Indecisive me again.
I may have an opportunity to get a hold of a Vitara 3 speed auto for cheap, (The start to any great idea!) but I have some questions.
To start off, I know these are a bit of a compromise compared to something like an AW4, but I'm fine with that. (maybe) I just want an Auto... without the effort of an AW4...
So, gearing: The lack of overdrive is the obvious one. I spent a bit of time with a gearing calculator and I'd be running roughly 3900rpm at 100kmh (31's, 4.9 transfer, (maybe 6.4* which are 1% lower) and 3.7 diff gears) which is high, but I think manageable. I've been doing stints on the highway in 4th gear to simulate 1:1 ratio and I find it bearable.
*I'm not sure what transfer ratio to run. I ordered 6.4's recently because I was set on this car staying manual (
) But I'm not sure if it will be too low in low range with an auto? The tall first gear of a trimitic puts crawl ratio at 43:1 with 4.9's or 56:1 with 6.4's. That seems pretty reasonable, considering crawl is 66:1 with 4.9's and a standard manual, but I'm not sure how that will feel with an auto - On paper I think 6.4's should be sweet, even with 31's? The 1% extra reduction in high range obviously isn't ideal but it's still under 4k rpm at highway speeds. Here's the thing that might make this entire idea a bit silly: I want to put it behind the standard g13a, just for simplicity reasons. Is it just going to be a giant sluggish doughball of a thing? I had a g16a converted sierra before (the motor these auto's come behind) and I wasn't overly impressed with it compared to the g13, so I'm thinking it might be okay.
The floor work, jackshaft shortening doesn't worry me. I think a lucky 13 adapter (or make something) sorts out bolting up the gearbox. A closeout bush for the jackshaft. Simple Reverser light wiring etc..
Do these have front driveshaft clearance issues like the AW4 with no bump stop spacing?
Anything else I should know?
I'm basically looking for the simplest way to get an auto in the car, but still be able to drive it to tracks. Thoughts welcome.