95.5 and 96 3.4 tacoma TURBO problem!!!

The gap

 

Careful when talking psi. 8 psi on a larger turbo will move more air than on a smaller one. The TRD S/C doesnt move as much air / psi, compared to most turbo's, hence the lower performance numbers (among other things already noted).

 

True to a point but psi is psi (regarding turbos)... Only difference is the boost level that a certain size turbo will give at a certain rpm and throttle position. The engine will use 8 psi the same for two completely different turbos at the same rpm, throttle position, and intake temperature (especially with a wastegate) but the important difference in HP is the boost level at a certain intake temperature, humidity level, and like I said rpm and throttle position which differs for every size turbo (except humidity). 8 psi is 8 psi and more moving air getting shoved in the IM means more psi unless the engine was tuned differently.
I don't plan on going above a 12 psi wastegate spring, so I'll end up settling for whatever numbers that will give me on a properly fueled, cooled and tuned setup (did you notice my goal went from 8 to 12 psi? )

 

Not necessarily. This issue is efficiency and heat. If you take two manifolds of equal pressure (8psi) but one manifold is hotter than the other, it means the colder manifold just has more air mass while the hotter is generating more PSI from the extra heat. Following?

So smaller turbo's tend to be less efficient than bigger (there are exceptions of course but lets keep things simple). When you measure boost, it is dependent on a: how much air is in the manifold, and b: how hot the air is. Generally a larger (more efficient) turbo at 8 psi, is pushing cooler air and therefore is moving more air mass (CFM) per psi than the smaller (less efficient) turbo which gets 8 psi with less air mass but higher temps. Im specifically keeping the IC out of the equation.

That is why the TRD blower's power band sucks so bad in higher boost. It uses a three lobe screw (vice the newer 4 lobe screws) and as speed increases, efficiency decreases, and temps skyrocket. There was a guy that calculated the intake temps of the TRD SC at 12 PSI and I can't remember exactly what he had but I remember it being north of 300F. Basically what is happening is, as you raise the PSI of the TRD blower, you are getting a diminished return on air mass and most of the PSI made is from increased temps.

This is why I took my S/C money and got a turbo

To sum it all up, rule of thumb is bigger turbo's give more power per PSI than smaller turbos. But the most accurate thing you can say is, you cant compare PSI between two different turbo setups; especially between a turbo and S/C.

 

Well like you said (I think it was you anyway ) I would sacrifice a little top end for lower rpm boost. My only issue is my truck has like NO room anywhere in the front to put an intercooler... So I might tee the charge pipes into two 1 1/2" stacked intercoolers (if I can find some that small) and tee them back in on the other side. That would also do a better job of cooling the charge air. I really don't want an obnoxious carnival of DIY nonsense in front of my truck but I have plenty time to figure it out.

 

Def. I think I would prefer the smaller turbo but Ill see how this runs.

Why not air to water intercooler? Smaller but a bit more $$$

 

Because I want my charge air less than 180+deg. There are a million and two different sizes and shapes of intercoolers on ebay so I'll figure something out.

And with some tuning and bigger exhaust I'm sure your power will still be pretty epic in vacuum/lower rpms. 3k and up will be way more beastly than my setup for sure

 

Air to water generally cools better than air to air You will still have to mount a heat exchanger up front but its much smaller than a FMIC.

If you are really crazy, get yourself a killer chiller. I hooks up to your IC water lines and uses the A/C to cool the water. Im pretty sure they are only made for Mustangs, but Ive seen some tundra guys use them (not hard to modify to your application. Claims 50-60F drop in temps vs a standard passive cooler. From what I read on TundraTalk, water temps never see above freezing, even in on a 100+ F day.

 

Maybe on a drag truck but an old DD I'm good with the basics. More stuff means more stuff to fail. I'll be ok with a max 150F intake temp and a small IC can do that. I'll probably have to loosen my radiator and prop it above the lowest support bar that sits behind our bottom plastic bumper. Did you figure out where you are going to tap into your coolant hoses for the turbo?

 

Not yet, either the TB hose or heat hose depending on which is easier. I did find some coolan pipes CxRacing provide in their kit that will make things a lot easier.

 

I heard the heater core hose is the best one to tap but idk

 

Thats what most ppl do. But the TB is closer. In fact some ppl just run the TB hose to the Turbo and don't run any coolant to the TB. Not sure if or if not it needs to be cooled...

I get the truck back tomorrow afternoon so Ill be able to start checking things out then.

 

TB coolant lines are supposed to help lower TB tempts..not crucial. Supra guys delete them all the time.

 

Just read up on this and most sites say the coolant is actually there to HEAT the TB, primarily to inhibit ice formation in the TB. Winters are not super bad around here but I think Ill keep mine on...

 

Thanks for the input. I've read clownmeats thread too, def good info. Out of curiosity, did you notice a difference in mpg when driving normally (if you can actually do that with boost

 

I have an 2003 Toyota Tacoma with an sts turbo kit just wondering what upgrades can i do to this turbo kit?

 

Fuel upgrade really. New injectors or extra injectors with the URD port fueler + upgraded fuel pump. A piggy back controller or full standalone ECU to tune.

 

I never kept track of mpg on the tacoma and I put the turbo on within 2 months of having the truck so I can't tell you if I get better mpg. I would assume under normal driving I should get a little better mpg. But between my t100 and my tacoma I fill the tacoma more often because it has a smaller tank.

 

Also methanol injection. With the proper fuel tune and timing you can up the boost by getting a different size wastegate spring. I would stay between 8 to 10 psi. I believe anything higher you'll need to upgrade your internals.

 

Well since the rear mount turbo is strictly for convenient boost than anything, you would probably get the best bang for the buck and very nice results from simply putting some bigger injectors, beefier fuel pump and have that sucker dyno tuned. Anywhere between 300cc and 400cc injectors. No extra resevoirs to keep up on and no crazy electronics that are meant to handle 1000hp cars. I'm not 100 percent sure that a dyno tuner can get that fuel and timing tuned properly by just by rewrighting the maps on your stock ECU, but at 8psi I'm willing to bet you won't need a standalone controler.

Your best bet would be to find a performance shop with a dyno and have him walk through with you physically with your truck while telling him your ultimate HP goals and get his input. No need to go crazy, cuz when you do... you'll get convinced to want to do it properly and find some headers to put that turbo in the front