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VF48 vs 18G vs 20G vs VF52 vs DOM3

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154K views 48 replies 21 participants last post by  Karlot  
#1 · (Edited)
Did a turbo swap over the weekend and took some pics of the stock VF48 vs some Blouch turbo's. I am using the 18G and a friend is using the 20G. Should be good times for both of us. Enjoy!

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Heres a quick compare of the VF48 Stage 2 setup on E85 vs the 20G so far.

20G (Red) vs VF48 (Blue) Boost Onset and Taper
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20G Boost + AFR on E85 (95% IDC on 850cc Injectors)
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20G (Red) vs VF48 (Blue) MAF Flow
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As you can see, you suffer a little low end spool but make up for it greatly at the top! 18G results will be coming next month.

*Update - 18G with EWG is being installed this weekend (3-29-09)*
*Update - 20G setup is getting an EWG in the next few weeks as well*

Other comparisons attached below (VF52 from an 09 WRX)

VF52 vs 18G

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VF52 vs Dominator 3.0R

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#4 ·
Re: VF48 vs 18G vs 20G

I would pick the 20G as a best bang since the 18G is only like $50 less. I got mine used for super cheap so I'm going with the 18G. Both are a good gain over the stock turbo. I will have more data available as we begin tuning in a week or so. I will be doing my 18G install in a few weeks.
 
#9 ·
Re: VF48 vs 18G vs 20G

burnstacp said:
I really want to see the numbers on the 20g along with his mod list since mine will be going on in about a week and a half. I'm very curious to see how it will perform since I have had a hard time finding plots or feedback from guys that have them.
Click to expand...
Mod list on both cars:

Invidia Catted Downpipe
K&N Panel Filter
Walbro 255lph Pump
Deatchwerks 850cc Injectors
Blouch TD05H-20G-8cm2
XPT E85 Road Tune

Invidia Catless Downpipe
Invidia Up-pipe
K&N Panel Filter
Walbro 255lph Pump
Deatchwerks 850cc Injectors
Blouch TD05H-18G-8cm2
XPT E85 Road Tune
 
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#11 ·
Re: VF48 vs 18G vs 20G

I have suspected the turbine of the VF48 was plugging things up limiting the power output much more than the compressor.
Looking at the VF48 and the 18G turbines I can see why the Gs would flow better.

Almost seems like the hybrid VF48/20G would be worse. A big wheel would be slower to spool and the small turbine would choke off the top end. The 20-30 HP gain is probably from the waste gate openning more and reducing the exhaust back pressure. I guess.

I noticed that Blouch ports the turbine housing when they do their hybrid I now see why.
 
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#13 ·
Re: VF48 vs 18G vs 20G

Interested in the numbers from the 18g. Been running one on my 06 for over a year with alot of supporting mods and like it alot. Full spool before 3k and 24psi with meth, headers, UP, catless TBE, TGV deletes, etc. makes for some good fun.
 
#14 ·
Re: VF48 vs 18G vs 20G

Nice Braden. I wish there was an E85 station near Leander. My methanol tank gets emptied by the time I get home from work. Kinda annoying having to refill and refill it. I should get some 5 gallon tank or something.
 
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#29 ·
Re: VF48 vs 18G vs 20G

XPT Tuning said:
Forgot the last 2 pics, added up top. Gabe I have a 5gal Meth jug left if you want $40.
Click to expand...
Have not checked this thread in awhile. I got one from RallyDave for 20 bucks. ;)
 
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#16 ·
Re: VF48 vs 18G vs 20G

Did IHI resolved the issue with the VF wastegate housing cracking? SOME VF-39 and 43's had this issue, which would make me shy away from anything IHI makes.

Just for my curiousity, I was looking up alternatives to the VF-39 for someone who just has a simple stage 2 and isn't looking for more power.

I came up with the following: APS SS45 (45 lbs/min) and Blouche Dominator 1.

Any opinions? Again, my VF39 is doing fine, I'm just curious about this stuff.
 
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#24 ·
Re: VF48 vs 18G vs 20G

Peleg said:
Did IHI resolved the issue with the VF wastegate housing cracking? SOME VF-39 and 43's had this issue, which would make me shy away from anything IHI makes.

Just for my curiousity, I was looking up alternatives to the VF-39 for someone who just has a simple stage 2 and isn't looking for more power.

I came up with the following: APS SS45 (45 lbs/min) and Blouche Dominator 1.

Any opinions? Again, my VF39 is doing fine, I'm just curious about this stuff.
Click to expand...
the two turbos you mention are way bigger than the stock vf39 ;) the dominator1 is about the size of an FPgreen ;)

if you are happy with stage2 power, and your vf39 dies; get a vf34 ... or for slightly more power, a 16G.


J.
 
#17 ·
Re: VF48 vs 18G vs 20G

No cracking on this one here, not sure if it would develop down the road or not. It's a solid turbo. I would skip the SS45 and just go with a Blouch TD05H-20G-8cm2 since it's got great spool and top end. I got a spin in it today at wastegate boost (14psi) and it picks up quick!
 
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#20 ·
Re: VF48 vs 18G vs 20G

XPT Tuning said:
No cracking on this one here, not sure if it would develop down the road or not. It's a solid turbo. I would skip the SS45 and just go with a Blouch TD05H-20G-8cm2 since it's got great spool and top end. I got a spin in it today at wastegate boost (14psi) and it picks up quick!
Click to expand...
Thanks for providing this information.

Curious how the Blouch TD05H-20G-8cm2 would compare to Blouch TD06H-20G-7cm2

On my legacy I had a vf34 then, TD06H-18G-7cm2, and later went 8cm2(yeah baby steps).
vf34 --> TD06H-18G-7cm2 ==meh, big loss of spool, not much reward.
I lated added a prodrive solenoid and retune => :) Brought back much of the spool and stronger mid range (more boost). Happy again

TD06H-18G-7cm2 --> TD06H-18G-8cm2 == :confused:
big loss of spool, some more top end

TD06H-18G-8cm2 ==> 2.5R :D

I didn't think the 8cm housing was worth it on the 18g. I thought it spool a good bit slower without much reward of topend (on an 18g). I later went Dominator 2.5R w/8cm housing and thought it spooled
"about" the same as the TD06H-18G-8cm2 with a huge reward in topend.
 
#21 ·
Re: VF48 vs 18G vs 20G

burnstacp said:
Excellent! Thanks for the info. Is your buddy going to do anything to try to make it spool up faster (EL headers...)?
Click to expand...
Once we've got the boost stabilized at 22psi I will start by adding more % to the ramp up before boost hits. This may net a 100-300rpm spool increase but I'm really not hopeful that it will get much better than this here. Keep in mind this is also in 3rd gear so 4th will drop a few hundred as well.

I think the only things that may help beyond that would be an Up-Pipe, MBC Hybrid or EWG, all of which we probably won't be doing on his car. I will be doing an up-pipe when my 18G goes on so we'll see if that helps out.
 
#22 ·
Re: VF48 vs 18G vs 20G

Another update to the original post. We are now up to 22psi and you can see the VF48 and 20G both hit 22psi at roughly the same point. The only difference is that the VF48 gives you a little bit more flow under 3500 and then starts losing it quickly. The 20G takes over and continues to hold boost towards redline. We believe on the IWG and stock boost solenoid it'll hold 19.5-20psi at redline.
 
#30 ·
Re: VF48 vs 18G vs 20G

XPT Tuning said:
Another update to the original post. We are now up to 22psi and you can see the VF48 and 20G both hit 22psi at roughly the same point. The only difference is that the VF48 gives you a little bit more flow under 3500 and then starts losing it quickly. The 20G takes over and continues to hold boost towards redline. We believe on the IWG and stock boost solenoid it'll hold 19.5-20psi at redline.
Click to expand...
I am at 19 at redline on my 20G but using a 3 port. I could push it further, but at 20 PSI airflow started to dropoff. 19 PSI seemed to be the sweet spot on my car. The VF43 would do 17 at redline. I peak the 20G at 22 PSI.

Why is it that our boost curves usually look the same? ;)
 
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#32 ·
Re: VF48 vs 18G vs 20G

We haven't put my 18G in yet, still waiting on parts from Perrin before I toss it in. The only time I've had trouble with a Blouch was with the Dom3 and an APS TMIC, there is VERY little clearance between the turbo to TMIC elbow on that thing. I've also purchased an aftermarket 90 degree elbow for the turbo to TMIC as they don't fit the factory hose 85% of the time.

On the 20G we were able to re-use the factory hose but it was a tight fit.
 
#34 ·
Re: VF48 vs 18G vs 20G

sutter2k said:
What happened to the images on the first page?
Click to expand...
Sorry about that, fixing them now. I had moved my web server and the links are a little different now. I'm going to also be adding pics of the VF52 (09 WRX) next to my 18G and soon next to the VF48 coming out this weekend!
 
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