The Ol' Engine CC/Tranny Ratio Song and Dance

[70bus]

I've dug through seemingly all the tranny articles, but would appreciate opinions on my specific options. 65 s/c. Big nut stock trans/RGBs needing a rebuild.

Motor options:
I have a 1600 SP in my '70, 69mm CW crank, stock cam. 30P3 carb and 205 something dizzy.

I have a spare Mexican universal case, stock, but it was last .040 and might need cut to 60. I have a pair of 211 '1500' heads appropriate for the truck.

I have an aluminum universal case, bored for machine-in 88s, full-flow, 69mm CW crank. SP heads. Think it was 1960cc or so. Also stock carb/diz/cam.

Tranny options:
Stock, or 3.88/82 Freeway Flyer. I have a NOS 3.88 R&P if I go that way.

Variables:
I prefer SP heads for torque. Have plenty of SP parts; no DP ones. I live on a hill which has a 25-degree slope nearly the whole way, and portions exceeding 30. I rarely drive on interstates, but it's sometimes necessary. Almost all roads in my state have hills, and some gnarly ones at that. Not looking to dump money on strokers, or dual carbs (tho would consider a 72 crank if stock carb is doable with it).

If I throw in a 1500 or 1600, various threads suggested a Freeway Flyer ends up being a dog with those engines. Stock tranny is great for hills with them, but a little slow or maxxed fan on highways. If I put in the AL case with stock gearing, I'm thinking I get a little more oomph on the hills, but unsure if I get slower fan speeds/higher street speeds. I do not need to do 75 mph, especially in a car with lap belts. The '70 has 3points AND disk brakes, so there's an argument to put the AL case in there as the safety features can handle the extra speed, and put the 1600 in the truck. It sounds like I am best keeping the stock 65 tranny ratios, and can then use any of the 3 motors I have/can build. Going w/ a FF likely means I am using the AL case, but it's unclear if I gain too much advantage to do so.

Thoughts?
_________________
Craig K
70 Neunsitzer
65 Pritschenwagen
"If Von Dutch was alive, he'd walk in there with a pistol and shoot these people." - Robert Williams

Raul the 65 singlecab

Karl the 70 nine-seater

[David Raistrick]

E&B like their 1641/3.88/82/big nut combo.

honestly if you're not getting into 4th, it's really not going to matter a ton. 1st is going to have tons of room to get you and keep you going no matter what's behind it.

isn't that 88x69 a 1679cc or something? didnt you used to have a 1776/3.88?


here's a stock big nut and a 4.12/82, 3.88/82, 3.88/77, and 3.44/77. and some bay/vanagon gearing to compare (colors are still based on upright fan, not t4 fan). [edit: corrected rgb gearing, thanks tom for point out my brain fart]

color bands are cooling related - 2800 is reportedly the best fan range. 1500 min rpm, 3600 it starts to cavitate

keep in mind a 1600 is going to be working a LOT harder at 2500rpm to keep a bus chugging in 4th than say a 2L would be.

_________________
...david - '66 SO-44 #231

[70bus]

Sorry, yes, 1680cc on the ALfromhell case seems right. That.s the only motor I’ve run besides a 1600, and both in the 70. The AL seems to hold the heat longer, but the extra cc may mean it isn’t making it as much as an overworked 1600 at speed to begin with.

With our hills, I don’t want to be screaming the motor in second just to get to top. That’s my concern w/ higher gearing. I guess I need 2 transmissions to test out each possible combo. LOL.
_________________
Craig K
70 Neunsitzer
65 Pritschenwagen
"If Von Dutch was alive, he'd walk in there with a pistol and shoot these people." - Robert Williams

Raul the 65 singlecab

Karl the 70 nine-seater

[Lind]

[70bus]

I'm going to guess that's either an attempt at sound advice, or your usual dry humor. :)

It's a hill the spandex bikers use to train on, by lugging up it foot by foot, throwing up at the top, and then coasting back down. There's a race that sadistically paints the actual slope of each stretch on the pavement.

Always fun to watch the automobile fun in winter.

So yes, I want to get up it. But I think I need to drive in non-alpine zones as well, so I'll keep the stock RGBs. Some people have bad experiences w/ FF and 1600 or less motors, some don't. I'm mostly trying to decide if I get enough extra zing out of the 1680 to make a FF worth it, or if the extra CC make the stock ratio livable at higher speeds.
_________________
Craig K
70 Neunsitzer
65 Pritschenwagen
"If Von Dutch was alive, he'd walk in there with a pistol and shoot these people." - Robert Williams

Raul the 65 singlecab

Karl the 70 nine-seater

[Lind]

Anything higher than stock gearing will not be enjoyable.

25+ degrees is crazy steep. They literally made special gears for people that have to drive roads that steep. Of course those gears make it undriveable on the highway. Stick with stock gearing and a bigger engine and you will be fine.
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Wanted:
Idaho VW license plate frames or other dealership items.
VWoA literature and early dealership or distributor literature/pictures/information
.

[70bus]

I checked a few places, and the 'official' grades range between 8 and 23 for most of the streets. Long story, but we had measured sections with a 3' digital level and got the higher figures.

But yes, my main concern is getting home rather than going 75. Thanks for the input.
_________________
Craig K
70 Neunsitzer
65 Pritschenwagen
"If Von Dutch was alive, he'd walk in there with a pistol and shoot these people." - Robert Williams

Raul the 65 singlecab

Karl the 70 nine-seater

[Clara]