Subaru BRZ Prototype Review by Car and Driver. Calls it a Knockout.

[Dimman]

I know if anyone really clued in to what I was getting at with BMEP.

Here it is simpler: Those output numbers are impossible.

Therefore the mag was guessing. Not arguable.

If they are guessing on that, they are likely guessing on everything else.

Zero credibility.

[Akai]

Originally Posted by Ryephile

^^I think you're confusing Euro advertised RON vs. USA "anti-knock index" [R+M]/2. 98 RON is approximately 93 octane USA.

o_0" Oh I see, hehehe thanks for clearing that up! No worries then....

[madfast]

Originally Posted by Dimman

I know if anyone really clued in to what I was getting at with BMEP.

Here it is simpler: Those output numbers are impossible.

Therefore the mag was guessing. Not arguable.

If they are guessing on that, they are likely guessing on everything else.

Zero credibility.

what 2.0L 4 cyl makes 170 ft lbs? i'd be happy to see 160+. these figures are pure conjecture.

in interviews they stated the weight goal was 1150kg or whatever, and now all of a sudden it balloons to 2800?

[Dimman]

Originally Posted by madfast

what 2.0L 4 cyl makes 170 ft lbs? i'd be happy to see 160+. these figures are pure conjecture.

in interviews they stated the weight goal was 1150kg or whatever, and now all of a sudden it balloons to 2800?

170 lb-ft is completely possible at 210 psi BMEP, about the same as the new Porsche 3.8L gets (less actually the 3.8L makes 211.7 psi BMEP at its torque peak).

It's the rpms that don't match up.

BMEP maxes out at torque peak and tapers off. The Porsche motor makes 211.7 psi BMEP at 5600 rpm. At its power peak 1800 rpm later, it has tapered down to about 90%.

For the mag numbers to make sense the FT86's BMEP can't drop after torque peak, which is impossible.

For it to make 200 hp @ 6500 rpm instead of 210 it would only be allowed to drop to 95% of peak BMEP over a 2500 rpm spread. This would be astounding.

Realistically I would say the 210 psi max BMEP (creating the 170 lb-ft) IS possible. But for it to make 210 hp with it dropping to 90% BMEP over, say, 2000 rpm (similar to the Porsche motor) the rpm numbers will be different.

210 bhp @ 7200 rpm and 170 lb-ft @ 5200 rpm (possibly as high as 5400 rpm) would be a more realistic guess for a 210 psi BMEP figure.

[KevinDuMa]

Honestly if the Hyundai Veloster can weigh 2600lbs, so can the Ft-86

[madfast]

Originally Posted by Dimman

170 lb-ft is completely possible at 210 psi BMEP, about the same as the new Porsche 3.8L gets (less actually the 3.8L makes 211.7 psi BMEP at its torque peak).

It's the rpms that don't match up.

BMEP maxes out at torque peak and tapers off. The Porsche motor makes 211.7 psi BMEP at 5600 rpm. At its power peak 1800 rpm later, it has tapered down to about 90%.

For the mag numbers to make sense the FT86's BMEP can't drop after torque peak, which is impossible.

For it to make 200 hp @ 6500 rpm instead of 210 it would only be allowed to drop to 95% of peak BMEP over a 2500 rpm spread. This would be astounding.

Realistically I would say the 210 psi max BMEP (creating the 170 lb-ft) IS possible. But for it to make 210 hp with it dropping to 90% BMEP over, say, 2000 rpm (similar to the Porsche motor) the rpm numbers will be different.

210 bhp @ 7200 rpm and 170 lb-ft @ 5200 rpm (possibly as high as 5400 rpm) would be a more realistic guess for a 210 psi BMEP figure.

its possible on paper, but i'm looking for a real life example of a 2.0L 4 cyl engine that makes 170 ft lbs in production form. anybody have examples?

Originally Posted by KevinDuMa

Honestly if the Hyundai Veloster can weigh 2600lbs, so can the Ft-86

yeah, the miata with PRHT and all the options weighs a little over 2600. how much crap would they have to add to the FT to make it 2800? not happening...

[ichitaka05]

Originally Posted by madfast

its possible on paper, but i'm looking for a real life example of a 2.0L 4 cyl engine that makes 170 hp in production form. anybody have examples?




yeah, the miata with PRHT and all the options weighs a little over 2600. how much crap would they have to add to the FT to make it 2800? not happening...

Like current Mx5? iirc that makes 170bhp

Also EJ204 engine (190hp)

[madfast]

Originally Posted by ichitaka05

Like current Mx5? iirc that makes 170bhp

Also EJ204 engine (190hp)

doh! meant to say 170 ft lbs.

[Dave-ROR]

Originally Posted by PAImportTuner

Ok let's keep it strictly a Dynojet then. Today's cars loses 12-15%.

According to this article and comparing it to the Subaru's internal conference a few weeks back the number is a bit off. What I'm saying is the car will make less on the Dynojet than expected at 210hp, like 20-21% less.

I guess my point was.. who cares

Dynos are good for tuning a car. I don't care what the actual number is and I only use dynos for tuning purposes.

I'm sure there will be people who care about the number though.

[Dave-ROR]

Originally Posted by Dimman

I know if anyone really clued in to what I was getting at with BMEP.

Here it is simpler: Those output numbers are impossible.

Therefore the mag was guessing. Not arguable.

If they are guessing on that, they are likely guessing on everything else.

Zero credibility.

I agreed and didn't see the point of replying :P My guess is Subaru threw out some vague numbers, and they "felt" that the power dropped off after 6500RPM, so they guessed. I guarantee none of them ever calculate anything, let alone bmep.

[ichitaka05]

Originally Posted by madfast

doh! meant to say 170 ft lbs.

Yeah, I don't think even EJ204 makes 170tq. S2k iirc was 150tq-ish

[Dave-ROR]

Originally Posted by madfast

doh! meant to say 170 ft lbs.

LOL you edited before ichi replied and I was thinking "damn ichi learn to read.."

[Dave-ROR]

Originally Posted by ichitaka05

Yeah, I don't think even EJ204 makes 170tq. S2k iirc was 150tq-ish

153 for the 2.0, 162 for the good motor :P

[SUB-FT86]

Even if it was to get 170 lb ft it would be accessible at a very high rpm I bet. Not 4000 rpms