Shift kit on ls1?

[Miickyy]

Ey peeps. Just wanna know whether a shift kit and servo gears is really worth the money considering they Vx ss is and electronic box. All the adjustments are made through the tune so is it even worth having them and what are your recommendations

 

[Jxfwsf]

There is a limit to how much you can mod the line pressure in the tune. A shift kit is not so much changing the shift points, couple of holes drilled bigger in the valve body separator plate to increase line pressure and stronger springs in the accumulator pistons (or no springs and lock them) to firm up shifts. Even if you bumped the line pressure in the tune it still has the soft stock springs so changes may still be soft although once in gear has the higher pressure.
Corvette servo increases the size of the pistons that hold the 2/4 band in place, more surface area = more holding pressure.

A tune after the shift kit is installed is just icing on the cake.

 

[Miickyy]

What about performance wise I'm looking at tryna get that car to climb that speedo quicker.

 

[Immortality]

A shift kit will improve performance around the transmission shift points (less slippage) but ultimately if you want to accelerate quicker you either need more power or make better use of it. The single easiest way to improve acceleration is fitting a set of diff gears.

Factory LS1 + auto has 3.07 diff ratio. The easiest upgrade is a 3.46 complete diff from a manual LS equipped model. Better still would be either 3.73 or 3.9 gears or 4.11's if highway cruising is of no concern.

 

[Husky]

I have a shift kit in my daily (V6). if my VUSS wasn't a manual I would get a shift kit in a heart beat. They make the box much much better.

 

[WHCapriceHBD]

I've had the auto in my WH altered via the tune a couple of weeks ago- I had the line pressure increased and firmer harder/faster shifts whenever the Power button is pressed. In standard (non-Power mode) the shifts are still soft. Also had the PCM modified to kick down earlier than stock. This gives a more willing feel to the car overall.
Its pretty awesome. The fast downchanges are great for overtaking when you need it.

Also had the semi-auto function added so it will hold 1st 2nd or 3rd when the stick is moved into that gear, and will hold the gear to the limiter without shifting up.

One of the best bang for buck mods you can do to the 4L60E in my opinion is a shift kit or PCM edit, as the increased line pressure and firmer shifts means the clutch packs grip quicker and do not wear as fast as in standard slow shifts- firming up the shifts actually increases transmission life. This is why many USA taxis used to get the old "B&M Shift Kit" added back in the day- taxi operators knew that less clutchpack slippage generated less wear and heat and the trans life could be extended for a few years extra- important cost savings across a fleet of taxis (imagine replacing 6 auto trans in 6 taxis in 6 months..)

I would not add a mechanical shift kit plus a PCM edit at the same time though- you may end up with too much line pressure in the valvebody and blow something. I would always get the PCM software changed, and add mechanical "helpers" like stronger accumulator springs.
I've been informed our LS 4L60E already has the Corvette servo gear inside them- so that may be fine to stay as is.

 

[Miickyy]

Hey guys so I manage to get myself a 3.45 diff in the bum of my Vx ss and made a solid 235rwkw prior to the diff install. The car was fun with the auto diff but now with the manual diff on the a4 box wow snapping gears and chirping through like I had cheese cutters on there lol. Now I seriously want to firm up those shift points and here more of those chirping sounds any one recommend a kit and a link to what is recommended ..