350 and 3 on the tree?

[71Longbed]

i was wondering how well this tranny works with a 350 and wut kind of mileage you guys get on it?

[Tx Firefighter]

I've run this combination several times. It should get pretty much the same mileage as a turbo 350 or turbo 400 would.

Top gear on the 3 speed it the same 1 to 1 as any other non overdrive transmission.

Physically, the transmission works well with a 350. Just make sure you have good linkage that shifts well and you should be pretty happy with the results.

[Nima]

I have a 67 with 350 and 3 on the tree. It came like that when I bought it few months ago. To me, it works great. I can't tell you about gas milage since I have not measure that yet. i don't drive it that much.

[1978steven]

My '71 has the same setup from the factory. I have been thinging of going to an automatic but I really like this setup. It still has the three on the tree and works very well, nice and smooth into all the shifts, no snaggs. I also really couldn't tell you what kind of mileage it gets because I never fill the tank completly full. I drive mine everyday and have no problems with it. When I bought the truck the engine and tranny are said to be original and never been rebuilt. The truck has 276,000 miles on it now and I'm the third owner. The tranny makes a little noise at highway speeds (65 or so), but nothing abnormal.

[PanelDeland]

Mine did about 12-14 mpg.That was several years ago when gas was a bit cheaper.I liked the power and it would run 65 all day.Anything above about 65 was twisting it a little tight(by todays standards) since it had 3:73-1 gears.Taller tires would help a bit since you should have plenty of torque.

[71Longbed]

if i have an inline six and am swapping in a 350 will it just be a bolt on or do i have to move the mounts?

[71Chevy4-speed]

Don't mean to steal the question but my bud has a 69 with a 250 straight six and a 3 speed, its a C20 also.. do you guys think the RPM's would be to high with a small block in it? not sure the rear end ratio on it.. cause I've been wanting to find him a small block but hes afraid the tranny won't take it.

[71Chevy4-speed]

Longbed I think you can keep the mounts there but the motor just sits back farther.... don't qoute me but I thought I read this somewhere on this board.

[Brainchild]

Yeah you're right 71,it sits back a little further.I'm not sure the driveline will fit if you move the engine forward,I would think it would be too short.
Plus you get better weight transfer in the 6 cyl position

The tranny itself is a great unit.I have yet to tear one up,and I can tear up some stuff too.Tough little buggers they are.

[71Longbed]

so theres no need to move the mounts?

[Tx Firefighter]

no, the V8 will drop right onto the stock 6 cylinder frame mounts. The rubber motor mount pieces off of the 6 will even bolt onto the V8.

No moving or changing required if you don't want to.

[mrein3]

Originally Posted by 71Longbed

i was wondering how well this tranny works with a 350 and wut kind of mileage you guys get on it?

I have a 1970 cab on a 1971 4x4 chassis that I bought with a 3-speed manual. The tired 350 had a 2bbl carb on it when I bought it.
In that configuration I got:9.57 mpg over the course of 18,700 miles.
Since I changed the 3-speed out and put in a th350 I got: 8.77 mpg over 6000 miles.

When I put all the data together I have got 9.37 mpg over 24,700 miles.

All of the above miles were with the 2bbl carb and various cam shafts (I went 4 in that engine). My differentials have 3.73 gears. And most of the th350 miles were towing a 3000 pound boat.

I've said it before and I'll say it again, the best thing I ever did to my truck is swap out that 3-speed. The stupid thing never jammed - except at the worst time. Like waiting in line at a boat ramp. Or in traffic when I drove it to the Cities. My friend drove it from the boat ramp to my house one day while I drove my boat home. Usually the truck beats me to my house because of a no-wake zone. That day I got home and had the boat all the way up on the lift when I saw him pull in the driveway. He never did get it out of 1st gear.

Come to think about it that 3-speed was a pretty good theft deterrant. Nobody could drive the stupid thing but me. Now anybody can drive it.

[gr8scott51]

The 3 speed is fine, but if you do a lot of hiway driving, You'll wish for an overdrive of some type. My truck had a 305 with the 3 speed. Moving the shifter to the floor helped a lot. Ask Dubie, he just went through the I6 to SBC swap in his Mutt.

[Palf70Step]

The tranny itself is super durable. EdB has a 350 w/ speed in his. He's been through 4 engines and a couple zillion miles and the only thing that he has never touched is that 3-speed. And it gets worked. Unless you keep the linkages in top shape or go to floor shifter, shifting does become a pain. Linkages are the worse thing about the 3 speed.
I beleive the only thing you'll need is the clutch linage mounting on the engine is different from the 6 and V8. You may also need a different flywheel and clutch disc/pressure plate. Since your tranny position isn't changing, your driveshaft is OK. If you move it to the V8 Position, you might need to change driveshafts.

[CPNEJR]

I have a 350 w/3 speed and 3:08

not to steal the thread but does anyone know how this'll run at highway speeds and the gas milage

[dubie]

Yeah we did the inline 6 to small block swap in my 72 last winter. All you need to re work in the whole scheme of things is the Z bar for the clutch linkage, throttle linkage and you need straight down center dump ramhorns. The angled back ones run into the Z bar for the clutch linkage. We took the engine and tranny out in 1 piece, cracked em apart on the floor and bolted the rebuilt small block up to the 3 speed. You can install it right onto the inline 6 towers but it's a good idea to spend the $30 for new motor mount rubbers. And when install the driveshaft, we found it easier to disconnect it at the diff , slide the slip yoke into the tranny and then bolt it back up at the diff. If you plan on running an HEI, be warned that it is pretty tight back there, not a lot of room. It will go in and out with the cap off but there's no way in hell it's going in and out with it on unless you modify your firewall. If ya have any question, feel free to ask

[Palf70Step]

Originally Posted by CPNEJR

I have a 350 w/3 speed and 3:08

not to steal the thread but does anyone know how this'll run at highway speeds and the gas milage

EdB's 350 is a crate (3.08 rear) with a mild cam and he gets around 16-17 on the highway with it. And his will pull from an idle in third without a problem.
Course if your foot isn't educated yet you mileage will differ significantly .

[Brainchild]

Originally Posted by Palf70Step

EdB's 350 is a crate (3.08 rear) with a mild cam and he gets around 16-17 on the highway with it. And his will pull from an idle in third without a problem.
Course if your foot isn't educated yet you mileage will differ significantly .

That's my problem I have an uneducated foot
I thought my truck just liked the gas station