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Discussion Starter · #1 ·
The VF23 is really a good turbo that has a little smaller inlet diameter than VF34 but has PZ20-H Turbine housing that is a little bigger than VF34 (PZ18-H). It also has the 6 blades like VF34 and the internal wastegate set at 8 psi. Finally, it is Roller brg and should be good for all around purpose... It can easily support up to 20 psi...

Oh~ It should not be a problem running VF23 with stock fueling system as long as you don't go beyond 15 psi until STI injector and Walbro pumps are in along with UTEC to control...

It is a good turbo and I want one. There's group buy going on for $750 shipped and I just need 4 more people to sign up.

Click Here

Dan from PA

P.S.: Unless you are planning on running beyond 20 psi, don't waste your money getting VF34. It's only advantage over VF23 is that it spooils 200 RPM faster and can boost a little over 20 psi since VF34 has smaller PZ18H housing to spooil a little faster while in has slightly larger diameter to boost beyond 20psi. But VF23 will boost slightly efficient than VF34 once max boost is reached due to it's larger turbine housing (PZ20-H same as VF22).
 

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I'm not ready for a group buy, but I'm interested. I was going to get a VF30 or VF34 but really didn't like the price I was seeing for the 34. The price on the VF23 is pretty nice. What would it's HP limits be. I need Mid-12's, and drivability, so I don't want to limit myself too much, but also don't want to spend twice the money for something I'm not going to use 100% of it's power.
 

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The VF23 has a strong midrange punch, and then falls off sharply toward the redline. The VF30/34 on the other hand deliver the power more linearly and hold it better to the redline. NONE of these turbos are good for over 20psi, which is why I'm selling my VF30 and going with a '22 for the time being.

According to TurboXS' back-to-back testing of these and other turbos, the VF30 spools significantly faster than the VF23, which was one of the slowest in the test (ahead of only the VF22, and PE1820 IIRC).

That large turbine comes with a price, as does the small compressor. The VF30/34 has a more balanced configuration IMO.

-Pace
 

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Discussion Starter · #4 ·
HP limit is around 300 -350 HP.

It should get you into high 12's without fuel change (injector and pump). To get into mid 12's you would need STI injector, PUMP, & UTEC or some sort of engine management.

Dan from PA

jmussetter said:
I'm not ready for a group buy, but I'm interested. I was going to get a VF30 or VF34 but really didn't like the price I was seeing for the 34. The price on the VF23 is pretty nice. What would it's HP limits be. I need Mid-12's, and drivability, so I don't want to limit myself too much, but also don't want to spend twice the money for something I'm not going to use 100% of it's power.
 

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Discussion Starter · #5 ·
I have to disagree that VF23 falls off sharply toward redline. I have driven my friends VF23 equipped WRX with uppipe and downpipe and the max boost comes on at 3K. He is currently running the 16 psi without engine management.

Also, the VF23 has Roller brg where VF30 has bronze brg. The VF23 has PZ20H housing that it should actually boost harder toward redline assuming that you are running below 20 psi. (Same as VF22 turbine housing) The Roller brg version of VF30 is VF34 and it only spooils 200 RPM faster than VF23.

I would like to see the TURBOXS document of how they tested the flow. I don't believe that VF23 spooils significantly slower than VF30.

On the other hand, VF22 would give you more lag than VF23 while it can boost more than 20 PSI.

Dan from PA.

pace said:
The VF23 has a strong midrange punch, and then falls off sharply toward the redline. The VF30/34 on the other hand deliver the power more linearly and hold it better to the redline. NONE of these turbos are good for over 20psi, which is why I'm selling my VF30 and going with a '22 for the time being.

According to TurboXS' back-to-back testing of these and other turbos, the VF30 spools significantly faster than the VF23, which was one of the slowest in the test (ahead of only the VF22, and PE1820 IIRC).

That large turbine comes with a price, as does the small compressor. The VF30/34 has a more balanced configuration IMO.

-Pace
 

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pace said:
The VF23 has a strong midrange punch, and then falls off sharply toward the redline.
That's not how it feels at all. It pulls hard in the midrange and then pulls really hard from 6-7K. This was when riding in one on low (~15lbs) of boost. Maybe at high boost level, when it's over spinning it drop off on the top end. I know the TXS dyno at 15lbs also keeps making power until redline.

I agree the VF34 price is rediculous. We need to get some REAL turbos out, instead of paying $1-1.5K for stock turbos. T3/T04E's can be had for $550 on GB and 20G's for a little more. Very sadening.
 

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Discussion Starter · #7 ·
Pace is thinking VF24 not VF23 IMHO!

Dan from PA
TypeC said:


That's not how it feels at all. It pulls hard in the midrange and then pulls really hard from 6-7K. This was when riding in one on low (~15lbs) of boost. Maybe at high boost level, when it's over spinning it drop off on the top end. I know the TXS dyno at 15lbs also keeps making power until redline.

I agree the VF34 price is rediculous. We need to get some REAL turbos out, instead of paying $1-1.5K for stock turbos. T3/T04E's can be had for $550 on GB and 20G's for a little more. Very sadening.
 

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No, I'm thinking VF23. However, maybe it's not a fair statement on my part because we are at high altitude and at the kinds of boost levels we are running (17-19psi) all the VF series except the '22 move out of their efficiency area and fall off at the top-end. From my experience with the VF30, and from talking extensively to other users who have run both turbos, the verdict is that the '23 cannot compete with the '30 on top. This is consistent with the turbo design and if you check out the flow charts for the '23 and '30 you will see that the '30 can flow more on the top-end than the '23. My VF30 can be felt to fall off a little as you hit the redline, so I know the same would be true if I was trying to extract the same boost levels from a VF23. This is the reason I'm moving to a VF22.

You seem to have overlooked the fact that the VF30/34 has a significantly larger compressor housing than the '23, and is a much newer design. The VF23 is fine if you have modest power goals, just like the VF30/34. I'm not saying it is a bad turbo, but you are going to have a tough time convincing anybody with first hand experience of these units that it is superior to the 30/34 in this application.

Bronze sleeve bearings are used for servicability and to some extent durability. Whether they are inferior to roller bearings depends upon your criteria. FYI, my family owns a bronze bearing plant and I have a degree in Metallurgy, so I know a little bit about bearings. ;)

Argue the spool issue with TurboXS. I will find a link to the post on I-club for you.

I agree that the VF34 was a little overpriced, but it can now be had for only around $150-$200 more than the '30.

Have you guys checked out the VF35 at all?

-Pace
 

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TypeC said:


That's not how it feels at all. It pulls hard in the midrange and then pulls really hard from 6-7K. This was when riding in one on low (~15lbs) of boost. Maybe at high boost level, when it's over spinning it drop off on the top end. I know the TXS dyno at 15lbs also keeps making power until redline.

..
TypeC; just curious if you have had a bigger turbo on your WRX? Compared to the TD04, the '23 is going to feel like a freight train to the redline. It's all relative. Fit a VF30, and your VF23 is going to feel positively asthmatic on the top end. Ditto anyone who swaps out a VF30 for a PE1818.

Dan was right all along. The 23/30/34 are teeny tiny turbos and you CAN feel them falling off on top.

-Pace
 

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Ok, I should apologise for hijacking your thread. It's just that you made some statements that vary from subjective, to questionable, to blatantly untrue. I just don't want anyone to be mislead.

It can easily support up to 20 psi.
Unless you are planning on running beyond 20 psi, don't waste your money getting VF34.
It's only advantage over VF23 is that it spooils 200 RPM faster and can boost a little over 20 psi.
1. Whether a VF34 is a waste of money is purely subjective. The price difference between a '30 and a '34 is not all that significant any more.
2. A VF23 is out of it's efficiency range in this application at 20psi.
3. A VF34 is not capable of pushing over 20psi efficiently in this application.
4. The observation that the sole advantage of the VF34 is the ability to boost a little higher and spool 200rpms quicker is subjective and oversimplistic.
5. According to TurboXS' testing, and the testimony of the users that have run both turbos, the VF34 has a spool advantage over the VF23 significantly greater than 200rpms.

-Pace
 

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Well, I already have the UniChip so that's not a problem. If I do the turbo, I will also go with injectors/pump, otherwise I would be wasting my money on the turbo!

Maybe I want a VF22 now??? hmmm.:confused:

How much MORE are you guys boosting over 20psi?!?!:eek:

I want somewhere around 275-300hp @ wheels. I know the recipie, I just can't make up my mind on the MAIN ingredient.
 

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I'd just like to get TO 20psi right now ;) We have trouble pushing any of the VF series (except the '22) over 18psi. That equates to about 20psi at sea-level.

The VF22 is apparently good to about 20psi up here.

-Pace
 

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Discussion Starter · #13 · (Edited)
Pace -

Keep in mind that your statement about VF series TURBO could also be subjective and over simplistic based on your opinion!!!!

1. If you look at the CFM map, VF23 clearly has the larger area in the MID-HIGH range over VF30. Therefore, it is more practical for all around purpose TURBO with solid mid to high range.

SR30 is very similar to VF23...
APS turbo specs - Click Here


2. I don't see how Bronze Brg based TURBO could be easier to maintenance than Roller Brg based TURBO? I do know for fact that Roller Brg based TURBO spooils faster than Non-BB turbo(Assuming that turbo has same equipment - Comp, TURBINE, wheel blade, ...etc)

3. Ask JAMA or anyone that has used VF23 as well as VF30 in Colorado area, they will confirm that VF23 performed better than VF30 around 18psi. At least this is how I was informed through the threads I read from the I-Club (Search I club using word "VF23 and VF30").

4. I agree it was "my OPINION" that spending $450 more on VF34 was waste of money. It is subjective!

5. When you choose to upgrade TURBO, I am sure everyone has their own goal. It seems to me that your emphasis are in the boosting 20 psi. I am sure that you do know that VF22's drivability is not quite well since it has the most TURBO lag in the VF series... <--- clearly it's a drag turbo like PE1820... (alright, it is MY OPINION and it could be subjective)

Well, My goal is not really on shaving lots of time/seconds in the drag strip. My car is a daily driver and I'd like to auto cross very much that I really like a turbo with solid mid-range while it can support high boost as well for occasional vist to the drag strip...

I do think that VF34 (Roller brg) would be a better choice since VF34 is somewhat in between VF23 and VF22 performance wise. However, I just can not justify $450 more for VF34 in "my opinion". Here in Pennsylvania, VF34 only spooils 200 RPM faster than VF23. The VF30 actually does not spooil faster than VF23..... Well, again this is MY OBSERVATION......

Dan from PA
 

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Discussion Starter · #14 ·
Yes, upgrading fuel system (injector & pump) would increase the safety margin if you are running above 16 psi with generally bigger aftermarket turbo than TD04....

However, runing below 16 psi with VF23 is quite safe and actually does perform well with stock fuel systems.

Click Here

Personally, I plan to stay at 15 psi until I get UTEC, injector, & fuel pump. My utimate goal is to get upto 18 psi..

Dan from PA


jmussetter said:
Well, I already have the UniChip so that's not a problem. If I do the turbo, I will also go with injectors/pump, otherwise I would be wasting my money on the turbo!

Maybe I want a VF22 now??? hmmm.:confused:

How much MORE are you guys boosting over 20psi?!?!:eek:

I want somewhere around 275-300hp @ wheels. I know the recipie, I just can't make up my mind on the MAIN ingredient.
 

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02WRX_PA said:
Pace -

Keep in mind that your statement about VF series TURBO could also be subjective and over simplistic based on your opinion!!!!

1. If you look at the CFM map, VF23 clearly has the larger area in the MID-HIGH range over VF30. Therefore, it is more practical for all around purpose TURBO with solid mid to high range.

SR30 is very similar to VF23...
APS turbo specs - Click Here


2. I don't see how Bronze Brg based TURBO could be easier to maintenance than Roller Brg based TURBO? I do know for fact that Roller Brg based TURBO spooils faster than Non-BB turbo(Assuming that turbo has same equipment - Comp, TURBINE, wheel blade, ...etc)

3. Ask JAMA or anyone that has used VF23 as well as VF30 in Colorado area, they will confirm that VF23 performed better than VF30 around 18psi. At least this is how I was informed through the threads I read from the I-Club (Search I club using word "VF23 and VF30").

4. I agree it was "my OPINION" that spending $450 more on VF34 was waste of money. It is subjective!

5. When you choose to upgrade TURBO, I am sure everyone has their own goal. It seems to me that your emphasis are in the boosting 20 psi. I am sure that you do know that VF22's drivability is not quite well since it has the most TURBO lag in the VF series... <--- clearly it's a drag turbo like PE1820... (alright, it is MY OPINION and it could be subjective)

Well, My goal is not really on shaving lots of time/seconds in the drag strip. My car is a daily driver and I'd like to auto cross very much that I really like a turbo with solid mid-range while it can support high boost as well for occasional vist to the drag strip...

I do think that VF34 (Roller brg) would be a better choice since VF34 is somewhat in between VF23 and VF22 performance wise. However, I just can not justify $450 more for VF34 in "my opinion". Here in Pennsylvania, VF34 only spooils 200 RPM faster than VF23. The VF30 actually does not spooil faster than VF23..... Well, again this is MY OBSERVATION......

Dan from PA
I totally agree on most parts.
Pace, if you read the many accounts of people who've had both the 30 and 23, they all say the 23 'feels' faster. Also, the dyno's in the 260-280whp range seem to be pretty much equal between the two. In fact, even TXS VF23 dyno continues to increase whp until redline. Now, the VF30 probably will make more top end (Imprezed test both, and made 12hp more in the last 800rpm or so, but the 23 had more low/mid power).

At anyrate, The VF22 is the big daddy of the VF world, but another factor not mentioned is reliability. I think we've all (who've been following the threads of the last yr) have seen the VF22 self-destruct rate. My friend's are running them succesfully, but others have had them blow in a month or less. MY friend's and I have a theory that this fault is due to running high boost/turbo rpms (20+psi @ high rpms) which is taking it's toll on that turbo. This is only a theory though. The people I know personally with them run under 20psi and they have lasted so far (~6 mos).

-C

btw, has anyone heard anything about the bolt on garrett kits that were supposedly in the works sinec early spring?
 

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1. If you look at the CFM map, VF23 clearly has the larger area in the MID-HIGH range over VF30. Therefore, it is more practical for all around purpose TURBO with solid mid to high range.
The VF30 spools faster and flows more on top. That's what I said. That's still true.

SR30 is very similar to VF23...
APS turbo specs - Click Here
I don't doubt it.

2. I don't see how Bronze Brg based TURBO could be easier to maintenance than Roller Brg based TURBO? I do know for fact that Roller Brg based TURBO spooils faster than Non-BB turbo(Assuming that turbo has same equipment - Comp, TURBINE, wheel blade, ...etc)
Two things. Firstly the bronze bearing is manufactured as a one piece sleeve cartridge. This makes servicing relatively trivial. Secondly, as time progresses a bronze bearing will gradually wear out which saves the shaft that is riding in the bearing, as well as the bearing housing. Roller bearings on the other hand are very tough and will pretty much destroy everything around them when they fail. Roller and ball bearings will fail catastrophically. In contrast, a bronze sleeve will gradually wear.

Both Caterpillar and Mack (truck) believe in this philosophy which is why my family's company is their sole bearing supplier.

3. Ask JAMA or anyone that has used VF23 as well as VF30 in Colorado area, they will confirm that VF23 performed better than VF30 around 18psi. At least this is how I was informed through the threads I read from the I-Club (Search I club using word "VF23 and VF30").
I have done. I'm friends with JaMa and we have talked about this in the past. The VF23 is does not have a very linear power delivery. Consequently it is punchy and feels as though it comes on hard. This doesn't detract from the fact that it falls off more on top and takes longer to spool than the VF30.

4. I agree it was "my OPINION" that spending $450 more on VF34 was waste of money. It is subjective!
I assume you are talking about the price difference between the VF23 and the VF34 (since the gap from the VF30 is much smaller). This is like comparing a VF22 to a PE1818. The turbos you are comparing have been price differentiated so that one can target a slightly more demanding audience. It flows a little more and should operate a little more efficiently. It's newer technology.

5. When you choose to upgrade TURBO, I am sure everyone has their own goal. It seems to me that your emphasis are in the boosting 20 psi. I am sure that you do know that VF22's drivability is not quite well since it has the most TURBO lag in the VF series... <--- clearly it's a drag turbo like PE1820... (alright, it is MY OPINION and it could be subjective)
Let me just remind you that it was you that brought up the 20psi number and kept throwing it out there. I was just pointing out that the VF series (excepting the 22) are not very efficient at those kinds of boost levels.

Yes.. the VF22 is the laggiest VF. Bigger turbos usually come at a compromise.

Here in Pennsylvania, VF34 only spooils 200 RPM faster than VF23. The VF30 actually does not spooil faster than VF23..... Well, again this is MY OBSERVATION......
I'm curious to know who has done back-to-back comparisons of the VF23 versus the VF34 on the same car with the same mods, in PA. This contradicts just about every user report I have read comparing these two units, including TurboXS' sea-level testing.

I'm sure that the VF23 will serve you well. Just don't mislead the members into believing it is the be all. If I have learned one thing in modifying my WRX is that the turbochargers for this application have a very narrow efficient horsepower window. You have to choose very carefully for your very specific goals.

-Pace
 

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The VF30 spools faster and flows more on top. That's what I said. That's still true.
That part isn't true. The VF34 may spool as fast or faster than a VF23 (no dyno of both that I know of), but the VF30 certainly spools slower. The only dyno of both on the same car is Imprez'd 's car which shows the 23 spooling faster (not a huge amount). The other dyno's have killer low/mid/high as well.

I think we're all on the same page, perhaps you meant the 34 spools faster?

T3/T04E 54 trim sounds good...
 

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let us not forget that the VF23 was on the legendary 22B Impreza..(0-60 monster of 4.4 sec)...there is a reason for that, that is why I have a 23. I believe the VF23 to be more of a "fun factor" turbo..it hits hard and pulls linear to redline (in my experience). I did a rolling start against WRXThis (Brian) from i-club, both in second gear.......he has the 1820, I have the 23 (obviously) I literally stomped him in the low end, he then started to gain back the ground he lost. We also did a highway run, from 60-100mph I got stomped on!! but he is running 18-19psi, as I am running 14-15psi. I agree the VF34 is still a small turbo and not worth the extra money.

Nate
 

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TypeC said:

That part isn't true. The VF34 may spool as fast or faster than a VF23 (no dyno of both that I know of), but the VF30 certainly spools slower. The only dyno of both on the same car is Imprez'd 's car which shows the 23 spooling faster (not a huge amount). The other dyno's have killer low/mid/high as well.

I think we're all on the same page, perhaps you meant the 34 spools faster?

T3/T04E 54 trim sounds good...
Yep, it was a typo on my part. I meant to say VF34. Regardless, this has been drawn out at length on 'the other forum' with people arguing the VF30 (thirty) versus VF23 spoolup on both sides of the fence. That's when TurboXS chimed in and showed their testing results demonstrating that the VF30 (yes, thirty) did in fact spool faster than the VF23, when boosting to the same levels on the similar vehicles.

-Pace
 

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From TurboXS. Phil does however point out that the cars were not identical, although they were similarly equipped. However, these numbers were extrapolated from their large database of vehicles they have dynoed, so it represents a large sampling of data and will be largely representative of the actual turbo characteristics.

Stock: 2890 (w/ catless UP)
FP: 3270
VF30: 3390
VF23: 3470
VF22: 3630
1818: 3760
1820: 3975
http://forums.i-club.com/forums/showthread.php?s=&threadid=176853&perpage=20&pagenumber=2

-Pace
 
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