Rollers

Thanks for the info john,any reason why you would go for a vf35 over a vf34?

john banks

The VF35 is the only one I've come across that convincingly spools up better than the 16G. The rest appear to spool up similar but make less power.

Rollers

Thanks for all your help,i've got £1100 to spend on a turbo that will fit on a stock manifold of a sti v7 ra,looking for good response and power,is the 20g that one i want?

Rollers

Just thought i'd say that decent response is a little slower than a vf34.

Rollers

found this site,looks quite good but there's not many hp ratings on the turbos?
http://www.boostplanet.com/

john banks

As I posted earlier:

BVM

VF35 spools faster than the VF34 but does not make as much peak power.
18g or 20g is what you want. Trust me on that.

Hattori Hanzo

Hey Rollers,

I’ll have to go against everyone here and still recommend you the IHI turbos. Firstly you have to understand that you can’t have no lag and make big power in a small displacement turbo engine. However what you can do is that you can find the best compromise. IMO for the power you are after PE1818 (rated 420+hp or 340whp) is a bloody good turbo. Only negative sides of it are its price and the fact that IHI turbos are not rebuildable. Yes there is a chance any turbo might stuff up, but under normal conditions it should last you a long time so I don’t think rebuilding is a major issue. But of course that depends on your finances and how long you are planning on keeping the car. Sometimes it’s a good excuse to try new parts when the old ones break.
Runner up to PE1818 would be VF34 (rated at 350hp or 300 atw) because it’s a proven product that is used by many satisfied Subaru owners. When you buy one it’s kind of guaranteed that I’ll make near claimed power with the right supporting mods. If you are really worried about lag then this is the turbo for you or perhaps something even smaller.

John: What do you consider restrictive? There are examples of PE1818 making 311whp @ 19psi (USA) and 229kw @ 22psi (downunder). This turbo obviously makes good power so where is the restriction coming from? It claims to be a 400+hp 12sec turbo and it does exactly what it claims with minimal lag so I don’t see where the problem is.

My recommend to you Rollers is to do your own search and try to read some reviews on these turbos as well as checking dyno charts. I may sound a bit passionate about them only because I’m also considering these two turbos and I believe I’ve done my homework to know what I’m talking about. Check out power enterprise website. They are not your average American backyard mechanics who mix n match anything and everything and put funny names on them. Don’t forget Japanese manufacturers always underrate, whereas others seem to overrate.

Cheers,

john banks

I'm afraid I take US WHP with a pinch of salt they are so incredibly optimistic. The VF turbine wheel is also a huge restriction, I can tell from running it and measuring EGBP proxies, EGT, knock, airflow.

SecretAgentMan

I'm with JB on this one...on both VF turbos, and US horsies.

/J

john banks

Hattori, I had a VF hybrid blow up BTW. I also think the power claim for the PE1818 at 340 WHP is crazy, that is GT30 (or at least GT30/P20 hybrid) territory on some UK dynos, and if you sat the turbos side by side you would see how ridiculous it is to compare them. The only UK dyno results I've seen for the PE1818 are suggestive of similar peformance to a TD05H-16G or an MD304. I'm being kind as the compressor flow figures I saw quoted at 1 bar are lower than the 16G wheel, which is what I would call a 340 BHP turbo without fuel additives. If you get a chance to look at a VF turbine wheel and compare it even to a TD05H you will see where I am coming from I think.

Some US sources claim the VF22 will hold 25 PSI at 7000 RPM on an EJ20 ROTFLOL.

Hattori Hanzo

John, I agree with you, US dynos are very optimistic but I think the ones we have here in downunder are ok. Our dyno dynamics dynos read similar numbers across the nation when set to shootout mode. So when someone purchase a VF series turbo it’s no adventure. The power it’ll put out, the times it will run etc. are all out there. VF series turbos deliver these with ease of installation and at a reasonable price. Having said that, by no means I think IHI-VF or PE series turbos are god’s gift. I just believe they are proven to work fine for subaru engines. Mitsubishi turbos are also good, my favourite being the evo3-16g (always wanted one for my VR4). But what you’ll notice even in Mitsubishi camp is that when money is no issue people tend to go with tubular manifolds and ball bearing gt series garrett turbos.

IMO putting the two turbos side by side and checking their sizes won’t give you much idea about efficiency and flow rate of a turbo. At 1 bar TD05H-16G might have higher flow which doesn’t mean at 1.4 bar it will still outflow a PE1818. This is where efficiency range comes into play.

I’m not trying to start an argument. I’m here to learn like the rest and since I’m thinking about buying a new turbo I’m trying to get lots of info and evaluate my decision.

scooby-si

iam making 385bhp and 370lbs on a td05/6 20g at 19psi on a 2.2ltr,and pat had to stop there duye to my rods but i have plenty there to make over 400bhp easy td05/6 20g love it,

if i took it to well lane i'd make 400ish

john banks

"IMO putting the two turbos side by side and checking their sizes won’t give you much idea about efficiency and flow rate of a turbo. At 1 bar TD05H-16G might have higher flow which doesn’t mean at 1.4 bar it will still outflow a PE1818. This is where efficiency range comes into play. "

True, but putting them side by side whilst considering all the other data certainly is valid. 1 bar points are often used because compressor maps are not often available.

VF hybrids are TD05 equivalents at best. You need a Mitsubishi or Garrett turbine wheel for exciting performance. I have had the benefit of comparing VF hybrids and TD turbos on the same day on the same car and have much data on it.

BVM

I still say Mitsu turbos are the way to go. Super16g or larger. I wont be swayed by the low cost of IHI turbos. 18g will be on my scoob soon.

As far as US horsepower..... ask Patrick @ Scooby Clinic about the USDM '02 WRX that put 231.9whp and 295.7hp/285ftlbs to the crank with a TBE, up-pipe, 15.2psi (stock TD04 13t turbo) and his remap last weekend. When it comes to my WRX I dont waste time with BS parts.