Change-Up Points for max accel (Leon 110)

[mik]

For what it's worth......don't have a dyno trace, so I'm using the only "fixed" data points I have available.....
173lbs.ft @ 1900rpm
110bhp @ 4150rpm ~ which equates to 139lbs.ft torque at this rpm.

Using these with the Leon gear ratios, I've calculated torque reaching the wheels......and for what it is worth...I can confirm that (for max acceleraion through the gears) you need to take the car to at least 4150rpm in each gear.

Although changing up takes you to a lower rpm in the next gear (where torque is higher) the change in gearing means a lower "final" torque at the wheels...hence slower acceleration.

It's difficult to see how much taking it beyond 4150rpm in each gear would assist without a dyno trace......but there is certainly no advantage in changing up earlier. It looks like it would probably be worth letting the car rev a little higher, but I can't be certain how much higher.....

New job Monday....so I won't have to waste my day calculating crap like this...... :rolleyes:

[Tdi 110]

Mik,

Yes, see your point, and agree if on the flat, but fact out weighs threory, and like I said in a different thread, I can pull that same max speed between 2 points (from say, 35mph start) whether I'm in 5th all the way from 35, or, in 2nd and taking it to 4150 in each gear........... I have how ever only tried this on 2 dual carridge ways and both have a steep uphil which leavels out until nearly flat it the top. Both hills obtain 100+mph at the top meaning that all gears are used in the "through gear test".

Then again, I haven't timed them, and although max spped may be the same, it might take shorter time when using gears??

[mik]

Weird ~ in 3rd @ 35mph you should have well over twice the torque at the wheels that you have in 5th at this speed.....so you should accelerate more than twice as quickly.

When you say "change gear" do you get out, pop the bonnet and do it by hand? ;)

When you get Upsoluted you can satisfy yourself that you have more torque from 1900rpm to approx 4300rpm than a standard Cupra......so you'll accelerate harder than one through this rev range (assuming your gearing is the same).

Of course the Cupra will carry on to 6K rpm in the lower gear and probably overhaul you.....but I really don't think your car will be that much slower.....

And then they'll go an get Upsoluted too......buggar....hadn't thought of that! :rolleyes:

Cheers,
Mik

[Tdi 110]

Well, the UPsolute chip certainly has made a difference.....I've added power graph etc in "Leon" section......Or will be any minute.....