BRZ STI NA with more power

[ZDan]

Originally Posted by aesthetect

^ maybe im misunderstanding you but tuning the car to slight rich from stoiciometric tends to produce more torque. slightly lean giving a bit better fuel economy. either way youre definitely right in the fact that theres not likely to be a lot of gain to be had by modding this factory FA 2.0 NA.

When I said "optimal", I wasn't referring to stoich, but rather optimal for maximum power. It is conservative to tune on the rich side of *that*. So if 13:1 is optimal for power, it's conservative to tune to, say, 12.5-12.8:1, and doesn't cost you much in terms of power. If the factory tune at WOT doesn't get richer than ~12.5:1, there's not going to be much to gain from a tune alone.

[Dimman]

Originally Posted by Harinjo

i just got a new information today about the BRZ STI -
no turbo! - it will be the same FA engine but with more power -
hopefully with some more engine displacement.

i will get more news about engine,suspension,brakes and more monday or tuesday...

Weren't you the guy that for months was telling everyone that your 'secret sources' told you that there was going to be a turbo BRZ?

(Still no :facepalm: smiley?)

Edit:

Originally Posted by ZDan

In the world most of us live in, 75 lb-ft/liter n/a is still about it.

Despite the existence of cars that claim 85 and 88 lb-ft/liter (458 Italia), a tune isn't going to take the FR-S from 150 lb-ft to 170-176 lb-ft, I can *promise* you this.

What you *can* expect is for similar n/a torque/hp gains per mod $$$ as an S2000. I.e., meaningful additional n/a gains are going to be relatively costly...

Depends on your definition of 'tune'. Given the tech in this car, if they focused on higher, narrower output instead of the wide, fat torque curve of the stock car, 170 lb-ft should be no problem. But the tuning may require changes to the header and intake manifold lengths/diameters.

[ZDan]

Originally Posted by Dimman

Depends on your definition of 'tune'. Given the tech in this car, if they focused on higher, narrower output instead of the wide, fat torque curve of the stock car, 170 lb-ft should be no problem. But the tuning may require changes to the header and intake manifold lengths/diameters.

I wouldn't consider a full exhaust and custom/aftermarket intake including runners to be included in a "tune", but even with that, going from 150 to 170 lb-ft on the stock 2.0 liter engine would still be a significant challenge.

[Levi]

If the BRZ get "only" 50 PS more and loses 50 kg, the difference on a 1200 kg will be huge. In fact on such a light car any difference in power, torque and weight will be felt. Those that won't feel this, are used to overpowered which they don't even drive to 60% of there potential.

[concept_cynic]

Originally Posted by ZDan

I wouldn't consider a full exhaust and custom/aftermarket intake including runners to be included in a "tune", but even with that, going from 150 to 170 lb-ft on the stock 2.0 liter engine would still be a significant challenge.

I agree. I think the stock engine is tuned to its peak right now. Maybe someone can pick up a few hp but not much. However, I think the aftermarket will have cams, headers, exhaust, intake, etc... that will bump up the tq in the 170 range and up the rpm too. It seems like a 7500rpm reline is low for a 86x86 engine?

My personal thought (without any info to back this up) is this engine has some really small cams in them right now.

[nrclptcnsmniak]

This just dawned on me ... If this is a tuners car then why would they leave no extra room for power in the engine? Just a thought.

[exmayol]

Originally Posted by Levi

If the BRZ get "only" 50 PS more and loses 50 kg, the difference on a 1200 kg will be huge. In fact on such a light car any difference in power, torque and weight will be felt. Those that won't feel this, are used to overpowered which they don't even drive to 60% of there potential.

Amen! Nothing compares with ability to feel that power increase on a daily basis rather than just have a dyno sheet to look at.

[BeRZercar]

Originally Posted by nrclptcnsmniak

This just dawned on me ... If this is a tuners car then why would they leave no extra room for power in the engine? Just a thought.

So your premise is that because this was branded a tuners car, the oem drivetrain engineers will leave hp/tq on the table to be opened up by tuners on purpose? Vs tuning the engine to give the best power while not sacrificing day to day drivability and reliability? I'm betting that the OEM engineers are as enthusiastic about this car/engine as we are.

[Dimman]

Originally Posted by concept_cynic

I agree. I think the stock engine is tuned to its peak right now. Maybe someone can pick up a few hp but not much. However, I think the aftermarket will have cams, headers, exhaust, intake, etc... that will bump up the tq in the 170 range and up the rpm too. It seems like a 7500rpm reline is low for a 86x86 engine?

My personal thought (without any info to back this up) is this engine has some really small cams in them right now.

Funny how in the olden days tuning was exactly that, header, intake and exhaust sizing. Carbs too...

86mm stroke and 7500 rpm puts the mean piston speed ~4200 ft/min which is highish for 'stock' Toyota or Subaru rods, I think. 2JZ also had 86mm stroke and was limited to under 7k I believe.

But if they over-built the rods intending for more revs, who knows?

[Mitch]

Originally Posted by nrclptcnsmniak

This just dawned on me ... If this is a tuners car then why would they leave no extra room for power in the engine? Just a thought.

It's not a tuner's car, it's an enthusiast's car. The first thing an enthusiast would criticize is the manufacturer not making it as good as they could have made it given their constraints.

[tranzformer]

Originally Posted by Mitch

It's not a tuner's car, it's an enthusiast's car. The first thing an enthusiast would criticize is the manufacturer not making it as good as they could have made it given their constraints.

I would have to agree. While I might have enjoyed moding my car when I was younger, I'm at the point where I would prefer to have the car close to perfect from the factory (realizing certain aspects might need to be cut for a production car and to meet varied preferences of customers). If this car is as fun as it sounds like it will be, I have no problems leaving it stock. Fun to drive = fun to drive. That is what I care about most.

[Dark]

30hp more a few tenths of pounds less, it will appeal to me.

[tranzformer]

Originally Posted by Dark

30hp more a few tenths of pounds less, it will appeal to me.

Like 3/10th or 1/10th of a pound less? I want 30-40kg less weight.

[Dark]

Originally Posted by tranzformer

Like 3/10th or 1/10th of a pound less? I want 30-40kg less weight.

My mistake. I mean about 50-60 lb