2002 WRX EJ205 Link ECU HP increase?

[K3rm1tTh3Fr0g]

Hello,

I have a 2002 WRX with an EJ205 with VF39 turbo from an 05 STi and all the supporting mods to go along with that.

My tuner, whom I trust, quoted me a 20-40 WHP increase on their dyno from switching nothing but engine management to a Link while on pump gas. I have already the ECU paid for and I am waiting for my tune appointment. Although I'll be upgrading turbos and going flex fuel, so it won't be an apples to apples comparison.

They attributed this gain to the faster processing on the Link coming from the old 16-bit 02 WRX ECU.

They showed me a dyno graph of an EJ205 car with a Link ECU making 300 WHP 300 WTQ on the same VF39 as me on pump gas.

I made 250/225 on the same dyno.

I just want some input on whether or not power gains exist when upgrading from old ECU because I have heard from other tuners that power gains from ECU swaps alone are not possible when everything else is equal.

Thanks!

[Adamw]

It would more depend on how far away from optimum the current tune is rather than ecu processing power.   

[K3rm1tTh3Fr0g]

17 hours ago, Adamw said:

It would more depend on how far away from optimum the current tune is rather than ecu processing power.   

Totally understand.

I thought it seemed silly to essentially call the ECU horsepower in a box but that's pretty much how my tuner described it on multiple occasions.

He directly said: " I do still believe the Link is the way to go. A good comparison is a Pentium 100mhz CPU from the 90s, versus a new Intel i9 CPU from today. Both do the same thing, one just does it light years faster. The ability to make faster calculations alone account for far better driveability than the old 16 bit ECU. The faster processing will also help in spool, again from the faster processing and feedback of the newer computer."

The fact that he showed me a car making 300/300 on the same engine, dyno, turbo, and fuel as me, but just with a Link ECU, makes me believe his claim though....

[dx4picco]

But what is he comparing to? An already tuned ej205 on stock ecu, or a stock tune? 

As Adam said, the more aggressive the old tune was the less you will gain

[K3rm1tTh3Fr0g]

11 hours ago, dx4picco said:

But what is he comparing to? An already tuned ej205 on stock ecu, or a stock tune? 

As Adam said, the more aggressive the old tune was the less you will gain

He is is comparing my current ej205 vf39 pump gas set up tuned on an accessport on a low reading Mainline dyno, to the same setup tuned on pump gas on the Link on the same dyno.

When he asked me out of 10 how aggressive I wanted the tune I said 7.

 

[dx4picco]

then like Adam said, those 40 whp are the step up from7/10 to 10/10 and not really faster processing

[Wildt267]

I wonder if the tuner was referring to the load limit on the 16bit ecus.  My memory was fuzzy but i think you had to do some work around to get the ecu to match fuel at higher load levels. I could see how that would be interpreted that way.

[K3rm1tTh3Fr0g]

1 hour ago, Wildt267 said:

I wonder if the tuner was referring to the load limit on the 16bit ecus.  My memory was fuzzy but i think you had to do some work around to get the ecu to match fuel at higher load levels. I could see how that would be interpreted that way.

Perhaps, however I did discuss running a non OEM ROM with Carberry which allows for speed density and should fix any load limit issues I would imagine...

[02wrx]

A vf39 on a ej205 with injectors, fuel pump, exhaust, and intake will make 300whp using open source or a accessport. With stock ej205 injectors they will be maxed out around 260-270whp. If your in Seattle Washington I would make the drive down to Oregon to have Jarrard tune it either with the accessport or with the link. Seriously is worth it he's been tuning subaru's for 20 years now. His tuning business name is PDX Tuning. He sold his shop to Cobb which was later Bought by Surgeline.  To get ahold of him call Superior Soobie and Import. With running the Link I would add a can lambda and go speed density by using the cobb 4 bar map sensor kit with a gm iat.

[K3rm1tTh3Fr0g]

20 hours ago, 02wrx said:

A vf39 on a ej205 with injectors, fuel pump, exhaust, and intake will make 300whp using open source or a accessport. With stock ej205 injectors they will be maxed out around 260-270whp. If your in Seattle Washington I would make the drive down to Oregon to have Jarrard tune it either with the accessport or with the link. Seriously is worth it he's been tuning subaru's for 20 years now. His tuning business name is PDX Tuning. He sold his shop to Cobb which was later Bought by Surgeline.  To get ahold of him call Superior Soobie and Import. With running the Link I would add a can lambda and go speed density by using the cobb 4 bar map sensor kit with a gm iat.

Thanks. Already have an AEM intake air temperature sensor, and I'm tuned on hybrid speed density and I already have 1050X injectors w/ an Aeromotive FPR and walbro 255 along with rails. I was also planning to add a surge tank with a Walbro 525 in preparation of the GTX3576 Gen 2 I have set aside for when my current motor pops. The surge tank should also take some load off the in-tank pump because we should be close to it's limits on E85 with a 20G I am about to install.

The original question about gaining 20-40WHP was theoretical, I am technically changing turbos, I just am confused by what my tuner said.

And for telemetry have 2 60mm BTI Innovations multi-gauges ready to go on the A-pillar in a JCSpods mount so I'll be able to monitor everything

And their dyno is Mainline which is pretty stingy so I am aiming for 330WHP/300WTQ on a ball-bearing 20g on e85.

After asking my tuner for more info, he said this: "

1. speed speed speed.... think of the most bad ass phone you could get in 2002 for $1500. and then again in 2017. The ecu can do more, faster. it can see speed changes faster because it can look at the engine triggers more frequently. apply this to ignition timing ---- it can time the engine more precisely, especially at higher engine speeds. same for knock detection.

2. drivers... the stock ecu has cost in mind. Does the hardware deliver the emissions requirements and also the advertised power while keeping us in a safe range of operation (so it wont break under warranty)?. good enough.
The new ECU has much better drivers. i mean better like.... higher quality. --- when current starts to pass through a loaded circuit there is a high current low voltage situation as the current starts to flow and it may operate the circuit poorly or with some lag. the better drivers in Motorsport ecus ensure a full current passes through and minimizes fluctuations in the operation of the circuit. ie. more stable. apply this to injectors that operate at alternator voltage, have a mechanical lag time that varies with this voltage, and all the current must pass through a tiny power transistor.
(an analogy could be bigger wire on speakers reduces distortion caused but resistance in the wire and connections).
better drivers mean better spray, which means higher quality (and more consistent) combustion - which is very important for pump gas to boot... but yields the extra power, especially up top in faster engine speeds."

Not too sure what to make of this

 

[02wrx]

You don't really need a surge tank on these when you can buy a radium fuel pump hanger that does the same thing. It's better to have a single pump setup especially on a street car unless you go through the trouble of setting up fail safes to shut the car off or limit rpm before it goes lean under power. The multi pump setups are failure prone from my experience from all the drift cars I've ended up working on with fueling related problems that have to get pulled off the dyno. You would need to watch amperage draw from each pump and figure out how to monitor that on a Link. Running 2 pumps in a surge tank with one going out you won't know it's going lean until it's under boost where more fuel volume is required. You can run a walbro 450 and make past 600whp on e85. My 02 wrx with 300,000 on the shell has a 2.5 hybrid build using JE pistons to make it a true 2.5 even with the 2.0 heads, Blouch 18g ball bearing turbo, id1050's stock lines and rails, dw 300 fuel pump, intake, exhaust, cobb 4 bar map sensor so it can run speed density, V7 Link G4x with gauge art can gauge display, ect. It is making 324whp at 14.5psi on our shops DynoJet dyno with very conservative timing. On 18-20 psi and more timing it should be past 350whp on 91 pump gas. With e85 it should hit around 400whp. On the stock clapped out factory ecu with a accessport running maf based my maf was maxed out at 4.95 volts while running 20psi and only making 317whp. The Link fixed hesitation issues I had been dealing with on the factory ecu and other weird idle control problems. Another lower mileage car at the shop I work at with a very similar build to mine made 377whp on 91 pump gas on the stock ecu running maf based and 21-22psi of boost. I would agree with some of what your tuner said but it's not going to create huge power just by adding a Link to it if the factory is working perfectly. I could see it making 20-40hp more like mine if the factory ecu has problems. 

[K3rm1tTh3Fr0g]

15 minutes ago, 02wrx said:

You don't really need a surge tank on these when you can buy a radium fuel pump hanger that does the same thing. It's better to have a single pump setup especially on a street car unless you go through the trouble of setting up fail safes to shut the car off or limit rpm before it goes lean under power. The multi pump setups are failure prone from my experience from all the drift cars I've ended up working on with fueling related problems that have to get pulled off the dyno. You would need to watch amperage draw from each pump and figure out how to monitor that on a Link. Running 2 pumps in a surge tank with one going out you won't know it's going lean until it's under boost where more fuel volume is required. You can run a walbro 450 and make past 600whp on e85. My 02 wrx with 300,000 on the shell has a 2.5 hybrid build using JE pistons to make it a true 2.5 even with the 2.0 heads, Blouch 18g ball bearing turbo, id1050's stock lines and rails, dw 300 fuel pump, intake, exhaust, cobb 4 bar map sensor so it can run speed density, V7 Link G4x with gauge art can gauge display, ect. It is making 324whp at 14.5psi on our shops DynoJet dyno with very conservative timing. On 18-20 psi and more timing it should be past 350whp on 91 pump gas. With e85 it should hit around 400whp. On the stock clapped out factory ecu with a accessport running maf based my maf was maxed out at 4.95 volts while running 20psi and only making 317whp. The Link fixed hesitation issues I had been dealing with on the factory ecu and other weird idle control problems. Another lower mileage car at the shop I work at with a very similar build to mine made 377whp on 91 pump gas on the stock ecu running maf based and 21-22psi of boost. I would agree with some of what your tuner said but it's not going to create huge power just by adding a Link to it if the factory is working perfectly. I could see it making 20-40hp more like mine if the factory ecu has problems. 

My tuner/shop prefers to use the Radium single pump surge tank to tackle fuel issues because it addresses the fuel starvation issue present on these cars when cornering, and takes the load off of one pump to solve the high RPM current/voltage drop issues. The radium hanger says specifically in the documentation that it's not a surge tank and doesn't operate as one functionally. And yes, the in tank pump setup can have a baffle you can install to keep fuel around the pump/hanger but my guess is my tuner would consider that a band-aid solution and inferior to a proper surge tank setup that has its own fully pump assembly constantly being fed by a lift pump in the tank. Also the cost of the the surge tank vs the in tank pump is a wash so I'd rather do it the way my tuner suggests.

I plan to opt for a Walbro 525 over a 450 because I saw a GTX3576 G2, the same turbo I have set aside in my garage forna built 2.5L down the line, run out of fuel on the Boost Creep's dyno.

And when the car gets big brakes it will see some track and auto X duty.

[Stevieturbo]

largely your tuner is full of it.

 

The OEM ecu is extremely good, perfectly fast enough, and from the factory, extremely well tuned. His comparisons or analogies are not valid in the real world.

 

In this instance the biggest factor as to your engine making power or not ( and doing it safely and reliably ), is the person tuning it.

 

the second factor is the dyno and whatever numbers you actually believe. All dynos read different, all dynos can be made to read different, and dyno operators can use their dyno in different ways. Same with tuners and ecu's, there are good and bad, all too often bad is operator related. If he tuned your car on the dyno, and all external factors remained the same and you seen good gains from before and after, that's the primary function of using a dyno. Comparing to other dynos, other setups etc etc...can be a minefield.

[K3rm1tTh3Fr0g]

7 hours ago, Stevieturbo said:

largely your tuner is full of it.

 

The OEM ecu is extremely good, perfectly fast enough, and from the factory, extremely well tuned. His comparisons or analogies are not valid in the real world.

 

In this instance the biggest factor as to your engine making power or not ( and doing it safely and reliably ), is the person tuning it.

 

the second factor is the dyno and whatever numbers you actually believe. All dynos read different, all dynos can be made to read different, and dyno operators can use their dyno in different ways. Same with tuners and ecu's, there are good and bad, all too often bad is operator related. If he tuned your car on the dyno, and all external factors remained the same and you seen good gains from before and after, that's the primary function of using a dyno. Comparing to other dynos, other setups etc etc...can be a minefield.

I think he's making those claims because it's a 16-bit ecu. Anyway he continued:

"the LINK will make more power with the same timing, same lambda and same boost. that is proven on my dyno.

Yes OEMs have the advantage of millions of bucks to engineer an ecm to work for them. With that extra oem engineering money working with an outside company to design and supply the ecms... and the thousands of hours of calibration they perform you can nail down that trigger pattern and voltage arming windows hell yea. It has to work like that since they have to un-shelve the thing and put it in blind and it has to work. There is no way any individual tuner or even a larger company like cobb or link can come close to the resources a company like BOSCH or DENSO has when it comes to oem ecm engineering and calibration. But since denso needs to make tens of thousands of these units, (and in subaru's case, the ecm that pickup hardware was designed over 20 years ago has worked on their ej platform in every chassis since) --- cost is a leading factor. period. Link does not, they get to make a balanced product that accomplishes their goals and meets the price they want.

Yes, hardware is faster than software.... always has been. And there is SO much more to the link (or haltec or aem) than just, 'its faster'."

He also told me about a car with a 16g on a ej205 that directly picked up 20whp and 35ft lbs on the same boost when upgrading to a Link on pump gas on the same boost.

[02wrx]

On 8/5/2021 at 8:01 PM, K3rm1tTh3Fr0g said:

My tuner/shop prefers to use the Radium single pump surge tank to tackle fuel issues because it addresses the fuel starvation issue present on these cars when cornering, and takes the load off of one pump to solve the high RPM current/voltage drop issues. The radium hanger says specifically in the documentation that it's not a surge tank and doesn't operate as one functionally. And yes, the in tank pump setup can have a baffle you can install to keep fuel around the pump/hanger but my guess is my tuner would consider that a band-aid solution and inferior to a proper surge tank setup that has its own fully pump assembly constantly being fed by a lift pump in the tank. Also the cost of the the surge tank vs the in tank pump is a wash so I'd rather do it the way my tuner suggests.

I plan to opt for a Walbro 525 over a 450 because I saw a GTX3576 G2, the same turbo I have set aside in my garage forna built 2.5L down the line, run out of fuel on the Boost Creep's dyno.

And when the car gets big brakes it will see some track and auto X duty.

For some reason I thought the hanger for the 02-07 radium hanger was built similar to the 8-14 where it incorporated a check ball. I could see the need for a surge tank for high-g extended cornering. The factory tank is already baffled around the pump so you technically could put fuel cell foam around it to prevent sloshing but for dedicated track car I would opt for a surge tank in the spare tire well. Fuel volume is the biggest factor when running out of fuel you can run a 450lph pump but it can only flow so much through a 5/16" or 3/8" line.

6 hours ago, K3rm1tTh3Fr0g said:

I think he's making those claims because it's a 16-bit ecu. Anyway he continued:

"the LINK will make more power with the same timing, same lambda and same boost. that is proven on my dyno.

Yes OEMs have the advantage of millions of bucks to engineer an ecm to work for them. With that extra oem engineering money working with an outside company to design and supply the ecms... and the thousands of hours of calibration they perform you can nail down that trigger pattern and voltage arming windows hell yea. It has to work like that since they have to un-shelve the thing and put it in blind and it has to work. There is no way any individual tuner or even a larger company like cobb or link can come close to the resources a company like BOSCH or DENSO has when it comes to oem ecm engineering and calibration. But since denso needs to make tens of thousands of these units, (and in subaru's case, the ecm that pickup hardware was designed over 20 years ago has worked on their ej platform in every chassis since) --- cost is a leading factor. period. Link does not, they get to make a balanced product that accomplishes their goals and meets the price they want.

Yes, hardware is faster than software.... always has been. And there is SO much more to the link (or haltec or aem) than just, 'its faster'."

He also told me about a car with a 16g on a ej205 that directly picked up 20whp and 35ft lbs on the same boost when upgrading to a Link on pump gas on the same boost.

I've seen factory ecu's especially when 20 years old, parts failing, and pissed off will pull ignition timing even with no knock event. Even with knock control turned off or heavily desensitized sometimes they will still pull timing. Of coarse the Link is going to pick up power when compared to circumstances like that which is what I think your tuner is talking about. I've worked on ej205 cars making 500whp with factory ecu's it really depends on the setup and what the person wants. The Link is better all round from how versatile it is and the support behind it. Which is why I would recommend people buy it over a new factory ecu.

[dx4picco]

Exactly

Many reasons to get a link but not for the one your tuner pushes you

[K3rm1tTh3Fr0g]

22 minutes ago, 02wrx said:

For some reason I thought the hanger for the 02-07 radium hanger was built similar to the 8-14 where it incorporated a check ball. I could see the need for a surge tank for high-g extended cornering. The factory tank is already baffled around the pump so you technically could put fuel cell foam around it to prevent sloshing but for dedicated track car I would opt for a surge tank in the spare tire well. Fuel volume is the biggest factor when running out of fuel you can run a 450lph pump but it can only flow so much through a 5/16" or 3/8" line.

I've seen factory ecu's especially when 20 years old, parts failing, and pissed off will pull ignition timing even with no knock event. Even with knock control turned off or heavily desensitized sometimes they will still pull timing. Of coarse the Link is going to pick up power when compared to circumstances like that which is what I think your tuner is talking about. I've worked on ej205 cars making 500whp with factory ecu's it really depends on the setup and what the person wants. The Link is better all round from how versatile it is and the support behind it. Which is why I would recommend people buy it over a new factory ecu.

He may be literally just referencing tunes he's done before that have gained horsepower directly. Like the ej205 16g tune he mentioned to me that picked up 20whp and 35whp.

Even if his analogies don't exactly translate, the results he's shown me have spoken for themselves.