Q: IHI RHB5/RHB6 Spec's
 

Hey,

I've just bought a '91 Subaru Legacy Turbo, as a winter beater ;) It comes stock with the IHI RHB5 turbo. This turbo boosts at about 8 PSI. It's max capability is about 12-13 PSI.

I'm wondering, whether I'd get more boost with an IHI RHB6 turbo, and whether this turbo would bolt-on to my application. Also, any extra info such as the compressor maps/max boost info comparisons between the IHI RHB5/RHB6 would be greatly appreciated.

Last, but not least, I'd like to know whether the IHI RHB6 compressor housing would bolt onto the IHI RHB5 exhaust housing and the mid-section. What boost gains would such a hybrid turbo create. Would it spool up faster than a "stock" RHB5?

Thanks in advance,

P.

Re:Q: IHI RHB5/RHB6 Spec's
 

Im using the ihi rhb5 turbo on my d16z6 setup right now! Tha turbo spools really quick but dies at about 6000 rpm and up! So but this prolly really didnt help you!

Re:Q: IHI RHB5/RHB6 Spec's
 

Well I don't know about compatibility, but the an RHb5/6 combo would spool at the same rate as your rhb5 but push more CFM and have a 'wider' flow map. Sorry I can't help with the actual specs but if you could it would be easy to push more boost and CFM.

Re:Q: IHI RHB5/RHB6 Spec's
 

the IHI 5/6 parts are not interchangeable. The RHB5 came in many different sizes and configurations.

Some of the RHB5s are very small. The VJ11 from Probe/Mx6 should be good for 12 psi and to 7k+ on a 1.6, same with some of the subaru units. Some of the Isuzu units had a very small compressor, I-marks I think.

The centre section from a T-bird should be pretty much a bolt in affair and is about 15-20% bigger than the probe/suby units. This would let you run at 15psi all day long :)

Neil

Re:Q: IHI RHB5/RHB6 Spec's
 

Those Legacy Turbo's are really rare to find in I would mess with it not just as a beater, built that sleeper. Yes the T-bird turbo can be used with the Rhb5 to make a hybrid turbo that will push more air.

Re:Q: IHI RHB5/RHB6 Spec's
 

First of all, thanks for all of the replies.

I did some research on the RHB5/RHB6 hybrid turbo idea, and it's definitely a no-go. The RHB6 Compressor is TOTALLY different than the RHB5 compressor. It would be impossible to interchange them.

I have a different question now. I've seen a turbo on a Ford T-Bird, but I could swear that it wasn't an IHI RHB5 and that it was some kind of a Garret T3...

Which turbo comes "stock" on the T-Bird? Does anyone have specs/pics of that turbo?

If I was to build a "hybrid" turbo from my Legacy IHI RHB5 exhaust housing, mid-section and the T-Bird Compressor, what parts would I need from the T-bird turbo? (Just the compressor housing, backing plate, or would I also need the "wheel" off the T-Bird Turbo?)\

Wouldn't it be simpler to just put in a T-Bird turbo into the Legacy...? Would the T-Bird turbo bolt-on in the Legacy?

What power gains should I expect with such an upgrage, with a fuel system, which will deliver the additional fuel to compensate for the increase in air...?
(Stock HP is 165 and the torque is 181lb)

TIA

P.

Re:Q: IHI RHB5/RHB6 Spec's
 

All the spec could be find here : http://www.geocities.com/ttskipp/turbochargers.htm

Re:Q: IHI RHB5/RHB6 Spec's
 

some turbocoupes had t3's, others had ihi's with t3 flanges

Re:Q: IHI RHB5/RHB6 Spec's
 

What kind of IHI's did the Turbocoupes have???

Re:Q: IHI RHB5/RHB6 Spec's
 

the t-birds came with a weird IHI, it has the same center section as any other IHI, but it has an exhaust turbine housing with a T3 flange. The IHI only came on 87/88 turbocoupes, the earlier ones had a Garrett.

You need the compressor wheel/turbine and housing, that's it. If you can find one with a good centre section then it would be easier to just swap the centre section than to rebuild your turbo with the t-bird parts.

It would be alot of work to install the complete t-bird IHI unit, about the same as a T3 conversion.

Neil