Gear Vendor
Did your shifter end up in the same location in the 4 speed hump or did you have to modify the hump? This part wasn't clear to me when reading on the gear vendors website. Thanks.
No mine didn't. The GVOD comes with a long tail house like on the B/E bodies. I had to purchase a long MS to make it work.
The front mounting point cannot be used as it sits right in the cross-member, and in fact, I had to grind a portion of the mount off so the adapter would fit in there. That leaves you with having to use the rear mount. At the time I got mine, nobody mentioned an adapter plate, so I made my own. That gives you an opportunity to put the shifter anywhere you want to. I chose waaaay back and waaay up,between the buckets, and then installed a really short stick. I love it.
As for splitshifting, the only box that this works properly on is the od box. The ratios are;
3.09-
2.41-1.67
-1.30-1.00-.
78/.73od-
.54double od. GV in red. Splits are
.78-.69-.78-.77-.78-.73........... So you get
Seven useable ratios.
There are a few problems with this.
Issue #1
with street tires, say 27s,there's only one rear-gear you can use to get three ratios to rpm-peak at 60 mph. Say your cam peaked at 5400. To hit 60 at 5400 in the third-ratio of 1.67 would take ~4.30s. BUT, that gets you a starter gear of 13.29. Which,IMO, is insane. I drove my combo like that for two summers, and said enough!
Issue #2
Double od makes 65=1875. So any cam bigger than ~223*.050, is gonna be hard to tune for economy, and will be operating in a poor efficiency zone. But using .78 overdrive, the Rs climb to ~2700, so kindof not what you want either.
Issue #3
The much much weaker .73od will get you ~2530, which is good, but when you put it into .73od with a badboy clutch, you gotta remember to take it real easy; so you don't shatter it!
Issue #4
a nice starter gear might be 11/1, and that would be 3.55s, and you can guess the rest. So in the end and after breaking two of those od gears, I jumped ship.
There is another option; the Commando box with ratios of
3.09-1.92-1.40-1.00 - For a description of this , see my signature below. I've been running this now since ~2004. With 3.55s and 27s, this cruises at 65=2240. My 230* cam seems to be ok with this but likes cruise timing of mid to high 50s; and there-in lies
issue #5.
With power timing of ~24* @2250; (14initial+10 in the flyweights), plus a modified Vcan timing of 22*, this gets you just 46* total cruise timing. Couple that with a cam that has a very short extraction period, and a lot of overlap, and you have a recipe for horrible fuel economy that is impossible to cure . Throw low-compression into the mix, and, the very reason you probably bought the GVOD, is now questionable.
My cure was a stand-alone,dial-back,dash-mounted, timing delay box that has a range of 15 degrees. I set it so that I can dial in the missing cruise-timing. And that introduces
issue #6
What happens if you forget to dial it back out when you come in off the hiway? With 10 to 14 extra degrees all the time, if you nail the gas, you could be buying pistons again real soon.
The good;
With a .78 split, the rpm drop from 6200 would be to 4850,just 1360rpm, and there is no good reason to run any LSA bigger than 110. If there is another cam in my future, I think I'll try something like a 106, maybe even a104. With a tighter LSA,headers, and the short powerband requirement from the trans, you can back off at least one camsize. I dropped three.
My 3650# tank felt real good with the 367 and a 223* cam, and was into the twelves on it's first and only run, with 3.55s and 245/60-14 streets, spinning a long long way.
Other than that, and what others have said, I really like my GVOD.
But if I had more money, I would get me a proper 5 speed. Cuz if you back up just 6 inches with the GV engaged; oh Snap! ......... If you do it twice, you coulda had a TKO.
