mechguy79

Hello all. I am beginning research into a turbo set up for my 2000 Nissan Frontier with a KA24DE. I'm new to the turbo arena, but not to wrenching.

I am looking to build a custom turbo set up but would like to get power similar to a Mazda CX7 which has peak torque at 2500RPM and puts out ~250ft/lb. I think this set up would make a great streetable truck.

Has anyone tried this route? All my reading so far is always high HP and takes a bunch of RPM. I am not interested in having to spin to 6K, I want the power where it is useful to me, which is between idle and 4K.

Any guidance is greatly appreciated.

janus

Hi there,

sounds about right concerning your plans for the torque band. I'm planning out a similar turbo project for my 2.0l four banger at the moment, but i'll be using a VNT/VTG variable turbine turbocharger from an Audi TDI engine.

I see the KA24DE is a undersquare engine design (longer stroke) as i'm sure you already know, and imho that would make it a good candidate for a torquer engine anyways. The static CR is pretty low so you should have no problems with throwing some mild boost at it, maybe up to about 10 psi intercooled would be my guess, but that would be the first thing i would try to research.

Depending on your personal abilities or finances, the other main problems would be mechanical integration of some turbocharger (as in fabbing, etc), choosing and sourcing a suitable turbocharger, and doing the re-calibration of the ECU. The results could be pretty nice depending on how in detail you decide to go, but it would be interesting to hear what you are expecting as for the reliability

I'll stay tuned for questions, as i've been through some of that already in my project run.

Greetz

MPR

Looks like a Garrett GT2252 turbo (52mm compressor inducer, 72 trim, 0.51 exhaust A/R) or similar would do the trick for the 2.4L. You could run between 8-13psi which will net you approximately 200-250hp(crank). Torque numbers should be higher than that.

Peak compressor efficiency for that turbo on this engine comes in around 3000rpm which will be where your peak torque is. At 2500rpm you're already at nearly 75% efficiency, so it'll spool quick between 2000 and 2500.

Good luck with your build.

WORPeclipse

I'm not 100% sure what they would make on your engine, but the Nissan/Garrett t28 makes 250 and the t28r makes 290 on the SR20's. I'm sure you could make close to those numbers. And I'm sure with the higher comp and bigger displacement you will prob spool it as quick if not quicker than the SR20. You can prob get one of these from guys doin a SR20DET swap and upgradin their turbos. There is a big thing on the SR20 forums about this turbo and the Nissan/Garrett t25 turbo. Lists model numbers and all. I dont have the link to it but I was reading up on it last night. The main guy that was talkin about it was a engineer( I think he said for Garrett). He had their spec sheets and maps for them.

MPR

^A given turbo will not make a fixed power number on a specific engine no matter what. It will make power based on boost, engine displacement and rpm. Depending on the turbo's efficiency map and flow characteristics will determine where in the rpm range peak torque and hp is produced.

So to say X turbo made 250hp on an SR20 and Y turbo made 290hp on the same engine, means nothing. The main difference is it would require about 9-10psi boost to make 250hp from a 2.0L and about 12-13psi to make 290hp on the same engine, give or take. It basically just means they probably ran a bit higher boost with the t28R. Running each turbo with the same amount of boost on the same engine would yield roughly the same peak hp and torque, but at a different rpm.

WORPeclipse

They are both at the same boost. On the same motor. Have diff trim wheels if I am understanding what I read correctly. I will just find the link to the specs on the 2.

--------------------------------------------------------------------------------

Then why is it with a t25 on a DSM and on the same car you can swap in a 16g. The 16g will make more power at less boost than the t25. The 16g is more efficient than the t25 and moves more volume. So can't the nissan t28r be more efficient than the t28 and or move more air?

MPR

If that is the case, then the t28R is providing the same boost level more efficiently, thus, the cooler air entering the engine is resulting/allowing the higher power output.

janus

just wondering if there were any news on this?

Speed_Unleashed

I dont know about the t25 and the 16g on the DSM but i do know they are a litte liferent in size from a t25 that comes on a nissan...not much but still... i know this because I have an SR20DET RWD and rebuilt a few of these and with the leftovers from these I rebuilt a T25 from a DSM and they are a bit different, anyways
the T28 is a thrust bearing turbo as where the T28R is a ball bearing turbo hence why its more efficient... and also a T25 from an SR20DET is bigger than a T25 from a 300ZX twin turbo

anonymous

I have lots of experience with boosted ka24de motors, and they can be real torque monsters.

I would suggest a used t25g from a redtop sr20det, you can usually locate one for under $100. Go to ka-t.org and browse through the dyno section of the forum. There are lots of t25 builds on there. Peak torque on a t25 setup is usually around 3.5k and I have seen as much as 300ft-lbs with these turbos. You may get it to peak even sooner with the truck intake manifold.

There are also a lot of supercharged ka setups starting to appear, which would be better suited for your desired powerband.

The stock block is proven to be reliable until around 400whp. After that the stock rods tend to bend. The stock block has been over 500whp, but the rods bent shorly afterwards.