2x6spds

Miata owners were pretty stoked when they purchased their variable timing 155 HP Miatas. Mazda now admits that it overstated the HP on the new Miatas by 8% and has offered to buy them back or offer extended service at the owner's election.

Wonder if Honda would do the same if it turned out that they overrated the S2000's crank HP? Honda rates our F20Cs at 240. Dyno testing shows 190-200 at the rear wheels. I can't imagine a more efficient drivetrain than ours and never could understand how we could lose 20-25% between the crank and the wheels.

Gotta hand it to Mazda for standing up to this embarrassing misstep.

2x6spds

Sev

Most s2ks have put 200+ with a few going as high as 215 HP.

Just the performance numbers show that our car is producing what its supposed to.

2x6spds

_______

Hi Sev

I'd like to think all of our S2000s could do the 1/4 in 13.6, but they can't. Clearly, dyno calibration makes it hard to generalize or to say what the range of reported HP results signifies. It may mean that all of our S2000s are putting out substantially the same HP and the variances are the result of different dyno set ups. But, it may mean that some S2000s are underperforming in the HP department.

Just a thought.

2x6spds

S2K_CLS

I posted this thread in off-topic, but no body responded

whats interesting is that in most cases, when you do VVT you tend to make the torque peak occur at a higher RPM...

Might explain why some magazines have tested the new Miata to be slower than the old...

I mean 2 more hp, but a higher RPM torque peak would explain a slower car... thats before you factor in the added weight of the newer Miata...


[QUOTE]Originally posted by 2x6spds
[B]Miata owners were pretty stoked when they purchased their variable timing 155 HP Miatas. Mazda now admits that it overstated the HP on the new Miatas by 8% and has offered to buy them back or offer extended service at the owner's election.

Wonder if Honda would do the same if it turned out that they overrated the S2000's crank HP? Honda rates our F20Cs at 240. Dyno testing shows 190-200 at the rear wheels. I can't imagine a more efficient drivetrain than ours and never could understand how we could lose 20-25% between the crank and the wheels.

89

The Miata dyno plots for the old and new engines were essentially the same. Basically the VV was just not working...

It's great that Mazda stood by their product, but kinda embarrasing for them nontheless...

DavidM

Main reason the 'new' MX-5s (Miata) are slower in magazines is because they need two shifts for the 0-100km/h (and 0-60mph). 2nd shift occurs at about 93km/h (58mph) which takes good 0.3 - 0.5 sec. The 5-speed MX-5s could do over 100km/h (62.5mph) in 2nd gear and therefore needed only one shift. Also, for the 400m sprint there is 'extra' gearchange needed. The car is actually quicker when moving but the 'extra' gearchanges are balooning the times to be slower than the old one.

I can't comment on the S2000's actual power but if people are reporting 200hp at the rear-wheels then I think that is pretty efficient drivetrain. 25% loss at the wheels does not sound too bad ... as far as I know 30% loss is a more common number.

2x6spds

Hi David

I didn't know that 30% loss was common. In that case, we're doing great. I read on the Legend site that folks with the 200 HP Gen 2, Type I engines were dynoing at about 175 HP at the front wheels. I figured that 12-15% was the expected range of loss, but I have no other info to have based that on. Also figured that the S2000 would have one of the most efficient powertrains out there, after all, a sweet little 6 speed, relatively firm clutch, etc.

I know that Ford had a problem with their Cobras making advertised HP and they came up with all kinds of fixes to bump the real world output of the engines sold. Mazda came out with the buy-back or extended service warranty alternatives. I was just a thinkin'

Thanks

2x6

pellisS2k

IIRC.. my 90 and 93 miatas redlined in 2nd at about 56mph. I know the ratios (at least the final drive) changed, but i think the overall gearing for the 5spedds has remained pretty mcuh the same throughout the years, always requiring 2 shifts to get to 60, and certainly to 100kph

DavidM

PellisS2k, you could be right about the MX5 2nd gear, though, I really thought that if you take the 2nd gear all the way to the redline (maybe even more 'cos the cutout was pretty high) then you'd be doing just over 100km/h (62.5mph). Though, I can't remember the exacly speeds in gear and couldn't find anything on it in a hurry. I did find this for an MX5 though:
1st 3.136
2nd 1.888
3rd 1.330
4th 1.000
5th 0.814
Rev 3.758
Final Drive Gear ratio 4.100
tyres 195/50R15

Can someone work out from that what the speed in 2nd gear would e (at 7000rpm)?

wickerbill

Legends are front-wheel drive. There is a lot less power loss with fwd compared to rwd. 20% to 25% loss is fairly common for a RWD car. I you think Honda overstated the power and you're basing it on dyno tests at the wheel, I would say 200 hp is within the limits of average power loss with a rear-wheel drive vehicle.

Mark