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First Modification for the Daily

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I have a 2002 Firebird with the 3800 series V6. It's the Y85 code with a factory GU6 (3.42) gear and i'm finding that it needs more power. I found a lovely Turbo kit specifically for these 4th gen V6 F-Bodies that i'm about to buy. It's complete with a wastegate and a T4 Turbo. What i'd like to know, is if i'm missing something here. I'm coming from my first car, the 1978 Firebird that had no computers or anything like these modern cars. Will i need a Tune? Will it bolt on and work right away (assuming all goes well)? im thinking some moderate boost btw, nothing too crazy.

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Yes you will need a tune to re-flash the PCM in order to re-map the air/fuel mixture caused by the forced air induction of the turbo. You probably need to replace the injectors to supply more fuel while under boost too. Also your exhaust system will have to change in order for the turbo to be mounted and work properly. I hope a tuner, new injectors exhaust manifolds, and air routing tubes are all part of the kit and everything fits under the stock hood without any serious modifications.

Another thing about the turbo kit is how is the turbo lubricated? Do need you to provide a means of feeding engine oil to and a return line from the turbo or is it self oiling?

Does it come with an intercooler that you also have to run the plumbing to and from?

Are there any "recommneded" parts that are not included in the kit?

Those are the all the questions that come to my mind, for the moment. Others may have questions or comments too.


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the kit im looking at is the exhaust headers, a crossover pipe, waste gate and the t4 turbo. it has an oil line included and will indeed fit under the stock hood. It was custom fabricated to fit under there. New exhaust is no big deal to me, ive got enough pipes. There are also no 'recommended' parts.

As for the cooler, i've found one for a few more bucks that i can buy separately.   

will i need to poke a hole into the oil pan for the oil to feed into the Turbo?

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Read your directions thoroughly first (or multiple times), but I would guess that the answer is yes, some sort of feed and return line back to the block or oil pan is necessary. Any idea how many pounds of boost you will be running?

I will be honest. The lack of both an included PCM tuner and a recommendation of new fuel injectors is a red flag to me about this kit. I suspect this kit is a builders kit for an experienced engine builder or racer, who might already have a tuner and may have made other tweaks to the bottom and top end of the engine. With a fuel injected motor, putting a turbo or supercharger on requires changing the air/fuel map. So I would challenge the company you got it from how they think the stock PCM is going to compensate for all the added air that the turbo is going to bring to the party. When you add more air, you have to add more fuel to keep the air/fuel ratio as close to stochiometric (14.7 parts air to one part fuel) ) as possible.  Today ideal AFR is actually closer to between 12.8:1 to 13.2:1.

Another thing to consider is under hood temperatures. Compressing air generates heat. That could result in raised coolant and under hood temperatures. So keep an eye on things. You don't want a melt down or a fire because of excessive heat built up in the engine compartment

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Im not going for anything crazy with the boost, like maybe 10 psi. Im trying to get something that will let me have fun with it without blowing up. I'll see if i can ask them about the PCM specs and all.

But that leads me to another thing: will my stock engine internals handle a small psi like this?

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The L36 Series II 3800 is a strong motor and with restraint on the boost psi, it should hold up. Just remember that the compression ratio in the L36 is 9.4:1 while the Supercharged Series II L67 motor was reduced down to 8.4:1 and was built to handle forced induction. So you may need to start running premium gas to help prevent detonation. Another observation is the throttle body on the L67 is bigger to get more air into the motor. So you may want try to locate one from a junkyard (I am assuming that it bolts up to the stock intake for the moment too since the intake between the L36 and L67 are different).

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I feel inclined to point out that i spun a bearing in the original V6 the '02 Firebird came with. i bought a Bonneville V6 and swapped the intake, mounts, etc, to make another V6 for the Birdy. Im really hoping that engine block is the same as the L36 with the 9.4:1 Compression. (i didn't change crank, heads, valves, cam or pistons.)

 That's another thing, how does the whole PSI work? Do you change the turbine inside the turbo? or does the size of the turbo generate the PSI? I feel like this may be my very last question. 

and for the record, i've already looked this up before but i dont retain any information when im just scrolling. 1 on 1 is how i learn this kind of stuff. 

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PSI / boost is managed by the waste gate. The turbo is driven directly off the exhaust gases of the engine. Typically spring tension in the waste gate is set to open at a pre-determined pressure/tension, thus controlling boost.

The size of the turbo will impact the amount of added air flow you pump into the motor.

For the record, a Series I and a Series II 3800 engine are very different engines even though they have the same displacement. Bore and stroke are different because of a one inch difference in block deck height between the two engines.

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