nikitopo's BRZ OEM+ build

[nikitopo]

Originally Posted by Mr.Impreza

Stage 1 Tune is great! Happy to know you got it and enjoying the car even more now
I love it also!

My only objection is that the torque has a peak in the mid revs (after the dip) and on higher revs the engine looks to not have much power. The acceleration is not so good. It is different than the stock tune where the engine had more torque higher. I think that it ruins a bit the original character of the car. Maybe my other mods and the light weight make the effect more intense. It is quite noticeable.

This week I'll flash back the stock tune, because I have a scheduled service. It is a good opportunity to decide if I'll keep it afterwards or flash back the OFT tune.

[nikitopo]

I did some checks with the factory tune. It is definitely much better on higher rpm's. I am tempted to stay now with this tune. No idea why the OFT tune is not that strong in the high rev range.

[Mr.Impreza]

Originally Posted by nikitopo

I changed my rims and took some pictures of the suspension. The pictures are in the first post. Next step will be to update the header with the 17MY one.

Changes are that the exhaust pipe branches have been shortened to equal lengths (16MY and previous years had almost equal lengths) and exhaust pipe layout has been strengthened out to reduce pressure loss. Additionally, the pipe diameter has been increased between 5-8%:



Not too many options here for an aftermarket header. I want to be "legal" safe.


One question:

Is it safe to run OFT Stage 1 tune with the changed OEM header? I understand that it might not be optimal for performance, but do you think the AFRs will be OK?

Now you even got me interested in this option.
I wanted the Fujitsubo Header....I still do...if i find it used without a cat burnt out since they seem to have cat failures a lot.
I can't risk buying a header for $2500 with no warranty and having the cat fail.
Also, for legal reasons...i feel better knowing I have a stock header instead of an aftermarket header since I'm already running a catless front pipe.
So, if this 2017 header has some gains over the 2013-2016 one I'd probably choose this as an option and get a custom tune for it.

Originally Posted by nikitopo

I did some checks with the factory tune. It is definitely much better on higher rpm's. I am tempted to stay now with this tune. No idea why the OFT tune is not that strong in the high rev range.

Hmmm, not sure why you are feeling this. For me personally, the Stage 1 tune is night and day difference compared to the stock tune. When I went back to the stock tune to have a dealer visit, the car drove so bad haha.

Have you maybe considered getting a custom tune from OFT?
I'm actually debating on getting a custom tune from them....wondering if there would be any benefits for us.

[nikitopo]

Originally Posted by Mr.Impreza

Now you even got me interested in this option.
I wanted the Fujitsubo Header....I still do...if i find it used without a cat burnt out since they seem to have cat failures a lot.
I can't risk buying a header for $2500 with no warranty and having the cat fail.
Also, for legal reasons...i feel better knowing I have a stock header instead of an aftermarket header since I'm already running a catless front pipe.
So, if this 2017 header has some gains over the 2013-2016 one I'd probably choose this as an option and get a custom tune for it.

I wanted to install the Toda Racing header, but it is catless and not legal here. However, I noticed that the branch diameters are almost the same:

Toda: 45mm, 50mm
Stock '17 MT: 45 mm, 48.6mm



Additionally, the shape is similar.

So, I assumed that the new stock header is better for a stock engine. I'll let you know when it is installed. Currently it is on the way ..

[Mr.Impreza]

Originally Posted by nikitopo

I wanted to install the Toda Racing header, but it is catless and not legal here. However, I noticed that the branch diameters are almost the same:

Toda: 45mm, 50mm
Stock '17 MT: 45 mm, 48.6mm



Additionally, the shape is similar.

So, I assumed that the new stock header is better for a stock engine. I'll let you know when it is installed. Currently it is on the way ..

Good to know, I'm looking forward to the feedback!

[Tcoat]

Originally Posted by nikitopo

I wanted to install the Toda Racing header, but it is catless and not legal here. However, I noticed that the branch diameters are almost the same:

Toda: 45mm, 50mm
Stock '17 MT: 45 mm, 48.6mm



Additionally, the shape is similar.

So, I assumed that the new stock header is better for a stock engine. I'll let you know when it is installed. Currently it is on the way ..

You will still need to tune for the header. Just changing to the larger pipes will do nothing without tuning to take advantage of it.

[mrg666]

Originally Posted by nikitopo

Why are you saying that? Fujitsubo's and Ft-86 Speedfactory's catted headers were giving gains even with the stock tune. The idea is that the exhaust gases will flow a bit better and there will be less resistance in the combustion chamber. I agree that the gains will be better with a custom tune, but I cannot imagine that there will be no gains stock.

Anyway, I'll do a dyno run after the change. Just to be sure that the engine output is good and that there aren't issues with any of the installed parts. If the torque is consistent across the whole range and if the max. output is between 175-180whp, then I'll be satisfied.

Cat is stock header's main restriction. Since they don't mention any cat improvement, I think the gain will be limited if any with larger piping. I am curious to see your dyno, hope you prove me wrong.

I really want to get an Ace header. But, like you, legal status of driving catless header is making me worry. Taking it off would be such an expensive disappointment.

[Tcoat]

Originally Posted by nikitopo

I cannot imagine how you can do a custom tune without dyno the car at the same time. Monitoring remotely different parameters (AFR, IAM, FLKC, etc.) will give you an indication that the tune is not causing issues, but not so much if the output is actually better. Fact is that every engine is different and a canned tune might not work always good. Something that worked well on a specific development car, a specific day and with a specific fuel, might not work as well in another car. Stage 1 canned tune on my car was much better on the mid-rev range, but it was definitely weaker on high-rev range. It didn't pull that much after 5k rpm. Maybe the combination with the other parts didn't work so well, although Shiv was sure that the bigger tb will not cause issues. This behavior disappeared when I flashed back the stock tune.

Overall, if there was a good tuner over here then I would make a custom tune. However, they don't know this engine very well. I wouldn't like to make a program with someone who has tuned maybe a couple of FA20 engines. This is a proper sports car and not like tuning a camry. Besides, the stock tune is not that bad. The story that it run a very rich AFR and that it was made in a rush doesn't hold any more. Even the '17+ cars don't run very long with the leaner AFR and after a short time at WOT they start injecting more fuel and change to a richer AFR.



Why are you saying that? Fujitsubo's and Ft-86 Speedfactory's catted headers were giving gains even with the stock tune. The idea is that the exhaust gases will flow a bit better and there will be less resistance in the combustion chamber. I agree that the gains will be better with a custom tune, but I cannot imagine that there will be no gains stock.

Anyway, I'll do a dyno run after the change. Just to be sure that the engine output is good and that there aren't issues with any of the installed parts. If the torque is consistent across the whole range and if the max. output is between 175-180whp, then I'll be satisfied.

Yes there will be slightly better flow. The car does not know this though. It will still only provide the fuel and air mix it is told to from the stock tune. You could open up the whole exhaust but if you don't change the tune to make use of it there will be little or no effect. This is why tuning exists.

[Tcoat]

Originally Posted by nikitopo

Are you suggesting that the AFR will be too rich or just that it'll be possible of more gains with a tune? What I mean... is it safe to run stock?

Perfectly safe to run without a tune. Just no gains.
The total cumulative changes to intake, manifold, exhaust, engine, drive and tune of the 17s netted a whopping 5 hp. Just swapping the the exhaust manifold (it isn't a header really) isn't going to gain a thing. There is no magic bullet to get gains by bolting a single part of a 17 onto an older one.

[Tcoat]

Originally Posted by nikitopo

Some are saying that the '17 gains are 5hp, others saying they are 15-20hp and that the pre-17 models were lower than the factory 200ps specification. Anyway, we'll see...

Funny how they say the new is higher but the old is lower. The official numbers are the numbers we need to work with not what sombody got on a different dyno. Dynos are useless for comparing car against car since they are not all the same. The numbers can be twisted anyway you like but that does not change the fact that parts bolted on without tuning for them do almost nothing.

[Tcoat]

Originally Posted by nikitopo

Who specified the official numbers? The engineering team or the marketing department? Don't you think it was too much of a coincidence to specify the initial engine output to a 200ps? Why not 193ps or 197ps?

About the tuning, I agree that if the engine needs re-calibrication then it is needed. The same if the AFRs are out of the factory specs. Otherwise, I am sorry but I am too sensitive with this kind of "business".

I don't think there is a better person to clarify the magic of ECU tuning than this one:

Doesn't matter who came up with the numbers they are what they are and any number of conspiracy theories can be thrown at them but they are official. Maybe the original was 202 and they rolled it back? I hate the numbers game when things get twisted one way or the other to try and prove a case.

The tuning was my whole point all along and the real reason I posted here anyway. Adding some parts at random and hoping for the same or better results without doing the whole thing is wasting time and money. Adding just the header from a whole new system that gave an OFFICIAL 5 HP gain is like taking one piece of a one hundred piece puzzle, placing on a table and expecting to see the picture from the box. It just isn't going to happen.

I am truly at a loss on how you think adding one slightly changed part is going to get you any gains without tuning to take advantage of those minor changes.

[Tcoat]

Originally Posted by nikitopo

Our disagreement is related with the 5hp gain. You base your argument that this number is official and thats it, although you want to IGNORE that hundrends of dynos were reading the pre-17 model MT cars lower than expected and the situation changed after the revision. Even yourself you confirmed once that the gains are +15hp. I don't know why you changed now your mind. I won't continue to argue with you and it doesn't make sense to dig up your old comment. Thanks for posting to my thread.

You do understand the two totally different types of HP being talked about right? The official rated HP is net and measured at the crank without the rest of the drivetrain. The lower number dyno numbers are Wheel HP and include the loss from the drive train. You are not going to get 200 or 205 at the wheels on a stock car. They are not "lower than expected" they are exactly what would be expected from any car when measuring WHP instead of the rated net HP. So, since you can expect about the same loss on a dyno if the 200 net HP cars read at between 170 and 175 then the 205 should dyno in between about 175 and 180. You are still not getting a huge bump from the cumulative 2017 additions and virtually zero from any single one of them. The situation has not changed and no matter how you look at it the gains on the 17 are minimal.

You started the thread it but is not "yours". It is public. I was just trying to help by pointing out something you seemed confused on but you just don't want to hear it. You are throwing away your money on a 17 manifold if you are expecting any gains from just bolting it on and not tuning for it. Even with a tune you will only get a fraction more than you would have got from a tune with the original manifold.

[nikitopo]

Either you like it or not most of the pre-revision cars were reading lower than the 170whp number you mentioned. Dyno type and specific calibration can make a difference, but these low readings were quite common especially on early '12 production cars. This is not the same with the revised cars. All these have been discussed in detail more than a year ago and were admitted by people that worked actually in the project.

"Upgraded engine, catalog about 5 horsepower more. Realistic more like 15 to 20 because it's actually... the real horsepower is actually closer to the catalog horsepower now"

[nikitopo]

I received yesterday the new factory exhaust manifold. Amazing build quality, thermal coating and very well thought design. I haven't seen something similar from the high quality aftermarket brands:




I'll install also the metal thermal shield:




Even the wrap paper has an anti-corrosion additive: