So to maximize performance should I run it all the way to 7500, or should I short shift it?
It feels to me that after 7200 the car is not really alive.

Your thoughts.....

 

I've noticed it, but haven't done any real testing to see which way it works out best. You could probably look at the actual torque being applied to the wheels (based on transmission gearing/multipliers) to see if shifting up at that point gets more/less torque to the wheels with the next gear.

 

This is a frequent question in the drag racing forum. Redline every gear. Kind of. If I get serious tire spin in first gear, I might short shift to second. More important than perfect shift points is how far does the RPM drop between shifts?

 

There are generic answers but each car's tranny and engines are a little bit different. The best way to really find out the optimal shift point for each gear would be to put your car on a dyno and see where the HP/Torque drops and in which RPM. Once you have your dyno sheet, you can see exactly where to shift for each gear when launching. Redline doesn't always mean most efficient. As most engines, the HR revs up to 7.5k RPMS but power may drop off, for example, as early as 6.8k RPMs. If this is the case, then taking it to 7.5K RPMs would make you slower as power would have left several hundred RPMs and "X" seconds ago.

Dynos are expensive but if you are really interested in competing to a point where hundredths of a second count...it'd be the best indicator.

2 cents.

 

I'm breaking traction and causing unwanted burnouts and drifts if I shift to second with more than 3k rpm. The rest of the gears seem pretty safe though going into with high rpms. Then again... I got a Base so no TCS or VDC. I've just gotta know where and when to do what (and what not to do). Racing through an intersection trying to beat a yellow light while making a left turn is a recipe for disaster for me though. I guess I'm just used to driving slow cars.

 

Yes. It is.

 

lol no its not. Hell thats where rwd cars shine. As long as there isnt understeer and the backend walks away on you youll be fine.

 

tires provide a certain coefficient of friction (depending on temperature, type of rubber, etc). The thing is, once it is broken... it's much easier for it to stay that way, it effectively comes down once they're already spinning/sliding.

These cars certainly have the power to break it easily, but in general they're not going to unless you're slamming the next gear, or stomping the throttle. Smooth shifting and application of power go a long way in keeping things "inside the line". Of course if you're doing it over a less than optimal road surface, the rules change again....but those are the kinds of things you just have to pay attention to.

I think the only "disaster in waiting" is not being aware of conditions and making adjustments as necessary.

 

Well here's what happened to me the other day... I'm at a double left turn waiting for the green in the outside turn lane. In front of me is a H2 and I'm the 4th car back. Light changes and we start moving, and the asshat driving the hummer decides he's in the wrong turn lane. So he's waiting for the inside lane to clear to bust his U-turn and is merging into it and out of mine, very slowly. By the time he's cleared the lane... I can finally see the light and it's yellow. I (like a dumbass) decide to make the light. I'm coming from a crawl in first... make it through the crosswalk, shift to second and... the whole back end just about comes undone. I'm making more of an effort now to shift to second at 2500 rpm now. And no more beating yellows. Lesson learned.

 

So were you actually turning when you shifted, or still in the turn lane?

 

turning when shifted... ;p

 

I'm thinking you may have missed my point. My point was that racing towards a yellow light will, undoubtly, lead to hazardous conditions...nothing about RWD, FWD, AWD, etc. The whole point is...DO NOT RACE TOWARDS YELLOW LIGHTS. Feel me?

 

This is such a common misconception.

Only because the engine makes most of its power at, lets say 6.8k, does not mean that shifting at redline [7500] is going to be a waste or be any less efficient.
That would only be true if after 6.8K, power drops to 0 or anywhere near it. An engine such as the VQ35DE & HR make a ton of power until redline, even though it drops significantly after 6.8k.

It's not just a "theory", its a fact. I've tested this out on the track, and trust me, I get much better results when shifting at redline.

.

 

1st and 2nd at redline, 3rd and higher I shift just before redline.

 

ditto.. but I can't say that I've redlined in 4th. I'm scared I'm going to get pulled over. When I go all out from a standstill, I'm going to have it on camera.

 

I'm only shifting like I said at a drag strip. Top of 3rd your doing 90mph, which is not exactly legal.

 

If your gas is good, it runs very strong right to redline, where I shift.

I have noticed a little KR with gas that wasn't quite as good apparently, but with my usual BP 93, no backing off, and it seems to be getting stronger with miles.

 

You are over 100 in in the top of 3rd, in the 07.

 

AT's have been breaking 100 in 3rd since '03.

 

Redline the car all gears and not really spin the tires....

1st gear i just let it ludge forward a little and ease it down faster and faster (best way to get exelent accel. without burning clutch or spinnin tires)

shifting to 2nd gear at redline will chirp tires and kick sideways, but not so much violent

EDIT: with VDC OFF and stock wheels/tires on a 07 touring