Why not 300+ hp?

[aliphian]

I just did some math, if this car ends up weighing 2,800lbs, then it will need 173hp to have the same power to weight ratio as an NB Miata. If it ends up weighing 2,700lbs, that number goes down to 167hp.
To keep up with the new Miatas, based on the above weights, it will need between 190-200hp.

I think we will be just fine.

[Archer256]

are we basing this on the assumption that TRD doesnt umm TRD-ify the engine?

[Dimman]

Originally Posted by Archer256

are we basing this on the assumption that TRD doesnt umm TRD-ify the engine?

TRD doesn't TRD-ify engines. They put a lot TRD stickers on other companies' parts these days...

Yamaha is who you want.

[Archer256]

Yamahaify
LFAify

[Dimman]

Originally Posted by Exage

The FB20 in its current state would need a stroke reduction and overbore (more square), longer connecting rods, and higher compression ratio if it's going to be a NA high rev engine. The 1.44:1 rod to stroke ratio is basically garbage for high rpm and bhp applications (both the late 2ZZ-GE and K20A2 had 1.62:1 and street bikes and racing applications can exceed 2:1, optimal is stated at 1.75:1). Even with revised intake and exhaust manifolds, heads, camshafts, and D-4S injection system I think the FB20 engine would take a huge compromise in wear rate at high rpm ranges in addition to the power increase to 200bhp without some altercation to the initial economy set up, this is more than just tossing in forged pistons and connecting rods. That's why I think we've heard basically nothing about this engine.

Exage, could you do me a favour and expand on this, as well as mean piston speed, and the g-forces on rods/pistons from the stroke and rpm in the Engine tech thread? I'm looking at going a different route with my car than the usual 'Add more boost' crowd. My engine's 86mm bore by 71.5mm stroke, screams RPM!!! to me. What kind of loads would be on the motor (and which parts of it) if I wanted to hypothetically hit 10k rpm?

Thanks.

[HachirokuDrifter]

Reminds me of the Lotus Elise. You don't really need that much power for a great car to drive. Remember, the FT86 is already resonably light, (but still, not that light either) so I reckon without much tuning or modifications this car could be a track beast, just like the elise, for less than 40k...just my 2 cents.

[SOB]

The Elise weighs under 2000lbs. This thing practically weighs a 1000lbs more.

[Allch Chcar]

Originally Posted by SOB

The Elise weighs under 2000lbs. This thing practically weighs a 1000lbs more.

The base elise is also over $40k and only 136BHP. <14lbs per BHP is respectable for a 4 banger at this price range. If you want more power cheaply you're going to have to choose a car with a bigger engine.

[Dragonitti]

Just for the record, I'm not speaking in terms of crank hp. If I said it's going to be 300 or more, that would be to the wheels. It would be balanced in all other areas to respectively harness the additional power.

[Ryephile]

Originally Posted by Allch Chcar

The base elise is also over $40k and only 136BHP. <14lbs per BHP is respectable for a 4 banger at this price range. If you want more power cheaply you're going to have to choose a car with a bigger engine.

Just because I'm involved in the Lotus world I want to set the record straight. The 136 HP engine was never available in the Elise here in the USA. The Elise started in the mid $40k's back in 2005 with the 189HP 2ZZge. If you want a brand new face-lifted Elise they now start at $52k with the same 189HP engine, and $55k for the supercharged version.


Your point still stands, however. More power = more price, that's how the automotive world works. The cheapest way to go quick right now for brand-new is to buy a Mustang GT 5.0. The FT-86 isn't about quick, it's about oneness, like the Miata.

[ichitaka05]

Originally Posted by Ryephile

Just because I'm involved in the Lotus world I want to set the record straight. The 136 HP engine was never available in the Elise here in the USA. The Elise started in the mid $40k's back in 2005 with the 189HP 2ZZge. If you want a brand new face-lifted Elise they now start at $52k with the same 189HP engine, and $55k for the supercharged version.


Your point still stands, however. More power = more price, that's how the automotive world works. The cheapest way to go quick right now for brand-new is to buy a Mustang GT 5.0. The FT-86 isn't about quick, it's about oneness, like the Miata.

He put BHP instead of HP

[Ryephile]

You realize there is no noteworthy difference between those two units, right?

Now, if he meant to say wheel HP, that's another story, because then we have to get involved in dyno brands and correction factors. Typical advertised [crank] HP [or BHP if you prefer] is done in a fashion resembling or conforming to the SAE J2723 standard.

[ichitaka05]

Originally Posted by Ryephile

You realize there is no noteworthy difference between those two units, right?

Now, if he meant to say wheel HP, that's another story, because then we have to get involved in dyno brands and correction factors. Typical advertised [crank] HP [or BHP if you prefer] is done in a fashion resembling or conforming to the SAE J2723 standard.

Yeah, sorry. For me, I meant to say "WHP" and not "BHP". It's lunch time here and nice weather & making me sleepy here so can't think correctly.

Thanks for the correction :happy0180:

[Dragonitti]

300 DynoDynamics whp (to be technical) will be pretty moving. The Gen Coupe 2.0T makes 382whp on a Dyno Dynamics with a GT3076r upgrade. It's a pig of car, so an FT weighing less making 300-350whp DDyno is a quick mover.