A short summary of the performance gains achieved with the VF52 compared to the TD04 turbo in a Subaru vehicle. This turbo is a great upgrade if you're content with having a safe amount of power under your hood that won't hurt your engine.
For the full car engine upgrade details, please check out my post here.
Contents
Dyno Results
Stock vs VF52
+33.1% Torque (Adding 83 Nm, or 61.2 ft lb)
As can be seen in the dyno run above, from a stock factory tuned TD04, there is massive gains to be had in both power and torque when moving up to a tuned VF52 with an accompanying free flowing turbo back exhaust. Although you do lose a bit of grunt below 2700 RPM, the power that's there when you need it while accelerating at higher RPMs is significantly boosted. If you're getting an exhaust at some point, to either increase performance or just for a nice grumble - fork out the extra for a full turbo back exhaust, rather than a cat back, otherwise you won't be able to unlock the full potential of VF52 turbo with the badly designed flat plate on the stock exhaust. Although these numbers are more dramatic, they're more useful for those that haven't modified their vehicle yet, and are making plans on their potential gains.
Tuned TD04 vs VF52
+6.71% Torque (Adding 21 Nm, or 15.5 ft lb)
This is a more fairer direct comparison between the two turbos. In both these runs, the only difference is the turbo (TD04 vs VF52) and the accompanying ECU tune. At this point the only other modifications that has been installed is a full turbo back exhaust (TBE). You can see that the TD04 ECU tune on the TBE made a massive difference, but due to the limited air flow from the smaller turbo, it really runs out of grunt at the high RPM range from around 4600 RPM onwards.
An 18% power gain is significant, and it still has potential with further bolt on engine modifications. For the next steps in the upgrade, check out my build here.
Comparison Photos
Here's a few photos I took, before I installed it, to show the visual differences between the two, the slightly larger size is noticeable. The newer and cleaner one is the VF52 - fresh from the factory.
If you're reading this article, and considering a VF52 turbo upgrade from a TD04, I'd highly recommend it, zero regrets and zero issues several years down the track.
Awesome this helped me alot. Thankyou
ReplyDeleteNo worries, I'm glad you found it useful!
DeleteHi mate you still have your SH FORESTER VF52 ? wondering anywhere else I can keep intouch with you as Im about to buy me SH forester that has the VF52 tunned at 175kw from previous owner .. you on fb or insta like to ask more questions or view your forester .. video or pic ? cheers
ReplyDeleteHi James, yep I still run this Forester. it's still going well after it had been modified for close to a decade. I'm not big on social media, but feel free to ask here or on the Forester page, and I'll do my best to answer any questions.
DeleteI haven't posted any pics of my car anywhere yet, but from a visuals stand point I've only done some minor touch-ups. I've tried to keep it looking original as much as possible on the outside.
Good luck with the purchase!
Thats so good still going strong .. which forester page should I go and ask Questions ? but yeah .. May I ask how many ks/miles have you done so far with the VF52 ? have yah had any issues with the gearbox / fork /pivot ? do you recall how much you maxed on your stock injectors for your current tune ? is it worth upgrading stock intercooler for some aftermarket one ?
DeleteHello I have one question
ReplyDeleteI currently have a 2009 Forester XT in South Korea and I would like to upgrade the turbo referring to your post
Do I need ECU tuning after switching to VF52 Turbo?
Thank you!
Hi! Yes you will need ECU tuning If you're currently running the TD04 stock turbo, and upgrading to a VF52.
DeleteIf you don't mind spending time setting stuff up yourself, you can look at online tuners. But if you're not upgrading much after this, you're better off going to a local tuner to save time and get a better custom tune.
Thank you so much for your reply!! I have a COBB access port but my forester is not compatible because it's not the North America version. I'm worried because there's no Subaru professional tuner in Korea..
DeleteNo worries Ku! Sad to hear there's no specialist tuners in Korea for Subaru, but it's great that you already have a COBB Accessport though. You should be able to get a custom tune using that through an online tuner, but you'll need to have access to a decent length of private road, or dyno access, to do low gear pulls for legally refining your tune. It'll turn out much better than an off-the-shelf COBB tune!
DeleteIf you check out my main Subaru Forester upgrades post here you should be able to see some results of my custom tuning with Torqued Performance in the US. I haven't had anything done with them for years, but it looks like their website is still up. They may or may not deal with Korean cars, but you can try contacting them directly to ask about custom tuning details (don't but the off the shelf tunes as they are America and Australia only). It doesn't hurt to ask!
Thank you again for your kind reply
DeleteMy 2009 Forester XT is 4EAT (It's only one in South Korea)
I brought it from the Philippines and found that it was a model exported to Europe and other countries
Unaware of this, I purchased Grimspeed's open intake and COBB Stage 1 bundle. I paid over 1500 USD, but I couldn't use anything.. HaHa (It was later found out if only the North American and Australian versions were available)
I will ask Torqued Performance as your advice!
Thank you!!
Great information! I am planning to do the same but where can I purchase an IHI VF52 online? Would you recommend the Chine made turbos from Maxpeedingrods instead of IHI?
ReplyDeleteHi Webber, thanks! And that's awesome to hear - it's a great upgrade!
DeleteTLDR: I'd go with the genuine OEM IHI VF52.
I think there's a few places that still sell the OEM IHI VF52. You can check out the one at Pro Speed Racing here. I've purchased car parts from them before, and they have good customer service too.
I think whether you consider an OEM grade IHI turbo or not depends on your own priorities, but for me, reliability was my top priority. And as an example of a worst case scenario, broken turbo blades from a bad turbo getting into your engine can lead to very costly repairs, as well as downtime for your vehicle.
Turbochargers when under load can spin up to, and beyond, 100,000+ RPM, and they do this at crazy high temperatures. I really didn't want to risk a failure point with my turbo, so I went with the IHI VF52, identical to the turbos used in Subaru WRX models at the time, on the same engine model. It was a case of going with the tried and true, but then tuning it a bit higher than from the factory.
I think regardless of what turbo you get, make sure you find a good Tuner (local or remote e-tuner) that will be happy to help you tune it properly, and not use an off the shelf solution. A custom tune will probably be more predictable with the known IHI VF52, while any manufacturing variances in other versions might be discovered during this process.