3rz Rockcrawler Turbo Build Questions

Yeah, it's not an easy choice at all. I debated for a long time with mine. The biggest thing to consider is that the engine itself isn't very efficient at 2000rpm, and even if you have boost there, it still won't be. If you choose a turbo that will flow the same as your engine, it will feel way more potent. You will still make boost in lower rpm when you load it down, but you will really make power where the engine itself wants to make power.

 

Now the turbine flange will come into play. The GT28 series has a T25 flange and the GT30s have a T3. Having a manifold with the T25 will complicate any kind of upgrade to something like a GT3076 or even the T3/T4 discussed below.

That's a typical Chinese T3/T4 hybrid that is kind of between a T04E-46 and T04E-50, both of which you can still find compressor maps for. The turbine is an actual Stage III T3 based on the dimensions. It is sub-optimal for a 3RZ IMO and I think a 0.82 turbine housing is better, but I would still expect it to spool pretty fast and do decently on a stock engine under 5,000rpm. They are also a lot easier to find with an internal wastegate that will simplify the exhaust plumbing. It also shares a T3 turbine flange with the GT30 so the existing manifold would likely work for both. You'd probably be looking at 230-250bhp with 3" exhaust and no intercooler.

 

The T30 maxspeedingrods turbos all had a larger turbine diameter of 65mm, which as I understand it would have slowed the spool time. With the exception of the new BB one https://www.maxpeedingrods.com/prod...-turbo-gt3071-up-to-30-bar.html?search=GT3071 which can be had with a discount code mid $500 range. I went with the pulsar tubro for a little bit more b/c it was well recommended & listed the compressor inlet as 3". However it arrived with a 4" compressor inlet so essentially the same specs as the maxspeedingrods unit.

As for the ebay manifold, others have used them, but the lower rear mounting hole is too high. So you have to grind it. I was concerned about the tubing being super thin.

I ended up getting a flange from https://www.mazworx.com/store/p/43-2RZ/3RZ-Exhaust-Flange.aspx and then welded up pipe fittings to make the manifold similar to this: https://youtu.be/C938m6upCUw?si=zg6xKxSb6tlanCwa

This way it's all at least sch10. It was a pretty easy project. You're better fabricator than me, should be a slam dunk.

 

this one has the 0.82 turbine housing.
https://a.co/d/fds325z

 

It says that, but the product photo is of a T25. Caveat emptor.

The difference at that turbo size is that 3" housings don't usually have a surge ring while the 4" does.

 

That turbo has the 65mm turbine Inducer. As it was explained to me on a 3rz this difference in wheel diameter is too big. Causing Lag. A 3071 has a 55mm/60mm turbine.

 

gotcha. So I’m looking for something that has closer to the same inducer/exducer diameters with a 0.82 turbine housing.

the 3071 has a 5mm difference between the two vs 10mm on the one I posted. I see now. I’ll keep looking.

 

https://www.pulsarturbo.com/product/psr3071-gen2-dual-ball-bearing-turbocharger/
This is my usual recommendation for the rz engines. Great spool, great powerband, and great flow. There is even an internal gated option for it, but pressure is on the higher side at 11.4psi. This turbo with a .82 will still give solid response while also making plenty of power up to just over 5k. I always recommend pulsar for budget stuff because I have a local friend that runs one on his k20 AWD civic hatch making 1150whp at 65psi and it's lasted 3 race seasons now with no issues.

 

I went ahead and ordered the $149 unit on Amazon. That paired with the $175 manifold and $70 wastegate should make for an awesome combo. Wish me luck.

 

Good luck. Just make sure to check it over pretty well and make sure it all looks good. I'm always skeptical about the really cheap units, especially in something that goes out in the middle of nowhere. It seems people have had decent luck with them though

 

Since I have a good audience here in someone else’s thread, lol, any rock crawling clutches y’all recommend? Centerforce has three options I see. So does LCE. Marlin didn’t seem to offer them anymore.

 

I've never ran anything fancy just a Napa clutch made by Luk. We'll see what happens when I get my turbo up and running.

 

Yeah I usually just run Aisin stuff in all my Toyota stuff. Just wondering if there is something better for a boosted crawler.

 

Give clutch specialties a call in Canton Georgia. He made me a dual friction clutch that should feel close to stock with organic on flywheel side and ceramic on pressure plate side. He said should be good to 400tq and slip nicely. He recommended it for off-roading.

 

Nice. I went ahead and ordered the dual friction unit from Centerforce. Probably overkill but I don’t want to drop the trans if I don’t have to for a while.

 

Better to be overkill than underkill build 2.0 is coming together!

 

Could you post a picture of the rest of the cold side and the full hot side?

 

Of course! Anything specific you want me to try to capture? Just promise no hate on the early days stainless tig

 

Just getting some Ideas for plumbing with a forward facing intake. Is that all 2.5" tube?

 

2.5" piping, water to air intercooler, 3" downpipe, with equal length tubular turbo manifold.