Port & Polish vs Upgraded Turbo

**younoleit** · 12-20-2012 01:06 PM

I'm looking to take a step up in power after I get a DP along with PW TMIC and would like to plan ahead. I'd like to maintain my 2011 WRX 4D as a daily driver. While browsing Grimmspeed I began to read reviews on their PnP turbo services while looking at getting a new, slightly larger than stock turbo. Does anyone have experience with PnP? Would I be better off going with PnP over a new turbo to avoid all of the necessary supporting upgrades and possible decrease in the life of my car? I know PnP will come nowhere close to the same power gains as a new blower, but the money and stress saved might be worth it if some performance gain is realized along with a quicker spool time.

**Mikie13** · 12-20-2012 01:14 PM

I'm sure it has some merit, otherwise they wouldn't be offering it. I don't think it's a matter of really adding much power, as it is with power delivery. You're more likely going to see some better spool as well as smoother power delivery, as opposed to more power.

If you would like to maintain something relatively stockish for a good price, look into Blouch's 19T wheel upgrade.

Also...biggest concern, what are your tuning plans? That's going to play the biggest role here.

**younoleit** · 12-20-2012 01:40 PM

Originally Posted by Mikie13

If you would like to maintain something relatively stockish for a good price, look into Blouch's 19T wheel upgrade.

Is this an entire turbo upgrade or just one side of it?
I currently have a TP Stage 1. With the DP I'd grab a TP Stage 2, but add TMIC, EBCS, and turbo upgrade at once with a protune.

**zax** · 12-20-2012 02:02 PM

Originally Posted by younoleit

Would I be better off going with PnP over a new turbo to avoid all of the necessary supporting upgrades and possible decrease in the life of my car?

I'm confused by this statement. Supporting mods are necessary when increasing power in general, not just because of an upgrade to the turbo. A motor simply moves air. That's it's primary function; air in, air out. The constituents of the air are changed, but that's besides the point. For example, if you PnP a turbo, you will effectively increase the flow capability of that turbo. That means that you will increase the volumetric efficiency moving more air through the motor. Moving more air requires more fuel for combustion at optimal AFRs. This is the case for ANY increase in VE whether it be from PnP or a larger compressor. However, increasing the flow through turbo will push you closer to edge of the compressor efficiency.

**Mikie13** · 12-20-2012 02:45 PM

Originally Posted by younoleit

Is this an entire turbo upgrade or just one side of it?
I currently have a TP Stage 1. With the DP I'd grab a TP Stage 2, but add TMIC, EBCS, and turbo upgrade at once with a protune.

It's an upgrade to the compressor wheel of the turbo.

But Zach is right...if you're planning on upgrading anything to move more air, you'll need to make sure that you have adequate fuel being delivered as well. Best thing to do would be put out your suggestions to whomever is going to be doing the tuning, and find out his thoughts. A lot of tuners prefer certain parts to their abilities.

**EJ257** · 12-20-2012 06:04 PM

I wouldn't bother

**SD_GR** · 12-20-2012 06:31 PM

One good reason to port and polish is if one is constricted by class rules in competition to use the stock unit. Check that the rules allow pnp turbos first though.

**MainFrame** · 12-20-2012 06:32 PM

Originally Posted by EJ257

I wouldn't bother

+1

I don't have any first hand experience, but from what I've read and been told, PnP turbo isn't worth it (there aren't much gains to be had, and more often than not it actually degrades performance).

**Donkey** · 12-20-2012 07:11 PM

Originally Posted by Mikie13

If you would like to maintain something relatively stockish for a good price, look into Blouch's 19T wheel upgrade.

The 2011 WRX comes with a VF52.

A good P&P job can effectively shift the powerband to the left and up.

**younoleit** · 12-20-2012 11:16 PM

Originally Posted by Mikie13

It's an upgrade to the compressor wheel of the turbo.

So I will not need an entirely new turbo? Sorry, I am not the most knowledgeable when it comes to these things. Would I really need new injectors for the PnP, or in the case, the upgraded wheel?

**teflon_jones** · 12-21-2012 12:08 AM

No, a compressor side upgrade means you're just upgrading that one side of your existing turbo. And no you won't need new injectors for a PnP (or any other fuel system hardware changes). You would want to get a new map for the car, but you'll want a new map even if you made zero other changes since the stock map leaves a lot of power on the table.

**Donkey** · 12-21-2012 05:08 AM

There is no need to upgrade the compressor considering the VF52 is larger than the 19T wheel. You would be going backwards........................not to mention the 19T upgrade is only for the Mitsubishi TD04,not any IHI turbo.

**younoleit** · 12-21-2012 08:31 AM

Ok, so the general consensus is that the only benefit I'd get from PnP is decreased spool time and shifting Power/Tq curves to the left but I wouldn't have to get any expensive supporting upgrades. If I were to take a step in turbo size, what model(s) should I look at?

**Mikie13** · 12-21-2012 09:20 AM

Originally Posted by Donkey

There is no need to upgrade the compressor considering the VF52 is larger than the 19T wheel. You would be going backwards........................not to mention the 19T upgrade is only for the Mitsubishi TD04,not any IHI turbo.

Ah didn't think about that part of it...should have mentioned the TD04 part as well. My bad