• RWD

  • 1JZ 244 Single Turbo Conversion

It's been 10 years since I dropped the 1JZ into my 244, and with Christmas around the corner I thought I'd treat myself and spend a bit of money on it.

The problem:
Toyota utilise 2 x CT-12A turbochargers on the non-VVTi 1JZ-GTE engine, which run in parallel. The design of the dump pipe means that the exhausts from each turbo collide into each other before exiting to the exhaust, causing a significant restriction and power loss. The turbos also utilise ceramic exhaust wheels, which have a glass ceiling of around 14psi, after which they become unreliable (read: fly down the exhaust in many pieces).

Solutions:
  • Remove the turbos and change the ceramic exhaust wheels to steel, which will allow higher boost.
  • Purchase or fabricate a new dump pipe, designed so exhaust gases flow more freely.
  • Remove entirely the twin-turbo set up and replace with a single turbo.
In this case, the cost for steel-wheeling the turbos and fabrication of the dump pipes was too high for the potential power gain, so I opted to go the single-turbo route.

The project:
Remove both turbos, manifolds and all associated plumbing. Replace with a quality exhaust manifold, larger turbo and external wastegate. Fabricate dump pipe to suit, modify oil and water lines to suit, modify intercooler plumbing and add a catch can to replace current crank case pressure relief system. Due to budget restrictions, the set up must run with the standard Toyota ECU for the time being.

The parts:
  • Garrett GT3582R, 0.82 rear housing
  • 6BOOST steam-pipe manifold
  • Turbosmart 45mm external wastegate
  • Studs, nuts, fittings, hoses etc
Some photos are taken with my mate's ancient iPhone 4, so apologies for lack of quality.

The turbo


Exhaust manifold




Stock turbo and manifold removal






Casualties


All the parts removed


CT-12A turbos removed, a closer look. Very small wheels!




Manifold and turbo test-fit for clearance. The compressor housing will need to be rotated before final fitment.




Size comparison of CT-12A and GT3582R


Wastegate pipe welding and fitment




More to come as the work progresses...
Very nice! how will the computer handle it? Just stick in bigger injectors?

The ct 12 is used on the 2.4 diesel hilux/4 runner engine, so they do spool well.
The computer should be able to handle anything up to 16psi. I am only going to run 7psi or so for now, so it will be OK on the standard injectors for the time being. I will put bigger injectors in when I get a new ECU.

The CT12's do indeed spool very quickly, but run out of puff at around 5500-6000rpm.
11 days later
I thought this would be a much longer build thread, but the boys got right into it to get things done before Christmas, so here is my Christmas present for 2016.





I actually had a mishap on the way home from picking it up, a fuel line blew off the filter, stranding me for a short while. This was unrelated to the work done, just a very unfortunate coincidence, and I won' t be able to fix it properly till mid next week. Once I do and take it for a proper drive I'll be able to see how much of a difference the new turbo makes.
Is this the 244 from nationals last year? Come a long way. Looks much more clean and organised
blondejay;95043 wroteIs this the 244 from nationals last year?
Yeah mate I was there last year. I didn't make it to Forster this year though.

I followed your original build and was impressed then with the quality of the work and the solutions to some of the fitment issues. Always interested when too much power is never enough.

Have you had any dramas with the original conversion. I would think the Toyota motor/trans combo would be reliable, but how has the diff handled it.

Still a killer conversion and great turbo upgrade.
10 years ago today the car was in the workshop having the conversion done. I've been really impressed with the reliability of it, almost all of the Toyota and custom components have held up just fine. It hasn't been without some issues though:
  • About 7 or 8 years ago I broke the crown and pinion gears in the diff, shearing a number of teeth off them. However I'm not sure if this was due to the new power, as it was a gradual degradation leading to the failure, not a sudden thing. I replaced the gears with Yukon gears and they've been fine ever since.
  • 2 PWR aluminium radiators failed. The cause of the failures is unknown, but since then I switched to a copper/brass unit and it's been completely fine.
  • The rear main seal does not last as long as it should, not sure why.
  • I experienced very, very poor fuel economy (around 23L/100km) which was traced to ageing capacitors on the Toyota ECU. Replaced the capacitors and problem solved.
  • There are some clearance issues with the 3" tailshaft and the floorpan. Too much weight in the car causes it to rub a little.
Those were the main issues, I'd say the radiator drama was probably the worst and most costly to get sorted out. About the diff specifically, other than breaking the gears it's been fine in all other aspects.
My friends 4age kept blowing rear main seals and it was because of incorrectly plumbed PCV/breather setup
Speedy sleeve fixes worn crank rear mains.
I did have a faulty PCV valve which I replaced some years ago, which seems to have extended the life of the rear main somewhat. Now with the new turbo, the PCV set up is now plumbed to a catch can instead, so we'll see if that makes any difference.

Speedy sleeve looks like a decent idea, might look into it when it's time to change the seal next.
I should have done it on the crank for my 2L with my hilux. And may do it on my b20 if it becomes an issue.
Its interesting about the radiators. PWR charge big dollars but when I was investigating a new radiator, I wasn't impressed with the cores they used. Too narrow. Also, some of the finishing was questionable, so I went to Race Radiators and had them make one up. Best money spent.
I liked the idea of a nice, light aluminium radiator (as well as the aesthetics), but in my experience the PWR units were very fragile. A lot of people use PWR with success, so I won't slag them off, but they couldn't get it right for my application. My PWR intercooler on the other hand has been just fine.
Such a cool car @FrankCsapo can't wait to see it in the flesh again sometime!
Hopefully sooner rather than later mate, it would be good to catch up again!
Good to know bout PWR, I thought they the best, maybe lacking in QA or even stuff brought in to sell. Considered a P80 radiator but they quoted 1200 odd years ago iirc.
I will keep Race Radiators in mind.
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