Sooo... forced induction. Yeah.

[unknownhero]

Well, I've been thinking about going F/I on my tC for a long time now. I can't ever seem to make up my mind about what to do or how to do it or to what extent to do it... I've read a large collection of threads about it in this forum, but I still end up with bits and pieces of the ideal way to do everything. I'm very handy mechanically, but forced induction is a new territory for me, so I'm trying to make sure I cover all of my bases before I even consider making a purchase. Anything I do with the exception of ECM dealings will be handled personally by me.

Lets get started then. Heres what I'm thinking:

I want to spend the least amount possible for the highest quality kit, obviously. I am looking to create something around 250 horsepower, at no more than 8PSI. The big idea is to have a little more zip without having to build the engine up or completely trash my fuel economy, since I drive a lot. I have the TRD exhaust kit already, so I imagine it should be suitable for anything like this. I like the looks of the Dezod S1 kit a lot.

With this in mind, what sort of modding will be necessary?

From what I understand, I will probably need to upgrade the stock clutch (and I was thinking about adding the limited slip differential too?) Should I do one or both?

I also have picked up that I may want to put in a larger fuel pump. Is this necessary, and what is my best option for doing so?

Of course - supercharger or turbo? I like the looks of the turbo kits out there, but it sounds like a supercharger is more consistent and easier on the engine internals. Is this true, and is it even enough difference to worry about? This brings me to another question as well...

I've found a few TRD S/Cs still around on ebay for something like k. I know they were discontinued a few years back, so are they even usable on an '09 model? I know most of the parts on the first generation tC are the same or very similar, but I wasn't sure if that holds true in this case.

The ECM. It needs to be different... That is pretty much all I really know. I've seen mapping for the TRD S/C mentioned, is that the option you would want with any type of F/I? Are there other maps or devices to consider? Where would you need to get this done, the dealership? Is tuning necessary after this change, or are these things one and the same?

The engine oil... I saw it mentioned that you should probably run heavier oil with a turbo. What sort of weight would be preferable?

I don't really remember if that was all I had to ask, but it does cover the main stuff. Any recommendations are greatly appreciated. If I missed any necessary components that I need to modify or replace, feel free to mention it. Thanks in advance for any help!

[navylife59]

Quite an extensive list of questions. That is a good thing. Here it goes.

1. Most quality turbo kits come with excellent install instructions and provide tech support. If you are mechanically inclined and have the right tools, it is fairly a straight forward install.
2. Best to stay away from the TRD S/C due to the simple fact that they will not support it any longer and parts are going to be a booger to get. You will probably want to do the standard bearing kit upgrade and will need to boost up to 12PSI for your power figure.
3. Most turbo kits come with everything that you need based on their Stage level that you choose. I would wait till you hammer down on a specific kit, call their tech support, and see what supporting mods that they suggest
4. Only the TRD S/C kit comes with a flash upgrade. It takes an authorized Toyota service center technician using a very expensive Toyota Tech Tool to accomplish this. Some higher priced higher staged kits come with a pre-programmed piggyback controller. It works ontop of the ECM by intercepting signals. Unfortunately, only WOT fuel trims can be successfully altered.
5. 5W-20 weight is stock. The TRD S/C requires 5W-30. The same for turbos. Some may run a 40 weight for track cars. Either way, it is highly suggested to install a good oil cooler.

[unknownhero]

Right, I had expected as much about the S/C. I mostly liked about it the street legality. That brings me to a big question about pretty much any turbo: do they cause any problems with being street legal? I understand CA is pretty picky about things like that, but since I don't live there, will it matter? I still need for my car to be street legal, since thats kinda my main vehicle... One thing that made me wonder is these conflicting quotes from the Dezod website:

Dezod set out to make a streetable, complete, OEM fitting turbo system, with lots of useable power; the secret to the kit is truly the area below the powerful HP and TQ curves, which prevail as ideal for the daily driver who seeks more power to challenge the occasional highway threat or red light rev. Whether your looking to make the daily commute more enjoyable, make the occasional track appearance or be a local hero on your street block, this system is ideal for your tC. With consistent design, quality components and Dezod brand name reliability, this provides YOU, the best bang for your buck!

So it sounds like what I want, but near the bottom:

All turbo systems where designed and intended for off-road use only

That aside, I'm really liking the Dezod kit overall from what I've seen. I've been looking at the S1 or S2 kits, and the only difference is the engine management they include. Does anyone happen to know if it makes any difference to have the more expensive management at the boost levels I'm looking for?

Oh, and what kind of fuel economy can I probably expect to get if I push it to 250HP? I get 30-32MPG combined average now. I don't mind giving a little of that up for some speed; but if its going to take me below 20-25, I may have an issue.

[navylife59]

The Vortech S/C in the TRD kit is great for the 2AZ-FE. The Achilles' heel of the kit is the TRD add-on parts, IE the torque tube, the torque tube bearings, the idler pulley bearings, and the S/C housing main bracket. Once all of those are replaced, you will have yourself a great setup for a DD and it really shines putting power on in a corner. Turbos have lag (even the best kits) which makes for a bit more footwork keeping the engine RPMs up (boost) while cornering. Some people will change out the inner (S/C) bearings but they are not required. The Vortech S/C is spec'd to make up to 20PSI in it's adiabatic range. Making 15PSI-up, switching to the ceramic ball bearings help to spin the impeller with more efficiency at those higher RPMs (S/C gearbox).

OK, now about those Dezod quotes. No snake oil here. What they state has truth to it. The first one is a claim and the second is a disclaimer. In the first quote, what they are talking about being "streetable for a Daily Driver" is that the kit is setup for a broad power band range with usable low-end torque. Also, the turbo's trim level is better matched to the 2AZ-FE so that lag is minimal for throttle tip-in and WOT usage. MPG is taken into account. This has nothing to due with being able to pass emissions or ordinance inspection.

The second quote is the standard disclaimer used by aftermarket parts companies either because they can't get DOT, 50 States legal certification for their product or, most likely, don't have the capital to spare to get certification.

[westernmass-tc]

i was just browzin through this thread, and im still wondering, do you need to upgrade the clutch if you run turbo, around the 8psi range

[tmr263]

Wouldn't need to.

[navylife59]

For DD no, but if you drag race you tC at the track or increase your boost at a later date, you should upgrade to a Stage 2+ as a minimum.