opening up the Fiesta - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Mitch_lx · 12-19-2004, 04:04

As pieoter's dyno run shows power starts levelling off at the 4000RPM mark, whilst the website says it runs out of puff at around 6000rpm.
I think once an exhaust is fitted and proper intake, this little beast is going to continue making power untill the 6K rpm mark, im guessing the absolute PEAK power is going to be at about 5,500 then trail off towards 6 thousand rpm.
Opinions??

Pieoter · 12-19-2004, 04:18

There is some very nice power being made early on in the rev range meaning that low down torque is great as it is. But once 4000 is hit(peak torque) power is increasing very very slowly(only gain about 4KW in 2000revs) showing that torque is dropping off very quickly. All this gives the car very nice drivability but lowish performance(expains why short shifting at 5k doesn't realy lower peroformance).

A intake and exhaust will help but im thinking the main restriction is the cams. To pass EURO IV emmision the engine can have very little overlap meaning the cams can't be too agressive and as a result performance drops. This would also explain why the new 1.6L with VVT on both cams has an extra 10KW with no real increasein torque.

Exhaust and Intake are a must do for performance and I would look at fitting new cams or even better seening if the new head with dual VVT can somehow work on our cars(coming on new focus). Dual VVT with lumpier cams would be the ultimate system to have but would cost $$$.

My 2c.

Timmeh · 12-21-2004, 14:11

Don't forget, to maximise your gearshift, you need to go past your engines peak power before changing gears, so that you don't drop away from it too much on the gear change. This applies to any manual car. The other thing to consider too, is how fast the power is dropping away. If it slowly drops off, you can hold it out another 1,000rpm. If it drops off sharply at say an extra 700rpm, there's no point holding on past that.

Tim

Trevski · 02-04-2005, 08:28

Chuck it on a dino, getta torque v rpm curve. Note what gear the curve was taken in. Remember that torque is multiplied by gear ratio. Use torque/(gear ratio*final drive ratio) to get an actual flywheel torque curve. Use flywheel torque*gear ratio*diff ratio to get an actual road wheel torque curve for each gear. The figure given will already be reduced by gearbox losses, coz that's the way you measured it (well, approximately, actual losses will vary from gear to gear - hard to be precise unless you use the dino to geta torque curve for each gear). Draw a graph of road wheel torque v road speed, overlaying all 5 graphs for each gear (for a 5 spd manual). This will show you when you are really making more torque in the higher gear. Always remember that power is fantastic, but torque is what turns the world. Take note of the engine speed at which the car will make equal torque in the higher gear. This will differ for every shift. This is your theoretical shift rpm for each shift. Realise that your engine did an hand grenade 2000 rpm ago. Welcome back to the real world, shift at the redline. Bugger.

Mitch_lx · 02-04-2005, 16:42

bit too much trouble for me lol.
I launch at around 3,500, ,launching at these revs quick does chirp the wheels a bit.....and shift at around 6,300 lets off a nice big loud chirp aswell which is a good sign i guess lol.

Mitch_lx · 02-04-2005, 16:44

What are all your driving styles??

P.s thats not how i drive all the time, i drive like that maybe for 30 seconds and once every couple weeks lol. I like my engine and tyres in one piece.

Teki04 · 02-04-2005, 18:02

how can you not rev the fiesta? Its a willing engine, and wants to be heard... usually i drive to like max 4000rpm through each gear (max torque), but occasionally it sees red line. In regards to tyre chirps, when i first picked mine up with the zetec original 15 inch rims, i could do chirps, but with my 16 inch rims with Falken Tyres, i cant do it as much... too much grip

Mitch_lx · 02-05-2005, 04:30

Have you found that 16s slowed the car down much??? im expecting to feel a big (bad) difference when i have 17s on. going to have to get really low profile tyres.

Teki04 · 02-05-2005, 08:13

downside to 16s over the 15s, are that the car is a little slower, although take off i guess is better, it grips to much for second gear... AND you feel bumps more, BUT the steering improvements are soooooooooo worth it. Tyres go along way though, as my Falken Ziex512 have steel reinforced sidewalls, which make it handle more, but feel bumps more, with less absorbing in the tyres. Hence why i might get the Continentials or Goodyear F1s, which hopefully have a combination of absorbing bumps, and steering hard.

Mitch_lx · 02-05-2005, 16:57

dang i wana see what 17s are like :(