Combining STS turbo kit and TRD S/C kit

So I have a predicament. While driving my Tacoma, I have decided I want some boost. But of course this begs the question of what kind of boost. I already turbo'd the KA-24 in my 240SX, so I was thinking of doing S/C just to get the experience, but turbos are so fun. But S/C's make more useful power, or at least you have to think less while driving them to get useful power. But a turbo can haul more at highway speeds, and as this truck is my primary method of moving everything I own, that matters. Dyno charts from both show a far better looking curve from a S/C below 3k, but a turbo's gains are substantial over that. And there are numerous arguments between them. Two kits I've found seem relatively plug and play, as far as boosting a stock NA engine goes, so difficulty for either is a wash. Efficiency is very similar between them. So ultimately it's which power curve looks better.

Which leads to using both power curves. Basically using the S/C to maintain boost up until about 2750 RPM. Once I hit that, both of them make about the same power, because both can maintain the boost level at 6 psi. Then the turbo takes over once the S/C starts to choke out at 4600 RPM. The S/C's drag at that point goes away more or less, because the pressure change across the compressor goes to near zero, so it's just free spinning with air blowing past it. On the other side this makes the turbo a slight choke at low RPM, so while your boost will be full, you'll have a slight drop in power at the wheels. I feel like there's a way to get around that by cleverly repurposing a wastegate to act as a bypass for the drive turbine. I'll get to that later.

The whole concept of the project is to take two kits that are relatively independent and easy to install, and merge them together with minimal extra tinkering. I've boosted a car before that wasn't made to be boosted, so I understand the relativity of "minimal extra tinkering" when twin charging a motor. However, since the turbo is remote mounted, and the supercharger sits right on the engine, the two don't get in the way of each other. The S/C takes air from the same spot the turbo drops it off, so the two should merge together nicely.The only thing that really seems problematic is if the fuel system can handle it, though leaving it at 5 psi seems to be working for people on both S/C's and turbos, and since max boost isn't changing, I don't expect air flow to change much, and thus not much change in the fuel requirements, just a more flattened out torque curve.

However, one thing to consider. I haven't seen many people running intercoolers on their turbo'd trucks, I've seen zero engine bays with water-air intercoolers on their S/C's. This is probably because of the low boost and the lack of need, but if you run air through two compressors instead of just one, you'll get an extra heat load that you need to account for. There's still enough space in the front to be able to put an intercooler, which is where the people that use them have mounted them. But this turbo kit has it's pipe to the throttle body on the passenger side. This is the same side as the S/C's intake, which means that I'd have to run the air back to the driver's side to feed into the IC. It'd be nice if instead the pipe up to the front just ran on the driver's side, but this may not be viable. I'm not sure on the clearance or spacing available to run pipes. I don't think it'll be as easy as rotating the compressor housing, but if it is that would be great. If someone's got this turbo kit installed and could eye up the clearances that would be great.

Also being considered as a solution to this conundrum is just running another pipe directly on top of the IC to get air back to the other side, or even using a second IC mounted behind the radiator with air flowing in the opposite direction, though I don't think there's clearance for that and mounting it would be a pain.

 

Welcome to TW. Sounds interesting.

 

Well that's a hell of a first post... Someone actually did this years ago; installed a TRD blower and APR back mount turbo. Not sure how that combo ended up. Think he finally folded after so much money was invested.

 

FYI TRD blower has water to air innercooler.

 

Correct me if I'm wrong but doesn't the sts turbo kit essentially put a turbo where the muffler was? With that being said the mufflers on the Tacoma are on the passenger side of the truck/drivetrain so my guess is that's why the kit sends the air back up that side of the truck. I would think moving the sts Kit the the other side of the truck would be a project in itself let along adding a TRD supercharger to the mix. In any event good luck and welcome to the boards!

 

ur looking at 900RPM of turbo time in that case

 

google "m90 compound boost"

 

Your theory is flawed, particularly the bolded part. The S/C will compound the turbo's boost (and compound the heat as well). Your mid range power will be impressive but as RPM's raise. the boost will be limited by the S/C.

Ultimately for this to work like you want it to, you need to do a few things:

1st, get an oil-less turbo because the STS's oil scavenging design sucks.
2nd, you will need to install a bypass for the S/C for the higher RPM's.

If you want the best of both worlds, the URD S/C kit the kit you want.

 

IIRC u cant even check ur oil with it.............renders dipstick useless I think

 

this guy sounds familiar

 

The replacement for displacement is forced induction, but as the cubes go down, the cost goes up!


Twin Charged 4.7l Tundra by Lextreme
03 4.7l non-VVTi
8.5:1 Comp
4 bolt main conversion
STS Turbo System
TRD Supercharged System
Direct Port 200hp Nitrous system.

 

Bad ass

 

http://www.dragzine.com/news/video-bres-cackling-4-cylinder-3000-hp-nitro-burning-dragster/

 

I believe that most of the things your referring to, OP, as far as no intercoolers, is primarily on the 1st Gen Tacomas.

I know of a guy who has a turbo kit for sale right now. Beautifully built by my old friend from PowerFab.

I also have pictures of the twin charged XR, on my laptop. Uses a water to air intercooler for the turbo. They were making 16-18 psi, on the gauge, at around 3k rpms....Don't quote that though, it has been a long time since I have seen the video. Depending on which size turbo, and specs of turbo, it could very well flow much more per psi than the s/c. You know this. My BW EFR turbo breaks the boost threshold in the low 2k rpm range. No S/c necessary. Your idea though, go with it.


Rock lobster, get a V8 and do a damn swap already, man. Seriously.

 

Will it fit in a taco?

 

Sure thing.

 

Very nice but I always had a soft spot for the 427 and comes with free shipping

http://www.karlperformanceparts.com...YS9J8BMU2GhVAKE6a8QwWQE6XCUPjkg7cARoC7j_w_wcB

 

That shop is right down the road from me. I'm going to dyno my truck there in the spring once I tune it better.

 

Nice to know. Let us know the results