what I was saying.


And 2.5" exhaust should be sufficient. Once again some will argue that you must go full 3", but unless you intend to run north of 20 psi than the 2.5" exhaust will not really be too much of an impedence.

Freer flowing exhaust is almost always a good thing for turbo apps, but you hafta look at bang for the buck. And like I said for a moderate boost (~10-15 psi) you will not see a huge difference between 2.5 and a full 3" exhaust.

Not to mention the additional money and headaches involved in routing a full 3" system

You should be more concerned with the max size of charge tubes you can route. 2 1/4" may be the best you can do without crazy long runs of pipe

SS33

^^I hope someone proves me wrong here though (on the charge tubes). But I haven't seen a turbo kit on the cobalt yet, so I don't know exactly where you will be routing everything.

It is helpful to have the battery already trunk mounted though, thank you GM

redlineblueline

I saw on crateenginedepot or something that there was a FI prepped block for like 3500$ after labor and what not, what would my prepped block run? Halfcent?