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[Rocketman]

Yep, still doing chips!

If you get the IHI turbo from the turbocoupe you can hybrid it with the stock turbo or with a Probe turbo and have a killer upgrade. Stock turbine housing is a little small for such a large compressor though.

I'm running  t-bird compressor presently.

The turbo as a whole has a T3 style flange and will not bolt up.

[bhazard]

How does a vj14/tbird compare to a vj11/tbird in terms of power and spool time?

My tbird still has its stock IHI but I think its getting a bit rough on the edges in terms of seals and such. 183k miles on it and still no play in it though. Been running 18 psi on it for the last 4 years or so.

[Rocketman]

mazda bits technobabble:

IHI has 3 different turbine housing sizes for the RHB5 series:

12R
15R
20R

Each of these corresponds to the A/R of the turbine housing.

VJ14=12R (stock B6T 1.6L, smallest A/R}
VJ20=15R (stock BPT 1.8L, medium A/R)
VJ11=20R (stock F2T 2.2L, "large" A/R)

^^A/R's correspond with OEM engine displacement so as not to choke it...^^

The small 12R turbine housing will tend to really choke flow top end. While yes it will produce a quick spool, it'll suffer from making top-end power because the engine just can't breathe enough through it. Overboosting will likely be a very big issue with a 14/tbird combo.

The VJ20 housing is larger but will not bolt to the B6T manifold. I'm running a VJ20 housing + tbird compressor on my BPT and its performing very well.

The VJ11 turbine housing is the largest commonly available that will bolt to the B6T manifold. It's a great match to the Tbird wheel. I ran this on my old b6t, I had near full boost by 3000 RPM. The top end was pretty incredible, the car just kept pulling! Never felt like it was running out of breath with this turbo.

So: 14/tbird = quick spool, choked top-end, likely overboost
11/tbird = Sacrifice some spool time, but really start to make some serious power

-Matt

[bhazard]

3000 doesnt sound bad. Dont really want "instant boost" on a daily driver as I'd like a lower rpm range without boost to save on gas.

So how does the tbird turbine compare to the 12r 15r 20r? I know its a T3 flange but if I had a header made for my b6t it would probably get a T3 flange, as I think its a more common flange. Wider turbo selection.

I get 18psi in my tbird around 2500 rpms when its cool out. Full 3in exhaust though.

[J. D.]

Does anyone have a "how-to" on this hybrid idea?  I'd like to see how difficult it is...or is anyone maybe even building them?

[Rocketman]

@bhazard: I'm not sure what the A/R is on the full T3 turbine housing, I do know its larger than the 20R. (at this point it'd be too large and I suspect there would be pretty substantial lag) If you were to have a custom manifold built there are a myriad of turbos to choose from- some are much better choices if your budget allows. The great thing about the IHI RHB5 series is *most* turbo parts will interchange allowing a wide array of "bolt-on" upgrades.


@JD: I'll have to find one of my spare turbos to do a pictoral how-to.

If you're dissasembling the CHRA then its really, really recommended to have the assembly balanced by the turbo shop.

If you're just swapping in a CHRA from a different turbo with a larger compressor, its easy to do, but may require some clever routing of the coolant lines. The wastegate actuator bracket may also need modification but its generally nothing more than drilling a few holes.

[J. D.]

Thanks a ton Rocket.  That would be great.  I'd love to see how it's done.  The big thing is convincing my friend/landlord/mechanic that we can do it.  Step by steps are required for him to be a believer!

[Colorado1]

Where does this go? It was under the back seat-a braided ground looking cable and a black pretty clean bracket. To me it looks like a pretty important ground like to the gas tank. Nothing else was under there but little kid junk. They weren't connected when I found them. If I have this picture thing worked out I have @ least one more to post soon.

[Rocketman]

Thats a ground from the engine bay... It goes from the passenger side strut tower to the back of the head. The bracket... might be from the pass strut tower for the p/s lines? not sure on that.

[Colorado1]

Engine was my first thought but didn't see any similar type grounds. The next picture probably has something to do with this mess. It's a gold coated bracket just hanging from a group of wires by a plastic tie. The picture is from beneath the  brake fluid reservoir. I'm on the phone but @ my dial up computer so I'll load it here if I don't get kicked off.

[Colorado1]

Here it is. On thick group of wires just like above in the pic. It's got something to do with this I think.

[Rocketman]

I don't know of any small brackets on the engine that are critical to operation or reliability. I think that holds up part of the harness?

[Rocketman]

BTW, this is where that braided line connects:

 

This is another ground on the front of the head:

 

[Colorado1]

Got it. I did put one up front-someone put a similar looking ground on a bolt to the plastic timing belt cover & couldn't see the purpose. The bracket w/the wire I found goes to the engine/plastic intake piece-well@ least it fits there right.

[azgtx]

That first bracket you show goes on the front on the head for support for the plastic J pipe.
Clay