4.10's / new shift points?

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I don't think that is necessary. If you modify something that changes the power band of your engine then you will have to change the shift points. For instance, if you upgrade your cams and intake then you will have to shift at a higher RPM because the engine will make more power at a higher RPM than it did before. If your car stopped making power at lets say 5,800 rpm stock and you upgraded to a cam and intake with a 2,200-6,200 rpm range, then you can change the shift point to 6,200 because now you will be making power up to 6,200 instead of dropping off at 5,800. Changing to a numerically higher rear end ratio does not affect where the engine makes its power so you can still shift at the same rpm as before. The numerically higher gears just gets you into your power band quicker. If anything, you will lose top speed because at any given speed you will be at a higher rpm. So for example, if you were going 150 mph in top gear at 5,800 where you power drops off, a numerically higher ratio will have you at 5,800 rpm at a lower speed but your power will still drop off just the same...it's always good to experiment tho as long as you're careful not to damage your car...
 
Chaning the shift pattern of an auto makes a huge change. I had a JMS chip for years that gave me firmer shifts with my 4.10s, shift points were adjusted for the gears but thats it.

For an auto I CANNOT RECOMMEND A SF3/XCAL3 ENOUGH. The shift pattern with the SF3 is so much improved over stock. Part throttle shifting is so much better. The car stays in the lower gears much longer as you accelerate out of a corner for example, and then you can mash it without a downshift.

Of everything I've done to my car, 4.10s and the SF3 are by far the best :nice:

If you have a tuner and a dyno chart its easy to see when you should be shifting. Look at the peak rpm you shift at now and look at the hp on the dyno. Then look at the rpm on the next gear immediately after the shift, and check out the power there. Adjust the shift points based on that, without over revving.
 
Automatics are electronic so they have a bit of a delay when you manually shift them. You have to time it and hit the shifter before you want the car to actually shift...if you can get a shift light then you can set it so it'll tell you exactly when to hit the shifter and then the car will shift at the point where you want it to...it takes practice but it's a crap load of fun...does anyone know if the factory shift points (rpm) are set back at all...?? If they are then adding 200 or so rpm to the shift point may give you a quicker 1/4 mile time...
 
With any gear change in an automatic you are going to want the shift points changed. Heck even with the stock gears a tune on the shift points makes a big difference. I still need to get a tune for my 4.10s and stall converter. I'm in 4th by 30mph.
 
I've got 3.73's and a 3500 rpm stall converter. I had to lower the 1-2 shift point down to 5200 rpm to get my shift to take place at 5850 rpm. with the gear change the revs climb so fast that the computer has a hard time keeping up. So yes you will likely have to adjust at least the 1-2 wide open shift point.
Lot of good advice here.