[TheBestAround]

Hey guys! Just looking for some input on some mods I’ve been thinking of running, talked to some reputable tuners around my area they’ve recommended some parts, I’ve also done research, just looking for some input anything you would change or swap out for another? I’m planning on running around 360WHP (In the end) upper end of stock block until it inevitably blows on me. It’s a 2019 STI and I’m currently running an OTS tune with the Cobb DP and catback also from Cobb.

Now the good part, stage 2 parts I want:
FPR: Aeromotive
Intake: Cobb OR ETS (can’t decide)
EBCS: custom from neetronics
Injectors: Bosch 1000 cc
Spark plugs NGK one step cooler
Pickup and baffle: Killer B
Fuel pump: AEM
Radiator: CSF
Crank Pulley: fluidampr
Now for the controversial part, I want an aftermarket BPV, fully recirculating, it may be a waste of money, but personally it’s worth it for more noise without compromising reliability. I was thinking of going with the Grimmspeed BPV, Cobb, or forge diverter valve. I’ve listened to GrimmSpeed BPV on YouTube, I’m a little nervous because it makes a clear flutter sound, so I was assuming it was compressor surge, but GrimmSpeed is very adamant its not and its how they designed it, anyone have any experience? Because the GrimmSpeed one is the one I was leaning towards.

Stage 3 parts I want:
Verticooler (I think I’m running this over front mount, from what I’ve read no heat soak + little to no turbo lag?)
Turbo: Cbob 20g or FP blue
Turbo inlet: Perrin or GrimmSpeed
Up pipe: Tomei
ELH: Tomei
EWG: Tial
4 bar sensor: OMNI
oil filler neck
water/meth injection kit
TGV deletes

Any suggestions on anything would be super great, especially with the BPV.

 

[zax]

Feedback:

I would definitely skip methanol injection. Use E85/flex fuel if its available instead.
Is the Up-pipe necessary to fit that header? If not, use the OEM up-pipe or consider a different header to save cost and installation pain.
The crank pulley - skip it. It's a waste of money.

I didn't think the Verticooler was compatible with the STI-style turbo mounting? Yes, TMIC would be preferable for your setup over a front-mount. ProcessWest has STI-routing versions. Look up IAT relocation and consider this option before tuning.

Radiator - if the OEM radiator isn't cracked, I wouldn't replace it. The stock cooling system is more than adequate. You can save money here.

OK... the BPV... The car has an OEM BPV. With an aftermarket intake, you will hear the OEM bpv just as much as an aftermarket unit (they are both doing the same thing). I would really suggest skipping this unless the OEM unit is leaking (and BTW it can be modified easily to hold over 24PSI of relative manifold pressure).

 

[a5m]

Just to comment on the TMIC, the 17+ STi OEM unit is capable of handling close to 500hp. @killerbmotorsport compared all the aftermarket ones and none except an old Spearco performed better than it. Food for thought.

 

[zax]

You say 17+.

Is the 2017 and later somehow different than the 2008-2016? I wasn't aware of any notable changes.

The pressure drop across the core on the STI unit is much larger than aftermarket bar-and-plate designs.

 

[a5m]

You say 17+.

Is the 2017 and later somehow different than the 2008-2016? I wasn't aware of any notable changes.

The pressure drop across the core on the STI unit is much larger than aftermarket bar-and-plate designs.

I thought they were all the same too 08-21 but apparently the 17+ are the ones to have. Hopefully @killerbmotorspo will chime in and say why as I don't know.

 

[zax]

2017 seems like an odd change-over year.

2019 marked the RA shortblock usage, revised intake routing. It would have made more sense to change during that MY refresh even if the change was minor.

 

[zax]

Interesting. The part number does only correspond to 2015 and 2016 MY STI.

Minor revision only.

21820AA500 for 2017-2021
21820AA470 for 2015-2016

I recall the pinch welds for the pitch-stop were improved for MY2017. Perhaps that's the reason for the part number change -- how the Intercooler mounts up to the engine above the pitch stop. I can't imagine any notable changes internally would have been in store.

 

[zax]

Not sure the accuracy here...

So figured I'd document some findings (and would love input/verification)
04-07 STI Intercooler 21820AA252 - Sanden SIC-TM0030 - STI in Red on top.
08-14 STI Intercooler 21820AA380 - Sanden SIC-TM0170 - No lettering, larger than 04-07.
15-16 STI Intercooler 21820AA470 - Sanden SIC-TM0220 - Top endcap steeper angles instead of roundover.
17-20 StI Intercooler 21820AA500 - Sanden SIC-TM0250 - Mounting for PCV moves from front to top mount of bottom endcap.

Also not sure what changes on the Y pipe on the back, as I've seen 3 different versions through my image searches. Any ideas on that as well?

Original post here: The end all Installing STI TMIC thread.

Different Sanden part number. Could be a modified core. But looks like there was indeed a change to the cylinder head vent routing as minor as it is.

Can confirm, my MY2015 does have the front mounted inserts. Probably a manufacturer core change that necessitated this.