Eliminating torque dip

[PenGun]

The car has little left to gain from anything near stock. Its already pretty well maxxed for what it is. You can pull a bit here and there but outside of boost there's not much there.


I have never felt the torque dip. If I'm in a hurry its usually down two, and 5 grand gets the job done.

[BrahmaBull1990]

Originally Posted by PenGun

The car has little left to gain from anything near stock. Its already pretty well maxxed for what it is. You can pull a bit here and there but outside of boost there's not much there.


I have never felt the torque dip. If I'm in a hurry its usually down two, and 5 grand gets the job done.

Is your car fully stock? Have you tried a header+ stage 2 tune?

Just curious as I do not agree at all and this is the internet, so I can object. Bolt-ons will never equal FI, but FI is not everyone's goal and there is a lot between fully stock and FI, imo.

[PenGun]

Originally Posted by BrahmaBull1990

Is your car fully stock? Have you tried a header+ stage 2 tune?

Just curious as I do not agree at all and this is the internet, so I can object. Bolt-ons will never equal FI, but FI is not everyone's goal and there is a lot between fully stock and FI, imo.

What's FI? I'm very old. The motor at 12.5/1 and happily doing 7 grand and does not have much left. You could do a few things but most of what needs to be done, is done. Its a 2 litre motor and adding slightly better flow and exploiting your computer, variable valves, etc will not give you much back. Adding boost will, but you should rebuild the motor to do that well.


Now its a 'sports car' and is built to be one so well, that there's not much left, again. If you want a muscle car you are in the wrong one. I built a 69 Cutlass with a 502 from the General and it would do stupid power stuff all day, but even with about 8 grand in the suspension, and Gatorbacks, its was scary in the twisties. The BRZ is just fun, till it slides, then its more fun. The Cutlass nearly killed me a couple of times.

[BrahmaBull1990]

Originally Posted by PenGun

What's FI? I'm very old. The motor at 12.5/1 and happily doing 7 grand and does not have much left. You could do a few things but most of what needs to be done, is done. Its a 2 litre motor and adding slightly better flow and exploiting your computer, variable valves, etc will not give you much back. Adding boost will, but you should rebuild the motor to do that well.


Now its a 'sports car' and is built to be one so well, that there's not much left, again. If you want a muscle car you are in the wrong one. I built a 69 Cutlass with a 502 from the General and it would do stupid power stuff all day, but even with about 8 grand in the suspension, and Gatorbacks, its was scary in the twisties. The BRZ is just fun, till it slides, then its more fun. The Cutlass nearly killed me a couple of times.

Good points. “FI” is forced induction; so supercharger or turbocharger. These are for certain not muscle cars, but you can get a good amount, percentage-wise, over stock with exhaust work and tunes (e85, too, if you’d like). Again, this is just my opinion after doing header and a tune - someone with FI is laughing at me

[PulsarBeeerz]

Originally Posted by PenGun

What's FI? I'm very old. The motor at 12.5/1 and happily doing 7 grand and does not have much left. You could do a few things but most of what needs to be done, is done. Its a 2 litre motor and adding slightly better flow and exploiting your computer, variable valves, etc will not give you much back. Adding boost will, but you should rebuild the motor to do that well.


Now its a 'sports car' and is built to be one so well, that there's not much left, again. If you want a muscle car you are in the wrong one. I built a 69 Cutlass with a 502 from the General and it would do stupid power stuff all day, but even with about 8 grand in the suspension, and Gatorbacks, its was scary in the twisties. The BRZ is just fun, till it slides, then its more fun. The Cutlass nearly killed me a couple of times.

There are many NA dyno results that refute those statements. haha E85 in particular loves that 12.5:1 compression. Also people have been running conservative boost setups on this engine for the better part of 7-8 years.

I take it you are new to the platform??

[NoHaveMSG]

Originally Posted by PulsarBeeerz

There are many NA dyno results that refute those statements. haha E85 in particular loves that 12.5:1 compression. Also people have been running conservative boost setups on this engine for the better part of 7-8 years.

I take it you are new to the platform??

I think you are misinterpreting him a bit. I think his point is just that modern engines are far more optimized out of the box then what was considered a sports car 30+ years ago.


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[CB750F]

After the warranty was over I put a UEL & tune. I rarely felt the dip in those 5 yrs & I drive speed limit/normal. UEL/tune adds a little more fun but I did it more for sound. Not very cost effective if your doing for power.

[Dzmitry]

Originally Posted by PulsarBeeerz

There are many NA dyno results that refute those statements. haha E85 in particular loves that 12.5:1 compression. Also people have been running conservative boost setups on this engine for the better part of 7-8 years.

I take it you are new to the platform??

As NoHaveMSG said, you're just misunderstanding his point. The engine is near its peak, there isn't much to gain. E85 is like a cheat - not only is it not available to everyone, but you are putting in fuel that was never designed for the platform. If you consider the classic way of tuning, aside from going FI of course (which completely changes the characteristics of this car), you have very little to gain, even from removing both cats. It'll flatten your torque curve and give you some ponies up top, and that's it. That's in simple terms, obviously there is a nice little gain throughout the powerband, but not anything crazy. This was just a well designed engine from the start, hence the 205 HP output from a 2.0L N/A.

[FR-S2GT86]

Originally Posted by Dzmitry

As NoHaveMSG said, you're just misunderstanding his point. The engine is near its peak, there isn't much to gain. E85 is like a cheat - not only is it not available to everyone, but you are putting in fuel that was never designed for the platform. If you consider the classic way of tuning, aside from going FI of course (which completely changes the characteristics of this car), you have very little to gain, even from removing both cats. It'll flatten your torque curve and give you some ponies up top, and that's it. That's in simple terms, obviously there is a nice little gain throughout the powerband, but not anything crazy. This was just a well designed engine from the start, hence the 205 HP output from a 2.0L N/A.

Yes, think about this:
My '68 Torino with a 302 (that's approximately 5.0 liters) made a whopping 205 HP stock. The 3.0 engine in my '00 Solara makes about 198 HP stock. This little 2.0 liter in these cars makes 2.5 times the HP per cubic centimeter than the engine in my Torino did.

However, which of these three engines do you think will last the longest? There's a trade off when it comes to high output and reliability. For those who are wondering, the Torino is still in the road with it's original engine. The Solara as well.

My point is, without some form of radical design change, the N/A internal combustion engines being produced today are just about at their power limits if you want that engine to last any length of time.

Which brings me to that redesigned rotary engine with the seals in the stator section. Although the seals will still have to be replaced eventually, they will most likely be easier to change with this design, which makes it an important step forward for the internal combustion engine. If someone can make an engine that weighs ten times less than the engine it replaced for the same amount of power output, THAT says something and this should be looked into further.

https://www.liquidpiston.com/xmini

I may even invest in this at some point.

[gen3v8]

Originally Posted by Dzmitry

As NoHaveMSG said, you're just misunderstanding his point. The engine is near its peak, there isn't much to gain. E85 is like a cheat - not only is it not available to everyone, but you are putting in fuel that was never designed for the platform. If you consider the classic way of tuning, aside from going FI of course (which completely changes the characteristics of this car), you have very little to gain, even from removing both cats. It'll flatten your torque curve and give you some ponies up top, and that's it. That's in simple terms, obviously there is a nice little gain throughout the powerband, but not anything crazy. This was just a well designed engine from the start, hence the 205 HP output from a 2.0L N/A.

15-20% more ponies up top with a flatter higher torque curve is a great gain in some peoples eyes.

[Dzmitry]

Originally Posted by gen3v8

15-20% more ponies up top with a flatter higher torque curve is a great gain in some peoples eyes.

From just header and tune, or even a full exhaust (which most don't prefer or wouldn't do because of the smell or sound it produces), you will be lucky to get that % up top. Though header manufacturers and certain companies may claim these kind of gains (and they probably do obtain them or close to them), the general person on this forum that goes out to buy a header and gets a tune does not get such output. Take a look at many people on this forum as an example - many are disappointed in their gains or expected more. An 8-15% increase is far more realistic for most folks at peak. Not arguing that it's not a lot, but defending the point made by a couple people above coming from older vehicles.

https://www.ft86club.com/forums/showthread.php?t=70155
https://www.ft86club.com/forums/showthread.php?t=41525
https://blog.modbargains.com/fix-tor...r-ssubaru-brz/
https://www.ft86club.com/forums/showthread.php?p=938787

The above are just random links of examples, and even half of these are manufacturers posting their BEST results likely, and not an accurate representative of what most people that get a tune with a header actually get. E85 is where the greatest gains come from, and as I said earlier, I am keeping that out of the equation.

This engine was designed with some of the highest power they could come up with, including some cost savings and heavy emission guidelines. If they didn't need to stick a cat in the header, plenty of people that do some minor tune-ups now would be happy leaving the car as is.

[PenGun]

Originally Posted by PulsarBeeerz

There are many NA dyno results that refute those statements. haha E85 in particular loves that 12.5:1 compression. Also people have been running conservative boost setups on this engine for the better part of 7-8 years.

I take it you are new to the platform??

I have had the car for over a year. I built cars when I was young, I do know how this works.


I have possibly the best gas in NA for my car, Chevron Good Old Premium. No alcohol 94 octane goodness, so my computer pulls time, the biggest source of power loss in these cars, less often than some lesser fuels. I do understand E85 takes this a little further, but as many have said there really is not a lot left. Certainly boost changes everything, but boosting a 12.5/1 motor is not the best way to do that. Rebuilding it would be a useful way to add boost.


It all comes down to what the computer will let you do. Now I had trick stuff, a QuarterHorse for my Mark VIII, and could tell the computer all kinds of things. You cannot do that with this car, you need to get someone who has payed for the privilege to make you a tune.


As always YMMV.

[gen3v8]

Originally Posted by Dzmitry

An 8-15% increase is far more realistic for most folks at peak. Not arguing that it's not a lot, but defending the point made by a couple people above coming from older vehicles.

I said 15-20% My glass is half full @ 15% your glass is unfortunately half empty @15%. 15% of 205 would only make it 230

[Dzmitry]

Originally Posted by gen3v8

I said 15-20% My glass is half full @ 15% your glass is unfortunately half empty @15%. 15% of 205 would only make it 230

If we're going to do number calculations, it would actually be ~236 - and that doesn't change what I said, as a whopping 30HP gain is extremely unlikely on just a header and tune. You might be looking at around 10 for a typical off the shelf tune and maybe up to 15 from a solid revised E-tune. 15HP is a little over 7%.

I'm not here to pick a fight with ya, just saying that you shouldn't expect or give others expectations of those kind of gains. I bought what is known as one of the best headers on the market for this platform along with a cat-back. I also got Ecutek and a few revisions from one of the best tuners for this platform on the east coast. I even went to his dyno later on for the hell of it to get the experience and wring out a few extra ponies. End result was 178whp. Though I never got a baseline, I certainly don't believe I ever gained anything close to 30HP. It feels stronger up top, but not by much.. Keep in mind, too, that I went above and beyond what the majority of people here would do.