Help me understand this...
Thread Starter
Drifting
Joined: Jun 2002
Posts: 1,406
Likes: 0
From: York PA
Help me understand this...
When I hammer my car in first, I look to shift around 4500 rpm. The power that the car is making in first is, to say the least, okay. However, when I shift into 2nd and even third at about the same rpms, the power just kicks in where you can really feel it let loose. Does it work this way because this is how my gearing is set up? I have 3.33's in mine (6spd). Don't get me wrong...the car runs like a raped ape; but not until second gear and onward.
Race Director
Joined: Sep 2002
Posts: 17,881
Likes: 25
From: The third orange grove on the left
Re: Help me understand this... (fast90)
My guess is it's the way the gearing is set up. First gear is a lot of power but not much speed. Second gear gives you less power but more speed, and so on. I'm not sure if it actually works this way, but that's how it "feels" to me.
Le Mans Master
Joined: Jun 2002
Posts: 5,357
Likes: 2
From: Moving forward, in reverse.
Re: Help me understand this... (1995LT1)
I belive it has a lot to do with gearing as well. Both in the rear and the transmission. Have you had your trans gone through? It could be the gearing of first in the actual transmission since it's only affecting the feel of fist gear. That's my thought.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Help me understand this... (fast90)
Sounds like you have a 6-speed; if so what's the 1 & 2 gearing?
Also, I think 4,500rpm may be a little low to throw the shifts. Take a look at the dyno plot on my site. The best trap speed is obtained from shifting so as to maximize the area under the HP curve. So you should shift past the max HP peak; you then realy feel the pull because you're further up on the power curve after the shift.
Other than using time slips, a good way to determine optimun shift points is to get a copy of Drag2000, put in your dyno curve (or one close), your gears, your tranny and experiment with the shift points to see what effect it has on trap speed and ET.
Also, I think 4,500rpm may be a little low to throw the shifts. Take a look at the dyno plot on my site. The best trap speed is obtained from shifting so as to maximize the area under the HP curve. So you should shift past the max HP peak; you then realy feel the pull because you're further up on the power curve after the shift.
Other than using time slips, a good way to determine optimun shift points is to get a copy of Drag2000, put in your dyno curve (or one close), your gears, your tranny and experiment with the shift points to see what effect it has on trap speed and ET.
