VF40 vs TD04L-19T on 2005 XT

[ZachCouch]

I just discovered I have the wrong turbo in my XT (2005). A friend of mine sent me a CL ad of a Legacy GT he's looking at. One of the pics in the ad is of the new turbo which was installed, another VF40. Well, this is the first time I've ever had a good look at a VF40 out in the open. And I noticed it's not quite the same as the turbo in my '05 XT. So I went outside and popped my hood to look. Lo and behold, it's not a VF40. It's a TD04L-19T for a 2008 WRX. I knew the dealer had replaced the turbo, intercooler, and oil lines before I bought it, but I assumed they had replaced it with another VF40. Apparently not.

 

I've been running an Accessport for the past few months with Cobb's S1 tune. I've had perfect fuel trims and boost levels on my datalogs. It's giving me good numbers, and the butt dyno feels great. Nothing that would point me towards thinking I didn't have the correct turbo. Given that, what should I do about this? Should I even do anything about it? How can I confirm it's a genuine MHI turbo and not a knockoff copy? How does a 19T compare to a VF40, both in reliability and capability? I guess what I'm wondering is whether or not I'd see any appreciable gains by switching back to a VF40.

 

Thanks for any info, guys.

[relative4]

I've been told by a very knowledgeable source that the TD04 is a slight downgrade from the VF40. You're not in serious danger with the current setup, but they do have different spool, spring rate, and load, so if you keep the TD04 you should get tuned for it.

I agree with your expectation that the proper path is to get a VF40.

[ZachCouch]

I've been told by a very knowledgeable source that the TD04 is a slight downgrade from the VF40. You're not in serious danger with the current setup, but they do have different spool, spring rate, and load, so if you keep the TD04 you should get tuned for it.

I agree with your expectation that the proper path is to get a VF40.

 

Downgrade in what regard? Power potential? And would you consider the TD04-19T an unhealthy restriction to the EJ255, or a viable option for shifting the powerband down and increasing low-end performance? The redneck in me wants BIG NUMBERS TO FLEX ON EVERYBODY. But the reality is that when driving spiritedly, I spend most of my time around 2500-4000 rpms cruising backroads, or around 2000 rpms offroading. Would the VF40 be any better suited to this than the TD04? I'm just trying to weigh all my options before I start spending money again.

[GEE-OTTO]

TD04 would have been on a pre-08 WRX, 08 would have been VF52. Depending on the dealer I wouldn't be shocked if the car has been put back together and trader/sold. Also wouldn't be shocked if that isn't a Ej25 but a JDM EJ20 that can be had for under $2k complete.

[mondtster]

TD04 would have been on a pre-08 WRX, 08 would have been VF52. Depending on the dealer I wouldn't be shocked if the car has been put back together and trader/sold. Also wouldn't be shocked if that isn't a Ej25 but a JDM EJ20 that can be had for under $2k complete.

 

One would think he'd know if the parts were off a pre 2008 WRX because the differences should be apparent. Further, I don't think those turbos were 19Ts? I haven't seen one for a while, can't remember what they were.

 

I agree it could be an EJ20Y someone swapped in there. They had the 19Ts on them. Or, it could be just a hot side and intercooler swap onto an EJ25.

 

I think the OP should take a picture of the engine compartment with the engine cover removed. There are some signs that might help determine what he has.

 

As a side note, it is my opinion that the 19T is a better turbo than the VF40. But I'd view them as equal when it comes to the power capability department.

[ZachCouch]

The 2002-2007 WRX had the TD04L-13T, then in 2008 they switched to a TD04L-19T for one year. In 2009 they switched again to the VF52, which they used all the way until the switch to the FA20DIT with a Garrett twinscroll in 2014. This is covered in detail in the official list of Subaru OEM turbos on NASIOC. Mind, these are the USDM OEM turbos.

 

It's not an EJ20, JDM or otherwise. I've replaced enough parts in/ on it to know it's a USDM V1 EJ255.

[relative4]

Downgrade in what regard? Power potential? And would you consider the TD04-19T an unhealthy restriction to the EJ255, or a viable option for shifting the powerband down and increasing low-end performance? The redneck in me wants BIG NUMBERS TO FLEX ON EVERYBODY. But the reality is that when driving spiritedly, I spend most of my time around 2500-4000 rpms cruising backroads, or around 2000 rpms offroading. Would the VF40 be any better suited to this than the TD04? I'm just trying to weigh all my options before I start spending money again.

 

Good questions for a tuner. I heartily recommend

http://www.cryotuneperformance.com/

[GEE-OTTO]

The 2002-2007 WRX had the TD04L-13T, then in 2008 they switched to a TD04L-19T for one year. In 2009 they switched again to the VF52, which they used all the way until the switch to the FA20DIT with a Garrett twinscroll in 2014. This is covered in detail in the official list of Subaru OEM turbos on NASIOC. Mind, these are the USDM OEM turbos.

 

It's not an EJ20, JDM or otherwise. I've replaced enough parts in/ on it to know it's a USDM V1 EJ255.

 

 

Well that's good as far as the turbo are you going to swap in a VF40/46 or stick with the TD04? If it runs strong and is otherwise reliable I'd ride it out and maybe keep your eye on the forums for a low mileage spare turbo

[ZachCouch]

Well that's good as far as the turbo are you going to swap in a VF40/46 or stick with the TD04? If it runs strong and is otherwise reliable I'd ride it out and maybe keep your eye on the forums for a low mileage spare turbo

 

I like the way it pulls, I'm getting good fuel trims, and I'm hitting target boost. So I think I'm gonna stick the the TD04 for the time being. One day this will become a full-time project car, and I'll probably swap turbos then. Might just rebuild this one, but with an H or HL hot side.