E85 On Stock 2017+ Cars Specifically

[86TOYO2k17]

Once you have 200whp, 100lbs weight reduction changes power to weight ratio the same as adding 7.5whp. Don’t sleep on the weight reduction.

[Irace86.2.0]

Originally Posted by 86TOYO2k17

Once you have 200whp, 100lbs weight reduction changes power to weight ratio the same as adding 7.5whp. Don’t sleep on the weight reduction.

Decent point, as long as you qualify that weight reduction isn’t just about power to weight ratio. If that were true then these would all perform equally (they don’t):

2800lbs / 200whp = 14.0lbs/hp
3800lbs / 271whp = 14.0lbs/hp
4800lbs / 343whp = 14.0lbs/hp

[Dr. BRZ]

My brz weighs 2460lbs from the stock 2776lbs and it does make a big difference. I also have lw accessories. I'm looking at removing an additional 70lbs. I dynoed at 205whp

[anticubus]

Originally Posted by Irace86.2.0

Decent point, as long as you qualify that weight reduction isn’t just about power to weight ratio. If that were true then these would all perform equally (they don’t):

2800lbs / 200whp = 14.0lbs/hp
3800lbs / 271whp = 14.0lbs/hp
4800lbs / 343whp = 14.0lbs/hp

This isn't even a valid comparison. Yes, each of those theoretical cars has the same peak power to weight ratio, and you're right, real world examples of those peak power to weight ratios aren't the same. The issue is that those real world examples have varied amounts of area under the curve. Given three engines tuned to make exactly proportional power to weight ratios at every point on their dyno graph, and without taking other things like friction and drag losses into account, you'd have the exact same performance from each.

Given those three proportional engines, and a weight reduction that is equally proportional to each car (Let's say 3.5%, so 2800 -> 2700, 3800 -> 3665, 4800 -> 4632) you still have the same ratio of 13.5, ignoring my rounding errors.

But this is all math, and the real world doesn't work this way. No two engines are exactly the same, and real world testing shows that the distribution of the weight and how that weight is sprung after reduction will be just as important as the weight itself, e.g. battery relocations in otherwise unchanged cars to shift the resting center of gravity. So again, you're right to say the weight reduction you choose to do shouldn't be entirely about power to weight, otherwise we'd all be driving FWD with the rear ends chopped off. I just don't think it's fair to give such a shaky set of numbers with no context in why they perform differently when a lot of those browsing aren't as interested in the math that goes into setting up a car properly.

And to lighten the mood, remember that Jeremy Clarkson proved FWD with the rear end chopped off is the ultimate way to show off your class.

[Lantanafrs2]

Same price as a twin you can buy a mustang with all the work done for you. With the twins its f.i or go home.

[j3rf]

Originally Posted by Lantanafrs2

Same price as a twin you can buy a mustang with all the work done for you. With the twins its f.i or go home.

Depends on the person and what they want out of the car.

[86TOYO2k17]

Originally Posted by Irace86.2.0

Decent point, as long as you qualify that weight reduction isn’t just about power to weight ratio. If that were true then these would all perform equally (they don’t):

2800lbs / 200whp = 14.0lbs/hp
3800lbs / 271whp = 14.0lbs/hp
4800lbs / 343whp = 14.0lbs/hp

Assuming they all made proportionally the same power/weight across the entire power band, had same gearing, and none where traction limited. Then straight line acceleration would theoretically be the same. And when looking at weight reduction on a specific car in and of itself all of those variables would be a constant as all your changing is weight.

[Lantanafrs2]

Originally Posted by j3rf

Depends on the person and what they want out of the car.

Chances are a lot of us will want more. Right now the Americans are offering better performance for same or less money.

[bfrank1972]

Originally Posted by Lantanafrs2

Chances are a lot of us will want more. Right now the Americans are offering better performance for same or less money.

Not all about numbers, at least for some of us.

[Yoshoobaroo]

Originally Posted by Lantanafrs2

Chances are a lot of us will want more. Right now the Americans are offering better performance for same or less money.

If you just want fast(fast-ish I guess), sure buy a 4cyl mustang. If you want fun, ehhhh. For fun it's this or the Miata.

[Dr. BRZ]

Yes but when a 4cyl import beats a v6 muscle, man, that satisfaction is great and the muscle guys always get so butt hurt. ��

[Irace86.2.0]

Originally Posted by anticubus

This isn't even a valid comparison.

Originally Posted by 86TOYO2k17

Assuming they all made proportionally the same power/weight across the entire power band, had same gearing, and none where traction limited. Then straight line acceleration would theoretically be the same. And when looking at weight reduction on a specific car in and of itself all of those variables would be a constant as all your changing is weight.

I was agreeing with your point, but saying that it should be made in the context of power to weight or straight line acceleration. The point I was making was that weight matters, and I think that is what the other guys point was too, that after 200whp power per invested dollar becomes not worth it, so focus on weight reduction, which is correct.

My examples were to counter the concept that ‘100lbs weight loss only equals 7.5hp gain, so focus on hp’, as if that is always preferable. In those examples, I would not trade 2000lb gain for the extra hp, even if straight line acceleration was maintained because power to weight was maintained. Why? Because I know 60-0 would go to crap, as well as, handling, wear on consumables, etc. Said another way, I would rather have three hundred pounds weight loss on my BRZ than an “equal” extra 22.5hp.

[Lantanafrs2]

Originally Posted by bfrank1972

Not all about numbers, at least for some of us.

If it wasn't about numbers we wouldn't be gutting our cars til they're 4 wheeled trashcans, hoping for an intake manifold to get us 10 horsepower, installing headers and tunes, arguing over lightweight pulleys just to prove a point lol

[86TOYO2k17]

Originally Posted by Lantanafrs2

Same price as a twin you can buy a mustang with all the work done for you. With the twins its f.i or go home.

I do agree FI is a solid option.
But
Ecoboost is 800lbs heavier and 22” longer. Much worse handling, and driver feel.
Basically looking at how much faster the ecoboost is, the 86 is that much better in handling and control.
So then you got to decide what costs more, making an 86 as fast as an ecoboost (although FI 86 is a lot faster) or making an ecoboost handle and feel as well as an 86?
And not to mention the looks. 86 > mustang can’t put a price on that.