Technical stupid SBC?

Yes, an add on OD bolted to the back of a th400 . depends on the motor home brand and age. Lots of motor homes were retrofitted with aftermarket OD units, there's a couple different brands, and then the "Gear vendors" OD/UD units were standard equipment in the 80s on some models.

 

Just two simple pices of advice from a guy who loves trucks! And school buses.

It's not the power you need to up, it's the torque and
final ratio you need play with!

We run this truck for ****'n'giggles, pleasure trips
and with 6 tons metric of dirt on the back.
And we do it with 300 cui inch, 100 hp, 5 speed(5 1:1), 5:45 (or is it 54) and 7.50 x 20 bias plies.
But it's a Diesel. I can do the legal 55 truck speed limit, can even do 60, but it's very loud at 60.




And empty around town it's as fast as a modern tractor without a trailer.
I get 9 km/l empty, and I get sound 4 km/l fully loaded!

You need to pay more attention on gears, then to the engine!

And this is no good answer to your question, but a thing to consider!!
See if you can sell the 350, rebuild or as parts, and go look for a diesel!
SBC are good, but like women, DD is what you go for!!

I don't know much about the TH400 slushbox, but I agree on the OD.
You can never get to many gears. Although 5x4 (double lever Mack b61 style) might be close. [emoji12]

Any reason you choose Auto? Because stick is much cooler, give you more gears, but if you don't like them, can't shift them or don't want to buy one, the auto should be good enough!

It's easier to give advice when we know all the facts.

Hope you get something out of my rambling, and it always puts you BTT regardless of the quality of my post!

 

Except that, I believe, is a Doug Nash over or underdrive (could be had either way). I have one sitting in storage.

 

700 r4 4l60e both have low 1st gear that would help with the low side.some where on here i ask a question about building torque with a sbc for towing. lot of good info.lots of different opinions also

 

Mr. King

I Remember that, the instant you mentioned it! I liked it too.

http://www.jalopyjournal.com/forum/threads/building-a-torque-motor.1002928/

 

beat me to it .thanks
http://www.jalopyjournal.com/forum/threads/building-a-torque-motor.1002928/page-7#post-11352738

 

That is a good and informative thread.

My case in point is, and always was "give me a leaver and I can move the world"!
You don't need more power, you need more gears!
1Hp pr Cui gives a good and sturdy mill.

You get more power in one single part by change rearend ratio, then any one single part in the engine!! Unless you change the as one unit!

 

Look around .I found a 93 Chevy dually here with 454 and a 480le overdrive auto for $1500 just last week. It gives you the big block torque and the overdrive that you want.
Several big block dualy pickup for sale on Craigslist for 2k or less.

 

I know this is a stupid question, but here goes;
Over here that's a Overdrive, cause it's OD and Direct. Over/under would require you could flip it front to back.
Sometimes we refer to a Over/under box, as 3 speed with under, direct and over.
I'm just curious.

 

Doug Nash (later US Gear)boxes could be purchased as direct/overdrive, or direct/underdrive.

I own a direct/underdrive one. It is not flipped, it is made the same way, case wise. The gears are different inside.

 

Now look up how much the computer to run a 4L80E is....

 

You buy the truck ,it comes with a computer. You basically install everything from the truck into the bus and you have a fuel injected engine, computer driven transmission . Not old school,but much more efficient. I am getting ready to adapt a 54 Merc body to a 2001 Lincoln town car ch***is with a 4.6 with all of the electronics.

 

I agree, and further more I don't get the whole computerized auto box?
Why do anybody want a complicated auto box with electronic stuff bolted to it?

To me that just screams limp gimp with a computer crush and no way other then google to tell the difference between spanner and ratchet.
No offend to limps, gimps or veterans with one leg!

Does it come true that I never been a auto-fan!!!!

I love the feel of a clutch and a stick, especially in trucks and Rods!

I understand the point of getting a full truck to gut out, but if I don't like the truck that's getting gutted to begin with!

And this is neither and insult to the OP or south cross!!
Just my wicked/whacked opinion!!

 

Look at Gear Vendors for an OD unit to go behind that T-400. They work great

 

The company gave it that name.
http://www.gearvendors.com/motorhome.html
I think it's a marketing gimmick ,,,
Bolting it on gives you overdrive
But if the unit is in OD and the Trans is in 2 that gives you a brand new gear that's under 1:1 3rd gear.

 

thanks for the advice
never knew they had bolt on ODs from the 'factory' on autos
gives me something else to look for when wandering through the junk yard
I went auto cause the wife suggested it, she likes the bus and I plan to keep it that way
I have an NV 4500 5 spd, but a good th400 and 350 came up and I couldn't p*** it up.
the main reason for the SBC and auto is the time frame that I have to finish this thing.
I have to have it running and driving by the end of April to drive it to a science fair that is showcasing work done by high school students.
future plans are for a something different for the engine but we can tackle that later.
I almost went 4l80 and I have set up computer transmissions with out issues in the past, but it is expensive
I like diesel but gas sounds better

was just wandering if I should put the $$ in the 882s or spend a little more and use the 462s
the only $$$ difference between the 2 would be for the hardened seats but some of that would equal out due to not having to buy pistons to up the compression for the 882s

don't worry about wasting time and $ on the 350 if not planning to keep it
I have other projects that it could find a home in

 

thanks

 

melling makes good oil pumps, they do not make good camshafts. Buy a cam shaft from a cam shaft manufacturer.

 

When I have a choice I go with the most Quench.

 

RV cam, 4. something gears, internal or external OD would be a nice addition, run it. There's only been a few million of these 350s set up for similar tasks right outa the factory. Keep the RPMs reasonable and it should last several graduating cl***es....

He's not trying to run .2 under the national record ******, Melling's known for decent service parts. You have one fail, or spec issue, or...?

 

The 3.875" crank was made for the 410" sprinters which now use it or a 3.800". Of course they are super light but **** makes a standard one too. Used with a 400 block or a Dart and you've got a 420" without messing with the block or cam especially good if you order it with 2" rod bearing. For me a 420" with off the shelf parts is a godsend for our dirt race car.
For what you want to do, a set of 194 heads will give all all the torque at the lower rpm you need with the 350 block and 396" with a .030" over bore. It's good to read parts availability on the Internet. JD

 

Uh you want to part ways with the nv4500???

 

maybe
I have traded for a 64 c50 I thought about using it in, would make a nice car hauler
its the shorter input chevy version with the lower 1st gear 93-94 ish
no bellhousing, that's one reason I used the th400

 

Some once great gear bangers develop physical limitations, it's life I guess. In your wicked and whacked opinion are they allowed to keep their love for hot rods and trucks and retain what pleasure they can even if it means suffering with an automatic?

So you might understand - I don't think anyone wants a computer controlled Trans, I mean they don't wake up and say "hey I'm going to add complication into my life" , right? So a bit of limited focus Trans history to keep the progression straight. There were th350 and Th400 Trans. The 350 got OD and then went to the 700R4 trans. The th400 didn't get OD added. The 700r4 was the everything Trans and changed names to 4l60. After a while they went electronic and that became the 4l60E , follow? Still no version of the Heavier duty TH 400 with OD until the 4L80E. That's the only way you can get it, dependent on a computer controller. If you need a HD Trans and want OD then you're forced to take the computer too.

 

I have no objection to someone needing a slush box, I just ask the question of why people who don't need it, wants it!
If I came out disrespectful, I'm sorry, I was going for cheeky/young in cheek.

I wanted to recommend to going for a designated truck transmission and fiddle with rear ended gears to get the low end grunt of a truck and the top speed of a pickup or van.

I still think that a if you drive your car like you are 18 all over again, you will never be happy with anything other then a good V8 gas job. And auto will do just fine.

But if you drive sensible, wants to tow a long way and want stump pulling torque at low money I would still recommend a 6.5 diesel V8 (can be had with truck trans or auto and OD) or a ***mins 12v.

But I understand his reason to go with Gas and auto, I just wanted to make sure he didn't steered around Diesel because they are no good!
But high displacement, low spinning low stress SBC will do just fine with a mild RV cam.

 

I would use the 882s over the 462s because of the hardened seats. On this set up you have a good possibility of valve recession over time without

 

Guess I'm confused, you are building a bus, you want HP, you don't want to spend any money and you are worried about gas mileage and want performance too. Take the suggestion about BBC or big cubic inch anything because cubic inches = torque. Any stock big inch junkyard motor makes big low end torque, will serve you well and figure your gearing w/ tire dia you are going to use, your highway cruise speed, figuring around 2000 rpm. A heavy bus needs torque, not a high winding SBC. IMO, your wish list is in the unobtainable bracket, but you are building something unique which is cool and wish you good luck w/ your project. Have at it !

 

Its been a while but back in around the turn of the century replaced lots of Melling cams. At least here locally. Some of them came to me with a new replacement Melling cam which also failed and others were replaced with good subs***utes from major cam manufacturers.

Actually the year that I joined the HAMB ('03) we pulled the 235 in the Raven's truck at least 5 times, engine built, run in by a local 235 guru and running the proper oil as specified . Flatten the cam out comes the mill back to the machine shop, Melling was his go to cam shaft. One night in desperation we pulled a junkyard motor out from under his bench and installed it, in place of the fresh new motor.

I run melling pumps as did my father before me, good pumps. Nothing against Melling, just that I don't care for their other parts.

 

I also would run the 882s for the hard seats. You'll be running at full throttle a good part of the time with the small motor/heavy bus and that's hard on valve seats.
An alternative to look at:
My son has an '04 GMC 1 ton with the tall deck 496 big block/allison auto trans. We load it up with enough stuff to keep us fed and clothed for a week, spare wheels and tires, gas, tools and hook up his trailer with ZO-6 'vette on it.
It gets a shade over 10 MPG loaded but you'd never know there's any weight in it! This thing's an animal! All the power you'd ever need and fair MPG. And it's smooth as silk...Just a thought.

 

Years ago I owned an old full sized school bus that had a 283 "taskmaster" sbc in it and a 4 speed granny low trans.We cut the back of the body off and used it to haul a dirt track car on.Point is it would cruise at 50 mph loaded with no strain.Surely a 350 can manage to move a lot less weight at respectable speeds? Put your 350 in it,if you dont like it you can always change it later.