Jimster

Does anyone here have a good build sheet or specs and numbers for what kind of power i can make or the setup needed for a T3/T4 M12 type turbo. Ar.50 compressor side, ar.63 turbine side. Installing on an NB 1.8l

borka

iTrader: (1)

Full_Tilt_Boogie

iTrader: (1)

What upgrades do you have in the bottom end?

Jimster

No upgrades to the bottom end yet but i am willing to do some if needed. Just puttlng some feelers out as I currently have 2 turbo options in hand and was seeing if the larger one was realistic or if i sgould just put in the other one from the 2nd gen eclipse. I already have a stage 2 clutch and 11 lb flywheel and will be installing the MS PNP in the next few weeks to start playing with that prior to turboing as reccomended.

Full_Tilt_Boogie

iTrader: (1)

Well in that case you will make exactly as much power as the bottom end will hold, which is itself an inexact number.

Make sure to document it on your Youtube VBlog.

borka

iTrader: (1)

So you have 2 random turbos that you want to base your whole build around?

Have you already sourced proper manifold/downpipe combo for said turbos to fit a miata?

Big turbo will be laggy, but make more power.
Smaller turbo more responsive with less max power.

Stock engines blow up at 250+ hp.

Jimster

I figured that, i was simply trying to get some input like if i could run the larger turbo back on the cutve a bit at lower boost and then crank up the boost as I make the other internal upgrades later to save the repiping if i decided to switch turbos to the larger one later. Also i wasnt sure if the 1.8 would through enough flow in the larger one to spool up before 4500rpm cause if thats the case i should probably stay with the smaller one and have more fun throughout the range instead of just wow factor when the larger one finally spooled up.

Jimster

The smaller dsm has adapters available to mount to the fm log manifold or the ebay cast ones and i will be doing some welding on the downpies and modifying the exhast either way although the larger one has a vband outlet whichmakes things a bit easier on the downpipe fab but is overall a space hog. And yes I would like to plan my build around one of the 2 turbos I already have if either make sense.

borka

iTrader: (1)

You can't just give random a/r numbers and expect the turbo gods to give you an exact spool/rpm plot and expected power.

That's not how this works.

You can run a big turbo at low psi and live with a shitty laggy setup.

But do manifolds/downpipes even exist for said turbos to fit a miata?

borka

iTrader: (1)

Save aggravation and money, go with a true and tried T25 setup with plenty of turbo choices and bolt on manifolds and downpipes.

What ever savings you think you will have from already owning the turbo will be blown away and then some on custom everything to make it fit.

Jimster

So if i get rid of both my turbos and just buy a t25 which i really dont have a problem doing i was just hoping i could use one of the 2 I had since the larger one is brand new and niether one has any shaft play at all. Which T25 turbo will get me around that 250 hp mark most efficiently?

Jimster

FYI, my smaller turbo is a TB2566 of of a 97 eclipse gsx which i thought was basically a garret T25 except for the manifold mounting bolt pattern.

borka

iTrader: (1)

A gt2560r out of a s14 s15 240sx is an excellent miata turbo. Spools great, happy making 250hp and tops out around 280hp pump gas

Jimster

Thanks, i will see what i can come up with locally in that size.

borka

iTrader: (1)

most important thing is to have a standard T25 flange on the turbo with the 5 bolt exhaust flange.
Then you can use any of the available standard manifolds/downpipes, and save yourself money and headaches by not having to custom make these parts.

also standard parts can be sold for good money later, a custom setup with a weird turbo and half baked manifold/dp will sell for pennies later.

josh96821

My car is a very cheap build and had to fabricate lots of stuff. Best bet is to just get a tried and true turbo setup I can tell you from experience that the t3/t4 dosnt fit well and is not ideal for the miata.

andyfloyd

Chinese t3/t4 stuff sucks donkey *********. DSM t25 turbos also suck lots of *********. Get a gt2554 or 2560r. Either of those will spool well, make good power, are well sized for a Miata engine and don't suck *********