I wouldn't put a shift kit in,,,you wont like it and will probably drive like your Z did.
This it what all the Lightning guys go with.
A valve body. It will shift quick and hard when your heavy on the gas and you wont hardly know it's there during regular driving.
http://www.factorytechtransmissions....TS&Category=13
Only thing is you'll need to set your torque modulation back to the stock settings when you install it.
What blower are you running?
Phil
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Built Lightning block.
Stage 3 Ported heads. high performance Cams
Kenne Bell L upgrade blower 16 PSI
DMR Cog belt system
Kooks long tube headers
BTS race built 4R100 tranny
100 shot of nitrous
best 1/4 to date.
60' 1.68
11.76 @ 116.17