shift questions

phantom

Member
again.... need some advice. what is the best shift point of the MSP to do a quick launch???

when is best to shift from 1st to 2nd, and 2nd to 3rd etc??
 
will this hurt your 1st gear??? usually (for normal driving) I shift b4 3000rpm for 1st gear... coz' I don't know to hurt the 1st gear.... am I baby it too much??
 
if ur over 1000 miles dont worry about it, just dont make it a constant thing. U dont need to launch the traffic line every green light. I shift normally around 4500-5000 and 6500-7000 when I feel like getting somewhere fast ;)
 
wut about reving rpm high (3000-4500) b4 u let go of clutch and go from a stop?? (not from 1st to 2nd, i meant from stop to 1st)
 
will u rev up to 3500 b4 u shift from 1st to 2nd? like making a left turn from stop. would u stay on 1st until 3000rpm (when making the turn) and shift to 2nd after finished the turning? or I should shift b4 I'd make the turn?
 
i'm still learning myself, phantom. i just got back from my first actual practice.
i've been driving the car to work for the past couple of days, still learning as i go. when making left turns it really doesn't matter. you could shift to 2nd while turning or after you've completed the corner.

funny thing happened tonite while i was practicing, nothing big but i thought i'd mention...
i was driving kinda conservative and some stupid ford expedition was speeding fast behind me. we then stopped at a red light and he was behind me. when the light turned green i just took off slowly trying to see how smooth i could shift. the ford then switches lanes really quick and is along side me for a few secs, then takes off. i see him speeding past me and i wonder how powerful this car really is so i accelerate slowly just so i'm at his back tires. we were both going at about 60-65 in a 45 mph zone. i just thought to myself, "forget it..." and gave it a little more throttle and just passed him easily. as soon as i was about 2 car lenghs ahead i saw him slow down to about 40-45. i too slowed down and turned the corner into my neighborhood. i wouldn't really call it a race but just some idiot in a expedition acting stupid. i am impressed with the pull you get from this car. but like i said, nothing too exciting; just for me :(
 
I launch between 2800-3600rpm, try to feather the clutch while modulating the gas. You shouldn't get any chirping of the tires, just a good pull without wheelhop. The best thing to do is look at a dyno for your peak torque. This is where you want to be in a launching situation at all times, you want to maintain peak torque until your tranny/tires catch up to your engine.

Best way to test is at a drag strip, watch your 60' times, this will tell you how well you are launching. A good driver should be able to hit low 2.1's or 2.2's with this car. I know lawerence might be able to tell you what he hit on his 14.9.
 
Looking at the dyno numbers, you might want to shift a bit earlier than 6500: I haven't run the ratios myself, but you'll want to shift to keep between the torque and power peaks, and 6500 is well PAST the power peak....

I'll do some calculations later.
 
It's later.

I'm not sure WHAT the right answer is: If you shift at 6k each time, you end up at 3340 in 2nd, 4270 in 3rd and 4440 in 4th. Those are all past the torque peak, and the power starts at ~90 and builds to the peak at 150 at 5800 rpm (from the SCC dyno, BWT) and torque is dropping the whole time: from 145 in 2nd and 140 in 3rd or 4th at first, to 130 at the shift point.

On the other hand, by shifting at 6500 instead, you end up at: 3618 in 2nd, 4625 in 3rd and 4810 in 4th. The torque will be lower after each shif than with the early shift points, but the average power level will be higher (start at 115 in 2nd, ~135 in 3rd and 4th) if you look at the area under the curve.

I can't decide which is more important.... Probably torque.... in which case, the early shift makes sense, and perhaps even a shift point of 5800 (the power peak) makes more sense....
 
Does the car have a rev limiter? My gauge shows redline at 6500, but the revs climb from there. Haven't had mine over 6800 so far.

And is the rev limiter spark or fuel cut? If there is one (I'm pretty sure there is one, just don't know where it is and what happens when you hit it...)
 

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