Transmission Options

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AuroraGirl

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What about just putting some boost into the 250?

Nothing crazy, just 7-8 pounds would make it peppy and totally different.
what you speak of is heresay

unless you mean supercharge, then, YES.
 

Catbox

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what you speak of is heresay

unless you mean supercharge, then, YES.

But a turbo is way easier to package on the unconventional straight six.
You can place it pretty much anywhere in the engine bay.
 

Bextreme04

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But a turbo is way easier to package on the unconventional straight six.
You can place it pretty much anywhere in the engine bay.

Damnit Catbox, I like the way you think.

Buddy of mine lives up in Seattle and has a 8.1L Vortec with twin china snails in his 73 Nova... it didn't cost him a whole lot and that thing is an absolute monster. Get a cheap ebay turbo manifold and a cheap china made turbo and you'll have all the power you will ever need. The problem will be in either converting the carb to be a blow through, converting to fuel injected, or making your own mount to put the carburetor before the turbo to pull through.
 

gotyourgoat

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what you speak of is heresay

unless you mean supercharge, then, YES.
So exactly why does one form of forced induction get a cheer while another gets a boooo from you?
 

DoubleDingo

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...........Edit: I had one of those 3 speed with overdrive that was in a 67 GMC I had. I gave to an uncle and he put it in his 72 and drove it for years. He loved that transmission.

I run one in Crusty Biscuit, the OD is a nice feature with 4.57 gears.

OP, makes sure what your rear end gear is before getting too far ahead of yourself. I'd also suggest keeping the stock setup, or the very least keeping the I-6 in case you sell it, you can have the original drive train as an optional switch back for the buyer.
 

AuroraGirl

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So exactly why does one form of forced induction get a cheer while another gets a boooo from you?
It's a joke, I think they are both truly valid. I'm being pretend fan girl about it. I personally like superchargers but turbos got their place like any thing else lol.

On inline 6, turbos actually excel well for reasons stated already and it helps their peppy part, where they usually suffer
 

DoubleDingo

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But a turbo is way easier to package on the unconventional straight six.
You can place it pretty much anywhere in the engine bay.

And with the right amount of minimal boost it creates a nice flat torque plane with endless HP.

1 and a half minutes of dyno...
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11:40 minutes of dyno
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DoubleDingo

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I agree the 250 and 3 speed have a certain amount of cool factor, but I really would like to cruise the thing somewhat efficiently. I would really like to keep the 3 speed. I wonder if I can hunt down one of those OD units for not too much scratch.

Search borg warner overdrive on craigslist, I have seen rebuilt ones for sale. But you need to have 4.57 gears with that transmission. Otherwise you'll do nothing but slip the clutch each time you take off from a stop. It's a steep 30% overdrive, so your 4.57 gears become 3.19. 4.10 - 2.87. 3.73 - 2.61. I guess you could run as high a gear as 3.73 and get away with it as long as you ran small diameter tires.
 

DoubleDingo

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This is what they look like...

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It's just a normal three speed with a different tailshaft housing, and a hole drilled in the back of the case for a rod to lockout reverse when OD is engaged. The tailshaft housing is basically a second transmission.
 

gotyourgoat

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It's a joke, I think they are both truly valid. I'm being pretend fan girl about it. I personally like superchargers but turbos got their place like any thing else lol.
If you have to explain it, it isn't a very good joke. :(
 

Catbox

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Ohhh don't get me wrong, I love a supercharger on an engine.
It would be my go to as I like the old school whine and just the visual it presents.

But for a straight engine, turbo for the win.
I have a 235 straight six in my '54 Bel Air.
If I were at all interested in keeping the 6 in there a turdblow would be the answer for making horsepower.
 

jorlain

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While a turbo is kind of attractive, I don't think I could make myself spend that much money to get 270HP.

I might be a little biased, though. Cars that should have V8s in them, but owners opted out of, irritate me, too.
 

DoubleDingo

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While a turbo is kind of attractive, I don't think I could make myself spend that much money to get 270HP.

I might be a little biased, though. Cars that should have V8s in them, but owners opted out of, irritate me, too.

I guarantee you would not notice that it's only 270hp because the power never lets up. The torque would pull like crazy keeping you pushing against the seat.

I say this as I have turbocharged Forester. Only 224 hp stock and the power is always there testing that clutch's clamping power. Fun as hell.

It's your truck, we just provide information and then sit back to see what you do.

Highway speed comes from torque and gearing, same as hauling. Fast times on the track come from horsepower and high rpms.
 

mcarlo86

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While a turbo is kind of attractive, I don't think I could make myself spend that much money to get 270HP.

I might be a little biased, though. Cars that should have V8s in them, but owners opted out of, irritate me, too.

Torque is the name of the game for pickups. That turbo'd 250 torque curve is flat, flat, flat. That would be an awesome setup. Now I want to find a 250..... :boxing:
 

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