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Hi all , I am chasing a few avenues to see if I can come up with enough in the way of VF12 parts to get 1 good one .
People tell me that they boost freely and easily on Lib RS's and I'm hoping that with decent headers and exhaust it may work well for my soon to be finished rebuilt Spider Vortex EA82T engine .
A couple of things I'd like to know are what is the std waste gate setting on early RS Turbos and is their rated power output around 142-147 Kw (190 Hp) .

I have a few mobs that used to do good one off turbo assemblies and I'm gonna press them to see if its possible to cobble together a hybrid ball bearing center section . It's a long shot but if it came off it could be a pretty good thing on a fresh uncorked EA82T and if 170 odd Hp could be coaxed out of it Ellie should have good performance in its 1070 odd Kg's shell .

The more I look at early Lib RS parts the more they seem to fit the power output I want and if the parts are reasonably cheap and easy to come by .....

Cheers A .

One day u might even realize how much easier and better it would be to use an RS engine too EJ20 FTW!!

But for the grandpa EA, maybe you should look at the TD04 turbo. Pretty similar in size and power output to the old VF12's but with newer technology they spool up a lot quicker. You can buy them brand new from Subaru. Also they are very commonly sold by people upgrading turbos on their near-new WRX's. I frequently see them forsale for well under 500 bucks with less than 15,000kms on them.

Yeah i agree!

Why bother building a outdated turbo when there is a perfectly good turbo that is still being produced and is easy to come by

If you want it to start making boost from 1800rpm and have 7psi by 2200 rpm (thats on a basically standard engine/headers setup), go the TF035. Dont forget the GT Forester is good for about 136kW, which is getting close to the upper limits of an EA82


If you want a bit more top end, go the TD04. Either way you will have a modern turbo that is easy to replace if something goes wrong. Also the TF035, TD04 and TD05 (plus many more of the VF series) are all interchangeable.

Lost two long posts here so the very short version .

VF12's have a lower blade count than later IHI and Mitsubishi turbos and reasonably big A/R ratio housings as well . They look to have been designed as a high volume low pressure turbo rather than the other way around .
TF035's and TD04's are a bit like the second example so not what I'm looking for .

If you start out with an EJ type turbo mounting flange and dump flange on an EA these VF8/10/11/12 turbos virtually fall in . Once the air inlet is made vertical like an EA's native turbo they literally do .

Like I keep saying the EA82T's header is very small in the double layered sections like possibly a bit over an inch bore in places . I have not been able to measure an RS's crossover or up pipe yet but I think its pretty obvious that the difference will be more than the 10% capacity difference between an EA82 and an EJ20 . To compare an RS and a turbo Vortex down pipe/cat pipe you find a massive difference . They both look to be about 60mm at the turbo outlet flange and while the RS pipes stay the same approximate diameter over the full length the EA one is possibly 2/3 or less that size over most of its length .
I think its largely things like this (and the WAIC and the higher CR) that give the early EJ20 RS spec engine 145 odd kw and the feature starved EA RX about 75 . To me it doesn't add up that the capacity difference is 10% and the power difference a bit less than double .

Like I mentioned before Stu wilkins said that the best rally spec RX EA82T's cranked out a fragile 190 hp with the mandated std header and the garden variety read agriciltural L series MPFI inlet manifold , and NO form of IC .
I don't have to abide by rally regs so on with the ported spider/heads/NA cams/higher CR/much better header WAIC and if I can achieve it a turbo designed to support 190 Hp then the potential is all there .

Cheers A .