Cobb Tuning would like to offer a larger than stock turbo for the LGT...

I have been given permission and authorization to specify and develop a AccessPORT map for use with a larger-than-stock turbo on the LGT. I have an idea as to what turbo should be used but I would like to get some feedback from you all. Some critical hardware that will be specified with the use of this map are the intake system, fuel injectors, turbo, TMIC, and turbo-back exhaust system. We have already tested different turbos with various fuel injectors and should be able to make a decision as which hardware will be used for this map. But, before the final decision has been made I would appreciate your feedback. I have personally tuned several Garrett, MHI, IHI, FP, Deadbolt, Brand X, Brand Y turbos etc. over the years so we are not limited to a particular brand for the marketing aspect of things...I just want to specify a turbo that perform consistently and provide more flow that the VF40. The vendor needs to be able to supply, service, and support the turbo as well. That means no fly-by-night brand new never seen turbo operations, etc. nor a turbo that has 20 different options as to its configuration (coatings, ported, not ported, clipped, special this, special that, etc.) The turbo must be a stock replacement, not rotated, no super big inlet that requires more hardware, no special oil/anti freeze lines, etc. and compatible with the stock style boost control solenoid. Along the same lines, the stock exhaust manifold and up-pipe (or a better than stock up-pipe that retains heat) will be required, the stock fuel rails will be used (we will test the stock fuel pump), and I will do everything I can to educate the facts about Subarus and tuning. In other words “the #? cylinder is the lean one (not), the fuel pressure drops on the #? injector so fuel rails are needed (not)”, boost is a measurement of restriction (true), bla, bla, bla.

 

First off, please realize that a GT30+ or Red turbo is way too large for this map to be made safe. We are looking to be able to satisfy all of the U.S. market with this map...so running CA91 octane must be taken into consideration (no 20+ pounds of relative boost pressure, damn you 93 octane East coasters ). This map is not going to be a perfectly tuned aggressive map so do not expect that. This map will be a good map to run a larger-than-stock turbo and should be a good map to use for similar set-ups (i.e. to load scaling, injector scaling, base mapping, etc. will be a good starting point). This will still be an improvement over the stock turbo as far as power goes, but we will not be able to satisfy everybody.

 

I will try to keep this to an open discussion, no bashing, just facts and experience. I will read all feedback, respond when needed, and try to get all questions answered. I need to do everything we can to limit tolerance changes. The last thing I want to do is release a base map that needs constant revision (because the wastegates do not perform consistently-like the VF39-or because different exhaust manifolds other than stock are used, the stock headers are ideal). The turbo, fuel injectors, TMIC, and intake all must perform consistently in order to make this work. The availability of the map will not be any time soon…most likely around 90-120 days.

 

Please go ahead and post your ideas for turbos, I await your feedback.

 

 

 

In addition, we need to purchase a used stock LGT turbo so we can use it for development. We want to make this turbo is a stock replacement turbo that requires little if no modifications to the stock turbo system. Please PM me if you have a used LGT turbo for sale.

 

 

 

Take care,

Christian.

I'm a little confused. Are you going to be providing the turbo or designing a map for use with another turbo?

 

The turbos that fit are a very small group. I have the now-discontinued Deadbolt "Stage 2" I would recommend that you set up the map for the Deadbolt TD06-20G.

 

Sounds like a great idea either way.

sounds like the beginning of a great project. I vote for something with a flowrate similar to 18-20g. I know there are several other makes and models that fit that bill. peak boost in the low to mid 3000 rpm range, emphasis on streetability and smoothness, usable torque. look forward to hearing more about this as it develops.

wow....quite a bit surprising but welcome news. good luck selecting that "one ideal bolt-on turbo."

 

Since you want to stick with a Legacy type TMIC (aftermarket like Perrin or AVO) then the only choices that I'm aware of are the Deadbolt LGT-type 18G & 20G or the soon-to-be-released AVO450 & AVO500.

I'm a little confused. Are you going to be providing the turbo or designing a map for use with another turbo?

We will provide an AccessPORT calibration that will work properly with these new turbos. We are doing this to also assist the ProTUNERs and StreetTUNERs so this map will be available in StreetTUNER format so end users will have much of the tuning taken care of in the base map; then they can tune more aggressively from there.

 

We may actually make or specify this turbo ourselves if we are not able to work with some current turbo manufacturers. This is all to be determined.

wow....quite a bit surprising but welcome news. good luck selecting that "one ideal bolt-on turbo."

 

Since you want to stick with a Legacy type TMIC (aftermarket like Perrin or AVO) then the only choices that I'm aware of are the Deadbolt LGT-type 18G & 20G or the soon-to-be-released AVO450 & AVO500.

You are correct about the one ideal turbo, that will not happen. The goal is to test and development calibrations for turbos and intercoolers that are ideally matched and perform consistently. We will be working on T28, 18G, & 20G deravitives for now. We may add more or remove some of the ones we are currently testing. We wanted to hear back from the other LGT owners (I drive one myself) on what they were thinking. Thanks for the information about the various turbos.

 

Take care,

Christian.

I'd say 20G. 18G is too small and not ideally suited for a 2.5L motor.

I'd say 20G. 18G is too small and not ideally suited for a 2.5L motor.

 

FLAME SUIT ON!

FLAME SUIT ON!

 

 

hahaha, this is true.. however, if you plot it on turbos flowchart.. you can see that on the top end, the 18G will be at its very limits.

I will be following this very closely,,,,,somebody sell Christian a stock turbo real quick:)

More than a few have done the STi swap.....VF39. Seems that's the most popular single option, albeit not taking advantage of the LGT hardware

20g.

 

There are not a lot of turbo options for Legacy GT owners. To my knowledge Deadbolt and AVO are the only ones that make. Turbo options are def. something that we need.

More than a few have done the STi swap.....VF39. Seems that's the most popular single option, albeit not taking advantage of the LGT hardware

 

+1 STi swap with the vf39 has been a popular modification. I'm doing an STi swap myself.

*whistles*

In keeping with the simple bolt-on nature of the Cobb upgrade path I'd suggest keeping to the bolt-on turbos, such as the Deadbolt TD06-18g and TD06-20g. The STi manifold swap is a good option, and gives many more turbo options, but realistically most people are more comfortable with stuff that just plugs and plays.... just like the AP.

In keeping with the simple bolt-on nature of the Cobb upgrade path I'd suggest keeping to the bolt-on turbos, such as the Deadbolt TD06-18g and TD06-20g. The STi manifold swap is a good option, and gives many more turbo options, but realistically most people are more comfortable with stuff that just plugs and plays.... just like the AP.

My sentiments exactly, we will not be developing a map for the VF39 on the LGT for this and several other reasons; wastegate inconsistency, cost of new turbo, insufficient flow at high RPM, etc.

Deadbolt TD06-18g. It seems to be the logical turbo upgrade path, without having to do many significant fuel mods, if any.

create a turbo w/ similar cfm rate as a vf39 that bolts up to lgt specific aftermarket tmic

Now! you guys decide to do something....same month I pick up a VF39 swap

hahaha, this is true.. however, if you plot it on turbos flowchart.. you can see that on the top end, the 18G will be at its very limits.

 

That argument could be used with X number of turbos used on various manufacturers(saad, audi, etc).

 

The 18g is still a very solid upgrade over stock dispite tapering off near redline.

Deadbolt TD06-18g. It seems to be the logical turbo upgrade path, without having to do many significant fuel mods, if any.

 

shame there are not any other cheaper options.

too bad forced performance opted not to make a legacy specific 18G.

20G would give good power on low boost levels (stock intercooler and 91 octane). More detonation resistance over the 18G, but sacrificing a little spoolup.

both the db 18g and 20g are good upgrades. each have their pro's and con's.

the 18g will top out near redline, where as the 20g will still have room.

however the 18g will spool up faster then the 20g, which might be good for those that use the car as a daily driver. but those that track the car might not mind the lag of the 20g and want more of the top end.

imho i would say db 20g its got plenty of power and is reasonably priced. the avo is way to expensive, 2k for a turbo is insane.

Christian is a swell guy.