Will a B@M shift kit kit help/hurt MPG?

[BigTruckDriver]

I have a 89 suburban 350 TBI and was thinking about installing a corvette servo and a B@M shift kit for better performance and some towing. Will these upgrades hurt daily MPG?

[NEUMANNZZ]

nope.

[YenkoST]

No....these upgrades are only to firm up the shifts in the transmission...has nothing to do with the fueling of engine.

[BigTruckDriver]

So they only firm up the shift ? They dont change the shift points? I was thinking they might shift sooner.

[Kenny C]

So they only firm up the shift ? They dont change the shift points? I was thinking they might shift sooner.

Faster...not sooner.

[Whitebowtie]

Technically it could help your mileage, although it may be a very small amount. The reason I say this is because your shifts will be quicker and more positive. The way a stock Trans makes smooth shifts is by slipping into the next gear slowly. The shift kit will make this happen faster, so less time slipping and more time pulling forward. That's why drag racers install shift kits to help improve their quarter mile times. Also, a quicker shift will give less wear on you clutches and bands inside your Trans. As far as when the shifts occur, I think they stay roughly the same or maybe a little later.

[YenkoST]

So they only firm up the shift ? They dont change the shift points? I was thinking they might shift sooner.
It will only make the shift firmer due to more line pressure and as a result a quicker/faster upshifts. Shift sooner or later has to do with the governor.

[Fast305]

It will only make the shift firmer due to more line pressure and as a result a quicker/faster upshifts. Shift sooner or later has to do with the governor.

BUT, higher line pressure will delay the upshifts, especially at low-throttle.