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Fuel pump, injectors, TGV deletes and TD04 19T

53K views 173 replies 24 participants last post by  Sasquatch 
#1 · (Edited)
The deletes will arrive next week. :)

I'm on the fence about a mild turbo upgrade (TD04 w/ 19T wheel). Should I?

7/14: I did. :p



Arrived 7/7: :D






7/14: :p




 
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#4 ·
I'm pretty much there now - check out my Mods & Pics link in my sig.

The turbo side TGV sensor has been intermittently throwing CELs since I did a Deadbolt Monster TD04 turbo swap 3 years ago. Access to that sensor is all but impossible without removing the intake manifold. Adding the deletes will take care of that. The stock injectors are at the ragged maximum when the weather gets cold, so in go the injectors and pump. Access to the turbo will be far easier with the manifold off ... to 19T or not to 19T?
 
#9 ·
Maybe it comes down to the amount of air it moves during a given amount of time...

All I have to say there has to be some merit to it because my VF43 boosting at 21psi was incredibly slower and less powerful than my buddy's 20g boosting at 21psi...

But Bill, the way I see it...if you have the fuel upgrades, you already have the prereqs to upgrade the turbo. May as well make use of it so long as you have the means to. The 19T or a 16G both seem like viable options. Ask what your tuner may suggest as well because I don't need to tell you that a good protune will be necessary.
 
#10 ·
it's cooler.

But you're right - at a FIXED rpm, pressure = pressure. The difference comes in the top end.

Sasquatch: I think you'd be happy with a 16g, or a vf34 or similar... or even better - go nuts, go equal length manifold, and throw on a vf36!
 
#11 ·
Are you still running SCCA events? Look closely at the existing rules for the class you are in and try to get an idea of what changes people might have in mind. If you go every other weekend so to speak you may not like where a turbo will land you, or it may change your schedule (first class, last class, get up earlier, leave later etc.) so consider that.

See if you can figure out what new cars are coming out and where they might be classed, it might give you an idea of what's in store for your existing or new-turbo-upgrade class. The newsletters are decent info sources too, especially the correspondence since people ask questions like this all the time.
 
#27 · (Edited)
Damn ... this thread took off! :eek3:

I was also thinking about a Blouch TD05H-16G. I will not go any bigger than that.

The pump is in. I was pleasantly surprised how clean the pump assembly was when it first came out of the tank.





My previous mods already put me in SM. I have not been out this year and only did 1 event last year. The WRX is over 7 years old now - I want to be more kind to it as it approaches middle age. I plan on autoxing some more, just not nearly every event like I did in 2006 - 08.
 
#20 ·
jd92677 said:
Like I said I don't race so I'm below 3k (ok maybe 4k) rpm about 80% of the time.
You have the VF52; with a TD04, you might achieve a higher PSI at a given RPM, but you'd be producing less power. Same logic.
 
#22 ·
So all things being equal, a td04 at 20psi will produce less power than a vf52 at 20psi?

Even so. You really need to drive a Wrx or Sti w/a turbo upgrade and you will be amazed at the difference in power. I used to think just like you, then I drove my friend's '04 WRX with an EVo3 16g and was amazed at how much better it was at any RPM than my stage 2 '05 Wrx. Now that I have a hybrid swap/2.5L w/18g my buddy is amazed at how much faster my car is at any point in the powerband.
My car is too fast already, but I believe you on that
 
#33 ·
I was looking into 16g's, but I realized that there's a pretty big line of IHI offerings that seems to spool quicker and give a little more top end - even discounting the twin-scroll lineup. Seriously, if you can find a vf36, DO EET!!!!
 
#34 · (Edited)
No IHI turbo I know of will have a better top end then a 16g, single scroll for sure don't. IHI turbos are not easily rebuildable or not rebuildable at all. Also, if you go twin scroll you will have to get a twin scroll manifold which can get expensive. For ease of upgrade a 16g is a much better option for most than a twin scroll. IHI/VF series turbos are just not that good IMHO.

I suggest you do more research.
 
#36 ·
On the topic of cfm/psi/etc....

I understand your thought of how a certain pressure should produce the same amount of air crammed into the cylinder. It's not correct though.

It's all about several factors, but specifically efficiency. A small turbine (td04) is efficient in the lower RPMs because of the vane shape, and it gets matched to the amount of exhaust gas that is coming out of the engine. A larger turbine (td06) will match better and be more efficient with an engine that is putting out more exhaust gas. That's why you can run a bigger turbo with a similar spool on a larger displacement engine vs a smaller engine.

On the compressor side of the turbo, you have a very similar thing happening. We aren't as concerned about PSI as much as we are flow. Pressure is read at the end of the compressor nozzle. If a turbo with the same amount of CFM's at the same engine RPM on the same engine displacement is on a car with a PNP intake manifold, and TGV deletes you'll still be flowing the same amount into the engine and get similar power. Therefore the turbo is able to run with the same CFM at a lower PSI. That efficiency translates in the ability to raise the PSI and gain additional CFM.

CFM produces power. PSI doesn't. Additional PSI will produce CFM... to a point. At some point the turbo isn't able to compress the air as efficiently and that's where you start to lose CFM. On the same note, a turbo that's efficiency is in the higher PSI range that's only producing a low amount of PSI won't be able to function as well, and won't produce power as easily, and may actually hinder your power. It isn't linear though, and it depends fully on the CFM's each of those turbos is able to produce at specific boost levels.

The numbers you see on websites (ie 450cfm @20PSI) is actually the amount of air that is being pushed out of the turbo at a given PSI. It's not how much air is able to reach the engine. That's why TGV deletes are such a great upgrade... You may only be getting 400cfm at the heads due to restrictions throughout the post turbo intake system... but when you start removing obstructions/restrictions like the TGV butterfly valve, you start allowing that turbo to "breathe easier" meaning flow more at the end point... (ie 410cfm) All of these numbers are made up though. I don't have any air metering device :D

None of this discussion has included anything about heat. Heat completely adds a whole new component to the ball game regarding PSI and flow characteristics. I'm not going to go into it though... I've already typed entirely too much.

If any of this made sense, I'm glad. If not, feel free to PM me or we can start a full blown thread regarding this. I love physics if you can't tell.
 
#40 ·
I totally understand that this happens, but I'm still completely lost as to why...

I'm trying to think on a small scale for this - you're at a (theoretical) point in the cycle of your engine at which no intake valves are open (but one is about to). The turbo has filled the intake system full of enough air that it is at a certain absolute pressure - let's say 1 bar relative, so about 29psi total pressure on the intake manifold. Currently, that cylinder that's about to open is nearing TDC, so it's losing nearly all of its volume (although you'd still expect the pressure to be somewhere close to 1 bar). The intake valve opens, and the piston begins its descent down towards BDC. you've got an initial influx of air from the pressurized manifold, as well as more air coming in as the open cylinder area expands. The amount of air going in is characterized by the force on the opening (which is the difference of the pressure in the intake and the pressure in the cylinder), which, because of how pressure works, is dependent only on pressure, because at this point pressure is pressure.

The only way this makes sense in my head is if a better flowing turbo can better keep the pressure up to its pre-valve-opening status (as in, the pressure's going to drop over the course of an intake stroke, a bigger turbo is better able to make up for this), but even that's not 100% convincing...

Can anyone give a better explanation (preferribly the correct explanation)?
 
#48 ·
From my understanding a big turbo with its big housing will need to flow more air than a smaller turbo to sustain a certain boost pressure.

Pounds per square inch..... The larger cross sectional area of the bigger turbine housing requires more air flow to sustain a given pressure than a small turbine housing.

Think of it terms of water for example, a very small hose, say the size of a straw wont need as much water flow to achieve a certain pressure as a garden hose.

So a td04 sustaining 18psi is not moving as much air per unit time as a larger turbo, whatever it may be. So 18 psi is not equivalent in every turbo. To think that is just silly.
 
#49 ·
Naturally - but boost is measured in the intake manifold (which is constant, whatever your turbo), not inside the turbo. For flow to happen, you need a source and a sink - it just doesn't make sense that changing the source, without changing the sink, changes the sink somehow :/
 
#50 · (Edited)
I don't see what the problem is. The intercooler, intake and manifold, I think, will generally be able to flow pretty well. So I think the real variable is the turbo. If you are providing more air per unit time with a better/bigger turbo more air will flow through the rest of the air tract. It's not as if the rest of the intake system is maxed out by a td04 at 20psi. So more air from turbo means more air for everything. The engine is consuming more air at that point.
 
#56 ·
eerk, it's still not making sense.

Let's just say for a minute that your turbo is compressing a totally sealed box (or, somehow, your turbo is working, but your intake valves are all closed for some reason). at 38psia, and a fixed temperature, PV=nRT - you can't escape that - this means that you'll get a fixed mass of air, no matter what's compressing it.

No obviously, the case is different, since there's flow, but it seems like this is a good approximation, until the intake valve opens. At that point, the pressure difference (multiplied by the area open) causes a force, that can accelerate a certain mass of air (fixed volume, no matter what, unless the temperature is different, etc.) through the hole.

Where does the airflow capability come into this (unless MAP drops significantly every intake stroke ???)
 
#58 ·
A sealed box is not a good approximation of a flow path. The air is going into the engine. A bigger turbo at 18 psi puts more air into the engine than a smaller turbo at 18psi. You are over thinking it. You are not taking into account that the engine is consuming the extra air.
 
#61 ·
nono, I'm talking, you have a small turbo, you swap out for a big turbo, what about being able to flow more air out the turbo makes your engine want to take in more air? This is the link I can't visualize in my head...
 
#69 ·
Buy the XT. If you don't... You'll be driving it for years thinking, "Ugh, I should have just spent the $255 years ago and enjoyed it since."

It's not a perfect thought train, but has it's merits ;)
 
#70 · (Edited)
I just spoke with Blouch in great detail about the three contenders for my turbo swap. The winner is ...

The 19T upgrade. Unless I radically change the way I drive the WRX it really is the best choice. I have had the WRX for over 7 years now and know what I want out of it.

Both 16Gs will have way more top end that I will really ever use or need. I'm told the non-XT 16G starts to spool up at 3500 to 3900 rpm. I know I will not be happy with that. The XT will be even worse. Yes, I know I will have the fuel capacity for a lot more turbo. I'd also like to keep my stock internals intact for a while.

I was told the maximum flow rate is 480 cfm for the 19T and the 16G would be 510 - 515. Those figures are right from the builder of both turbos.

There is this discussion as well that seems to indicate great things about the 19T: TD04 19T Upgrade Discussion - NASIOC
 
#72 · (Edited)
Both 16Gs will have way more top end that I will really ever use or need. I'm told the non-XT 16G starts to spool up at 3500 to 3900 rpm. I know I will not be happy with that. The XT will be even worse. Yes, I know I will have the fuel capacity for a lot more turbo. I'd also like to keep my stock internals intact for a while.
I'm just curious what they are referencing too. My 16G-XT in third gear will hit 20+psi by around 3600-3700rpm. A normal 16G can do that around 3200-3300rpm. 19T will still be a fun turbo!
 
#71 ·
Haven't read much about the 19T. I'm sure it'll be a nice boost compared to the stock one though =). Let us know your impressions of it.
 
#77 ·
arent the tgv deletes good for 1-200 rpm faster spool?
my 16g is barely past 3000rpm(3100-3200) when it hits 21 psi... did a road dyno the other day at 19.5 psi and hit 293 whp with 279tq, I'm sure it would have been much lower on a real dyno but the torque curve is awesome it shoots up and stays there nice and flat and theres barely any drop in hp at redline... floor it at 3k and theres no lag

i messed with a p&p'd td-04 for a while and i'm glad i did cause it was fun, but i dont miss the little bit more power it had down low
i contemplated a 19t upgrade with a td-04hl wheel but the cost was more than a brand new 16g due to the machining of the housings so i scraped the idea
 
#80 ·
My tuner is big on the 19T. The compressor maps for the 19T are not that dissimilar from the 16G - plenty of top end. I have read some accounts of the 16G not spooling until near 4000. That would make me cry.

I spoke with GS about the deletes. They said the effect on spool would be minimal despite what their web site says:

GrimmSpeed

"On a typical STG 2 setup you are going to realize an increase of 5-10tq/5-8hp in the low end, 10-15tq/8-12hp in the mid range, and 5-10tq/5-8hp at the high end. As you can see in the dyno graph, max gains are going to occur in the mid range.

As far as where the gains occur in the power band, your entire power band is going to see an improvement with our TGV Deletes.

These will also give you a quicker turbo spool up. If those gains weren't good enough for you, wait till you add a bigger turbo...the bigger the turbo you put on the bigger the gains are going to be from getting the GrimmSpeed™ TGV Delete
". :confused:

GS makes great stuff, although I think they sometimes exaggerate about their claims.

Wow! Look who's the young 'un now... :tongue:
I'll take young when I can get it. :p
 
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