Series I 4T60-E shifting
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Series I 4T60-E shifting
I debated this with many different people and am still unsure which yield better results (Gtech would be helpful)...
Allow the trans to shift while in D? Or go through the gears "manually" and allow the engine to wind out to 5500rpm each time before shifting? Which yields quicker acceleration?
Now I was talking to Boat and he said his 95 automatically shifts into 2nd at roughly 5800 rpm while keeping the shifter in first. I have allowed my car to wind out to 5500rpm but shifted it into the next gear myself. Someone please shed some light on this subject.
Allow the trans to shift while in D? Or go through the gears "manually" and allow the engine to wind out to 5500rpm each time before shifting? Which yields quicker acceleration?
Now I was talking to Boat and he said his 95 automatically shifts into 2nd at roughly 5800 rpm while keeping the shifter in first. I have allowed my car to wind out to 5500rpm but shifted it into the next gear myself. Someone please shed some light on this subject.
#3
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If I were you, I'd ease off the accelerator. If you are shifting at 5500 RPM out of first you:
A. Break traction everytime
B. Go through front tires like water
C. Have zero fuel effiency
On a hard accel I shift at 2500...easy accel usual about 2000, I never try to accelerate from a dead stop to force a shift at 3000. If I do that, I spin the tires like a crazy ****
Or am I missing something??
A. Break traction everytime
B. Go through front tires like water
C. Have zero fuel effiency
On a hard accel I shift at 2500...easy accel usual about 2000, I never try to accelerate from a dead stop to force a shift at 3000. If I do that, I spin the tires like a crazy ****
Or am I missing something??
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Originally Posted by 89BonnieSE89
The wolf in sheeps clothing. Gotta love it.
Hey, "**** Dog"...I get it now!
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Ok today I did some good ol' fashioned data acquisition by feel, touch, and thrill of acceleration. Heres what I got...
Chilton'* states:
L27 peak hp @ 4800 rpm
L27 peak tq @ 3200 rpm
Now this is what I discovered while leaving the car in D...
At 40mph @ 5000-5200 rpm the trans shifts into 2nd, then at 80mph @ 5100-5200 rpm the trans shifts again into third.
Now this is what I discover by "manually" shifting the car through 1, 2, and D...
At 45mph @ 5400-5500 rpm the trans shifts into 2nd gear, at 85mph @ 5400-5500 rpm the trans shifts again into third.
When leaving the car in D I notice the speedo climb very uniformally. When manually shifting the shifter it appears that I'm getting alot more out of the gear, but boy is that engine reving like a mother!
When the trans shifts up a gear at WOT the rpm'* drop to roughly 3800-3900 rpms. Now keep mind the peak hp is @ 4800 and peak tq is @ 3200. So by allowing the engine to rev higher by manually shifting isn't there a waste of time by losing all the torque which is way down there at 3200 rpms? This is just my logic coming into play here.
I could see with a stock L27 manually shifting would be better for drag because lets face it, a stock L27 will run roughly 16.8 seconds @ 82-83 mph. So that way you don't waste time shifting into 3rd.
In conclusion, the only way to see the real effects of this are to do many runs at the strip and the help of a G-tech...*cough* MN meet* cough*.
Chilton'* states:
L27 peak hp @ 4800 rpm
L27 peak tq @ 3200 rpm
Now this is what I discovered while leaving the car in D...
At 40mph @ 5000-5200 rpm the trans shifts into 2nd, then at 80mph @ 5100-5200 rpm the trans shifts again into third.
Now this is what I discover by "manually" shifting the car through 1, 2, and D...
At 45mph @ 5400-5500 rpm the trans shifts into 2nd gear, at 85mph @ 5400-5500 rpm the trans shifts again into third.
When leaving the car in D I notice the speedo climb very uniformally. When manually shifting the shifter it appears that I'm getting alot more out of the gear, but boy is that engine reving like a mother!
When the trans shifts up a gear at WOT the rpm'* drop to roughly 3800-3900 rpms. Now keep mind the peak hp is @ 4800 and peak tq is @ 3200. So by allowing the engine to rev higher by manually shifting isn't there a waste of time by losing all the torque which is way down there at 3200 rpms? This is just my logic coming into play here.
I could see with a stock L27 manually shifting would be better for drag because lets face it, a stock L27 will run roughly 16.8 seconds @ 82-83 mph. So that way you don't waste time shifting into 3rd.
In conclusion, the only way to see the real effects of this are to do many runs at the strip and the help of a G-tech...*cough* MN meet* cough*.
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I have a company who can help but it will cost quite a bit.
If you are a do it yourselfer I can sell a kit to you but really if you set up your transaxle properly regardless of who does it you can really get it cooking.
Limited slip hardened shafts are far from the end of the rainbow.
Ty
If you are a do it yourselfer I can sell a kit to you but really if you set up your transaxle properly regardless of who does it you can really get it cooking.
Limited slip hardened shafts are far from the end of the rainbow.
Ty