I have the GearVendor. It works best on the 3.09/direct box. Around town I shift 1-2-3-3od-4od; the ratios are 3.09-1.92-1.4-1.09-.78. The splits are; 62%,73%, 78%,71%.Purty nice.
But it gets better; For 1/8 mile, I shift; 1-1od-2. the ratios are 3.09-2.41-1.92.The splits are 78%,80%. SWEET. I run 3.23s out back. Goes 93mph at 7200rpm.Or if Im looking to ET well, I will regear the back to 4.1s and use 4 gears; 1-1od-2-2od. The ratios are 3.09-2.41-1.92-1.50. The split %s are 78/80/78. And 93 is 7100. Oh yeah.
-Now I havent yet run the 1/4. But if I was to, Id regear the back to 4.56s and shift; 1-2-3-3od. The ratios are 3.09-1.92-1.40-1.09. the split %s are 62/73/78. this would get me 115 at 7200.
-Around town I run 3.55s. this gets me a 10.97 starter gear, and a 2.77 cruiser gear.
-To say that this combo is flexible, is an understatement. The unit shifts faster than I can,probably faster than anybody can.Certainly faster than any automatic.
-There are two downsides;
Downside 1) The unit relies on driveshaft rpm to make its oil pressure which it uses to make the shift. If you use the supplied mini controller, this is not an issue.That controller has one important feature. If you connect it as described it will prevent the unit from engaging in reverse.The GV must absolutely not be engaged in reverse.This system was designed to be an overdrive. To that end the controller has a feature I didnt like. It seems to have a waiting period if you select it too early.Thats the first downside.
-That controller is too slow for drag-racing.To overcome this,I hooked the GV directly up to a button on the top of my shift ball.Now it shifts instantly, provided it has oilpressure. You now are the controller.
-If the d/s rpm is too slow when you call for a shift, then the shifts get mushy, and theres nothing you can do about it. Furthermore head-office was not forthcoming about that at time of sale.This is not a problem with the 3.55s and the 3.09box. This gets you 22mph at 3000 rpm, which I suggest to be the minimum spd to split. But why bother, I just use 2nd. With 3.23s the ds rpm comes up pretty slow, so I have a higher minimum road speed.
-At 4000 plus rpm with 3.55s theres plenty of oil pressure to perform a neck snapping shift. So under Wot, over 4000, its never an issue. Now here it comes;
-Downside 2); Are you going to remember to be sure the unit is not engaged in reverse? Thats a lesson that cost me a lot of money. To prevent this I installed a light on my dash to indicate engagement. And I religiously check it every time I grab reverse. Really I should rig a relay to the reverse light sw. but I havent yet.
-There are other things; GV will not sell you any tools or parts or extra adapters for it . If you want to put it onto something else, you must return the current adapter in exchange for another. It requires a special, expensive oil.I think it weighs 23 pounds.Thankfully the weight is in a great place.You can purchase it as a stand alone unit.That would require 2 driveshafts; one in and one out. In an 108inch A-body it would be a tight fit and would leave the working pinion angle very poor, if workable at all.
-Would I do it again? probably not. Passons has a 5speed coming. 15 years ago the options were Richmond, and DougNash. Both pricey. Both need pricey support works. And limited resale.The GV can go anywhere, almost.
-The GV also works well on the Mopar O/D box, but the very wide 1-2 split in that box makes it almost mandatory to use the GV there. And with 3.55s theres just not enough d/s rpm to pull it off.I ran that combo for a couple of years with 4.30s.Problem solved you say? not so fast. The starter gear was 13.29; too deep for around town. Start in 1od you say? Well good idea. but the GV will not hold o/d through a traffic light, and slips on take off.That cant be good for it.
-The other Mopar boxes can be used if you treat the GV as an overdrive only.The ratios are just too tight for the GV to be an advantage.
I guess I should mention;
Downside 3); you cant downshift into the GV. Its strictly an upshift thing.So the o/d box didnt work that well. The double o/d feature was great on long trips to far-away places.
-So there you have it. I think I about covered it all.Did I mention Passon Performance is working on bringing a 5 speed to market. There is a waiting list.You might want to look into that. It will really wake your small-block up.I can totally imagine it in a 408 with a small cam and street-friendly gears. Or going the otherway, behind a teener with a mild,223*cam and some decent compression. Either way, fun.