UK specs or J-specs for hybrids??

Do the UK spec's have a larger housing than the j-spec ceramics?

Im asuming if they do, there going to be slightly better for a potential rebuild?

Any views guys?

Cheers

Mikey

I think the consensus in the US is that J spec turbos are better, due to the shaft diameter, case wise, either can be machined, so there is little in it, however both J spec and UK turbos seem to last a similar mileage.

J-Specs are bigger.

I would still love to have this proved again but the j-specs have considerably larger internals.

I have also been told that the UK spec turbos have less capacity to be honed out to take bigger hybrids, but thats anecdotal and I have no proof.

There are pictures on the forum somewhere of the internals which show the differences.

JB

There are pictures on the forum somewhere of the internals which show the differences.

 

JB

Which I believe you posted didn't you?? Going back a few years now!

edit: indeed...

http://www.mkivsupra.net/vbb/showthread.php?t=680&highlight=turbo+bigger

Which I believe you posted didn't you?? Going back a few years now!

well yes, but then it would have looked rude if I didnt post a link to my own post and Im scared of the search system, it brings back too many memories

Since then I dont remember seeing anybody confirm that its true and done the same comparison so it would be good to actually have somebody double check it one day.

I think the consensus in the US is that J spec turbos are better, due to the shaft diameter, case wise, either can be machined, so there is little in it, however both J spec and UK turbos seem to last a similar mileage.

wont the shaft be changed as well though when the hybrids are built??

My thinking behind this is that the UK's have a larger exhaust housing and would possibly make a better turbo to build hybrids with

im still convinced despite the speculation and people not liking them, there is potential with hybrids

Shaft stays the same, due to core size, but if you chuck enough money at it then anythings possible, need to stick mine on a RR to see what its making;) made 370 and 390ftlbs at only 5,000RPM at 1.1 bar but aborted run.

Shaft stays the same, due to core size, but if you chuck enough money at it then anythings possible, need to stick mine on a RR to see what its making;) made 370 and 390ftlbs at only 5,000RPM at 1.1 bar but aborted run.

thats a good power figure given the low settings. How do you find the response compared to BPU levels.

I think when I take the plunge I will be using meth as well to maximise the high boost setting ie 1.1-1.4bar are you using meth with your setup as well? not sure to go pure meth given the high boost of a high concentration mix

Here's some data I found on the two turbos during a Google search (I'm planning my own hybrid build soon)

CT-12B (UK Spec Steel)

CT-20 (J Spec Ceramic)

The internal dimensions are given at the end of the documents.

Hope this helps

Andy

Just 20-30% meth to water, so no advantage from meth.

Great find Andy!

Edit, although the specs might not be right. Didn't the jspec supra use CT20a (or something similar)

Great find Andy!

I agree.....sticky time

the specs might not be right. Didn't the jspec supra use CT20a (or something similar)

From what I gather, the J Spec turbos are CT20. When the CT20B was released (which is a more advanced turbo, possibly bigger too) the old one started to be called a CT20A, just to help confuse us.

When I bought my Supra, it came with an invoice for a couple of remanufactured turbos. The part number that was fitted was CT20R. The R suffix in this case seems to point to the round turbine housing inlet. Seems to be a pretty rare feature in a turbo.

Here's some other data that I found. This is probably just going to confuse the matter because the numbers don't quite match with the documents above, but it may help someone here. I forgot to note the source of the data. Chances are it was on here somewhere.

Manufacturer Toyota (Hitachi)

Type CT-20 (PN: 17201-46020 (Front), 17208-46020 (Rear)

Turbine size (Outlet diameter) 48mm

Turbine size (Inlet diameter) 59.8mm

Turbine blade count 10

Turbine material Ceramic

Turbine housing Inlet (ID) 36mm

Turbine housing Outlet (ID) 50.1mm

Turbine shaft Diameter 10mm

Turbine housing A/R .35

Compressor size (Inlet diameter) 37mm

Compressor size (Outlet diameter) 62mm

Compressor blade count 10

Compressor material Aluminium

Compressor housing Inlet (ID) 49.8mm

Compressor housing Outlet (ID) 32.4mm

Compressor housing A/R .36

*Wastegate size (ID) 26mm

Actuator spring rate 10 psi

Bearing ID 10.05mm

Bearing OD 15.9mm

Bearing width 9mm

Bearing material Bronze

Bearing oiling holes (per bearing) 6

Manufacturer Toyota (Hitachi) Export Specification (Steel Turbines)

Type CT-12B (PN: ? (Front), ? (Rear)

Turbine size (Outlet diameter) 44mm

Turbine size (Inlet diameter) 52mm

Turbine blade count 9

Turbine material Steel

Turbine housing Inlet (ID)

Turbine housing Outlet (ID) 50.1mm

Turbine shaft Diameter 7.5mm

Turbine housing A/R

Compressor size (Inlet diameter) 39mm

Compressor size (Outlet diameter) 58mm

Compressor blade count 10

Compressor material Aluminium

Compressor housing Inlet (ID) 49.8mm

Compressor housing Outlet (ID)

Compressor housing A/R

*Wastegate size (ID) 30mm

Actuator spring rate 10 psi

Bearing ID 8.53mm

Bearing OD 13.55mm

Bearing width 9mm

Bearing material Bronze

Bearing oiling holes (per bearing)

When I bought my Supra, it came with an invoice for a couple of remanufactured turbos. The part number that was fitted was CT20R. The R suffix in this case seems to point to the round turbine housing inlet.

After having a chat with the guys from Universal Turbos at Japfest (they did the fitting of my current turbos, very helpful too) it turns out that the R in CT20R simply stands for "Remanufactured". Turns out I was chatting b*****s before.