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Discussion Starter · #1 · (Edited)
Let me tell yeah. I had no idea how hard of a decision chosing what turbo to go with for an upgrade. This board has so much good information several different turbos. I was flip flopping back in forth between so many different scenarios! I got fed up with it and So, TODAY I purchased the internally gated SZ49 with the 3" inlet and fatboy wheel upgrade along with porting on the compressor outlet.

I wanted to get some feedback on the supporting mods. Let me know if you think something would work better...

My list of supporting mods
Current:
APS 3" TBE (already have installed with stg 2)
APS 65mm CAI (installed)
Cobb AP

Turbo should be here within a week, so I
Need to order quick:
APS DR 525 FMIC
APS turbo inlet pipe
Nismo injectors 740
APS TGV Deletes
Apexi AVC-R
Fuel Pump
APS BPV
One step colder plugs

Pro Tune

Am I forgetting anything. See something I should substitute for something else; let me know. I want to make sure I do this right the first time. :D
 

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Ok, first thing I'm noticing is the MAF sensor is going to get maxed out with that turbo.

What's peoples opinion of the 740cc injectors? Is there a possibility he could max them out as well?
 

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pt518sti said:
Ok, first thing I'm noticing is the MAF sensor is going to get maxed out with that turbo.

What's peoples opinion of the 740cc injectors? Is there a possibility he could max them out as well?
He won't max out the MAF with pump gas, and probably not even on a lower race gas, say about 103 octane. I have a friend with a legacy running a 20G using a K&N typhoon and he put out 380WHP on a mustang dyno on a mix of 91 plus 114 for an average mix of about 103 in the tank. The 740 injectors have plenty of overhead in them as well. I know Doug from Topspeed had the same injectors on his STi when it was running a SZ55 on C16 putting out 470WHP.

As far as your setup, it looks pretty solid. I'd go with one step colder plugs. Most important is to make sure you get a good tune.
 

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Yea I think you might need to look into some bigger injectors. Perrins, PE, or something else in the 800-850+ cc range might be needed with an SZ49 and the other mods.

This is a question to ask your tuner. Ask them what flow range and injector duty cycle % they recommend, what kind of injectors they recommend, and what they are used to tuning. Then go with their recommendation.
 

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Discussion Starter · #5 ·
Oh, I don't plan on running race gas or meth. Strictly 93 Octane unless I road trip and happen go somewhere that only has 91. I will note the 1 step colder plugs and a protune is a given. Thanks.. Any other on the injectors?
 

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This is similar to what I am doing. 3" inlet FP Green (49lb/min just like the SZ49) but hopefully upgraded with the 8cm exhaust housing.

Get the APS 70mm CAI. The APS turbo inlet pipe is 76mm. Don't choke that off with a wimpy 65mm intake. Upgrade to the 70mm. I am currently running the 70mm APS CAI with Nismo injectors on my stock turbo and she drives beautifully ... especially for a car with bigger injectors and a bigger MAF. These parts were made in heaven to be matched together.

I also recommend NOT getting the APS TGV deletes. Go with a set of ported stock TGVs. They will actually flow more and you won't need the actuator housings from the APS setup if you are getting a ProTUNE.

t
 

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Why wouldn't you want to run meth? Fellow SZ49 owner here.

I have the TGV deletes, don't see why you want to flow more than stock...while you are at it, you should port the manifolds a little bit if you can, it should help spool with a clipped wheel.
 

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I would go with the DR725 instead of the 525. PE850 injectors, and add meth.
Always nice to leave room for growth.

I love my SZ49, although I would probably go SZ55 if I were to do it over.
 

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wow many different opinions here...

stick to the aps525, it's more than enough to cool for the 49 (it's a relevant size to the perrin, which is perfect)....the 725 is overload.

get the bigger aps intake, you'll want to flow more air through the ***** in relation to the larger injectors...as for them 740's are perfect, you don't need anything higher.

the aps tgv's are a waste, you do not need the sensors there. just buy some already ported and welded shut or have a shop do yours it's much cheaper and flows more.
 

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VSGTS14 said:
wow many different opinions here...

stick to the aps525, it's more than enough to cool for the 49 (it's a relevant size to the perrin, which is perfect)....the 725 is overload.

get the bigger aps intake, you'll want to flow more air through the ***** in relation to the larger injectors...as for them 740's are perfect, you don't need anything higher.

the aps tgv's are a waste, you do not need the sensors there. just buy some already ported and welded shut or have a shop do yours it's much cheaper and flows more.
True:tup: The APS525 is a perfect match for a 49 as is the injectors. I have Perrin 816cc and they are more than enough.
 

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hey nice set up personaly i wouldn't go with the 3 inch inlet cuz u will had a hard time fitting the turbo inlet hose unless u do a rotate Down Pipe. 740 incjectors will be fine with the 3 inch turbo inlet ur gonna need aps tgv delete's or something of that brand. idk about that cai thing id go short ram with a heat shield if your woried about heat soak on the intake. add a equal length header to that list. some fuel rails..lines and such walbro pump 255lph or so.and a clutch. stock will work untill the tunes done but if u wanna drive it hard needs to be upgraded. u might need a pill for the wastgate house thingy but ur turbo might come with it oil lines should to gasket's......o yea and dont mix leaded and unleaded fuel like some of these nuckle head's thats askin for detination. lol.. dont forget to zip tie them boost lines they will blow off... might i recommend a perrin ebcs also. stock boost selinod prolly wont last long on that set-up. thats all i can think off well later..
 

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^ok everything you just said was either stated, is wrong, or isn't needed. are there any periods in there??

a. get the 3" it's way worth it if you're going this route anyway...plus you're gonna get the aps inlet and that makes things way easier.

b. do not get ebcs, it's worthless for this setup...get a standalone boost controller such as apexi avc-r or the txs dtec
 

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Discussion Starter · #16 ·
Well, I ordered the 525, Nismo 740, fuel pump, and aps tgv deletes. I forgot to order the APS BPV, but I will get that from the same place that I get teh Apexi AVC-R from.
 

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Was the porting on the deadbolt an additional fee? Or was it included?
 
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