Manifold and TVG bolt clearance - need help

[Gripless]

looking for in depth Subaru knowledge here… 

 

So I rushed and ordered a SXE compressor cover for the EFR before cert photos, and didn’t account for the 1” bigger inlet. Thought it was only 1/2” bigger. 
 

The turbo with stock efr cover is tucked up close to the manifold and TVG so the silicone pipe was 5mm from the random mounting standoff sticking out of stock manifold.

a)

The current manifold is stock Sti and TVG but all the insides have been ground smooth already.

Also has 5mm thermal gaskets which could be removed.

raduim split rail kit

b)

it’s the right lower in the photo. Big standoff and the TVG bolt.

https://imgur.com/ukuy4aO

 

c) 

needs to hold together at 32psi 

d)

didnt want fancy intake etc and so avoiding that would be nice.

 

 

 

Options I randomly thought up so far..

 

1)

PW 67mm TVG which lower the manifold 12mm from stock. Plus another 5mm of the thermal gasket is removed.

https://processwest.com.au/product/133/PWTD04-Billet-TGV-Delete-Kit-suit-Subaru-01-07-WRX-STI-&-08-17-STI-Raw

Looks like this isn’t enough 

 

2)

Anyone know of the older + spec one fits or flows well? https://forums.nasioc.com/forums/showthread.php?t=2722224

I remember something about GRB 2008+ manifolds having bigger internal runners.

@Andy_Mac mentioned ethrottle mod needed as well. I have a old 2.5L NA 70mm ethrottle body that should match up.

3)

cut the bolt and mount off and leave 5mm to and wire tie that edge. Hope and pray!

 

4)

live with surge in midrange and resell compressor cover.

Easy and cheap option rather than waste more money.

 

5) most aftermarket ones are out as they use the TVG still eg no cosworth, PW or most Chinese knockoffs.

AMS may work but that near $2k just to get me and if not it then resell it. It may also be fatter that stock so potentially worse.

 

 

 

Edited July 28, 2023 by Gripless
Cos I’m dumb af

[Gripless]

The 2.5” original 

 

The 3.5” SXE

inner is same 2.5” with the 0.5” surge all around it.

 

Edited July 28, 2023 by Gripless

[Gripless]

All aftermarket manifolds are out… realised the top mount brackets all bolt up to manifold and nothing but stock will have them.

 

Bolt that is in the way is only a TVG to upper manifold, not the main 4 that go onto the block.

 

New cover also sits closer to compressor wheel as there is not vent to recirculate air so that helps.

[Gripless]

May have just enough space for turbo cover. 

Moving bracket holding up pipe 1-2mm outwards which should gain 2-3mm at top.

 

Cutting off closest mount that is unused. 

Cutting height down on the bolt mount surface on TVG saves 3-4mm
Using screw head not bolt head on same mount saves 3-4mm

Thermal spacers are 8mm so can drop to 3mm ones, or even factory gaskets. Another 5-8mm

All of which hopefully make up the 12.5mm radius increase.

 

can also deform the silicone joiner a bit as turbo and manifold are bolted to block and won’t rub. Even if crushed in the anti surge airways are below the top point on turbo inlet. 

So much effort for tiny gain. 
Well maybe 30-40hp from cover swap. 
 

 

[lowandy]

Look into V8/9 STI Long runner manifold. Doesnt use the TGVs which should help unless you need to keep the TGVs for whatever reason. Are you in Auckland?

[Gripless]

4 minutes ago, lowandy said:

Look into V8/9 STI Long runner manifold. Doesnt use the TGVs which should help unless you need to keep the TGVs for whatever reason. Are you in Auckland?

Yeah, but finding one is not easy and would have to swap throttle body and get new map sensor.

throttlebody should be fine to use the 2.5 NA which is 70mm but same outer size. 
7/8 map sensor isn’t on throttlebody so would need new sensor.

 

[lowandy]

2 hours ago, Gripless said:

Yeah, but finding one is not easy and would have to swap throttle body and get new map sensor.

throttlebody should be fine to use the 2.5 NA which is 70mm but same outer size. 
7/8 map sensor isn’t on throttlebody so would need new sensor.

 

Might be a step even further back but Rev D intake manifolds are long runner. Seems like either way your set up will need to be adjusted but getting rid of the TGVs is a huge step in the right direction for space clearance.