Motor Home 440 swap

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Jim Wyatt

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I have an original 1971 motor home 440 and 727 transmission with 36,000 miles on it. I'm giving some thought to installing it in a Barracuda. However, I,m wondering if the cam should be changed due to the difference in application (from a 24 foot motor home to a Barracuda) I realize there may be a difference in the front sump or rear sump oil pan (I don't recall which but, think I have both to work with). The exhaust manifold and motor/mounts will be another issue. The area I need the most help in... is setting the motor up for a pump gas muscle car (nothing radical, mild performance & street driven). Another concern is MPG. The thermoquad was working fine when I parked the motor home. Will MPG improve with an aluminum intake and different carburetor? What MPG can be expected from a 440 Barracuda under normal driving conditions with 8 3/4 & 2.76 gears? (If I can't afford to drive the car 70 miles to a car show I'll stay with the 318) I assume the same transmission and torque converter will work. (provided the drive shaft is altered)

Thanks,
:read2: Jim Wyatt
 
Another thing to look at is the lack of a slip yoke on the motorhome 727 I believe it also has a short tail housing.
 
Yup, tail shaft on the the trans will be different. Has a short tail shaft with drum style parking brake. Easy to change that over though. Need a new output shaft and long tail house.
 
Jim Wyatt said:
I have an original 1971 motor home 440 and 727 transmission with 36,000 miles on it. I'm giving some thought to installing it in a Barracuda. However, I,m wondering if the cam should be changed due to the difference in application (from a 24 foot motor home to a Barracuda) I realize there may be a difference in the front sump or rear sump oil pan (I don't recall which but, think I have both to work with). The exhaust manifold and motor/mounts will be another issue. The area I need the most help in... is setting the motor up for a pump gas muscle car (nothing radical, mild performance & street driven). Another concern is MPG. The thermoquad was working fine when I parked the motor home. Will MPG improve with an aluminum intake and different carburetor? What MPG can be expected from a 440 Barracuda under normal driving conditions with 8 3/4 & 2.76 gears? (If I can't afford to drive the car 70 miles to a car show I'll stay with the 318) I assume the same transmission and torque converter will work. (provided the drive shaft is altered)

Thanks,
:read2: Jim Wyatt
Click to expand...
The cam will be a RV cam....torque for hauling all of the weight of the motor home...torque convertor will be the same way for the same reason...my opinion would be to trash both of them...you will need a center hump oil pan...you won't be able to reuse the exhaust manifold or motor mount....try looking at Shumacher Creative Services for their mounts and their Tri-Y headers...the thermoquad is a great carb and if it was working before use it again...aluminum intake and other carb is for performance reasons not better mileage...if you were using pump gas before it will be fine as long as you don't do something to change the combustion ratio...try 8 3/4 with 355 gears..trans will be fine with longer output shaft and tailshaft.....


take a look at my build and it may help you somewhat.....

http://www.forabodiesonly.com/mopar/showthread.php?t=96239
 
Thanks,

I was not aware of the transmission tailshaft issue. Can the tailshaft & housing be replaced by removing the tailshaft housing or do you need to disassemble the transmission? Any recommendations on the torque convertor or cam. I'll probably go back with standard equiptment unless there is a good chance I'll regret it later. Still concerned about the MPG, are we talking 8 to 9 MPG with the change in gear ratio or can we move up around the 17 to 20 MPG...

TO: 67Dart440GT ~ No trans. style Drum parking Brake on this one.
TO: 340Mopar ~ Sorry, I failed to mention the engine block indicates '71' 440.

Jim Wyatt
 
I installed a rebuilt 440 in a 69 Charger and later that year drove it to the Nationals in Columbus from here in VA. Gas mileage to the show, back and forth to the motel, a couple of passes down the track and back home netted 19 mpg! That was using 2.76 gears. My buddy drove my 318 Challenger and it got 18 mpg (with no track time). Can't remember what the mileage was around town - think around 13 or 14. The Charger was a daily driver.

Sent from my i-phone
 
Jim Wyatt said:
Thanks,

I was not aware of the transmission tailshaft issue. Can the tailshaft & housing be replaced by removing the tailshaft housing or do you need to disassemble the transmission? Any recommendations on the torque convertor or cam. I'll probably go back with standard equiptment unless there is a good chance I'll regret it later. Still concerned about the MPG, are we talking 8 to 9 MPG with the change in gear ratio or can we move up around the 17 to 20 MPG...

TO: 67Dart440GT ~ No trans. style Drum parking Brake on this one.
TO: 340Mopar ~ Sorry, I failed to mention the engine block indicates '71' 440.

Jim Wyatt
Click to expand...

That's good news... otherwise you would of had to disassemble the trans.
 
Yes you can change the tailshaft out by removing the snap ring that holds the entire tailstock on. You need good pliers,dont try it with the el cheapo set. As for mpg,my buddy slapped a 440 in his 68 Barracuda and got near 17-18 on the highway. You can fool the motor by keeping the vacuum signal to the motor high. This requires a small carb. He had a 550 or 600 cfm carb on there at the time but it was waaay down on power as a result. I think the tq and a good multispark ignition will help. 3:23 gears at the lowest. Believe it or not dont put big fat tires on either. The skinnier tire will produce less friction and better mileage.
 
I am in the process of installing a 440/727 from a motorhome into a 66 Fury. I planned on swapping everything out to the motorhome tranny, but I actually scored a good BB 727 from JMac'sMopars today for free. :cheers: Thanks Jeremy that's too cool. I would suggest doing this, because there is just too much to swap over. Speedo gear, shifter linkage etc.

I have ordered the motor mount conversion and had the center sump oil pan, so I will be installing it next week.
 
One thing that might help you out futher of the gas mileage is to run a Performer intake....a .480 lift cam and a 600 cfm carb....this would put it close to stock...the Performer intake is just a little better than stock and weights alot less
 
Thanks Again,

I appreciate the actual driving experience 'example'. I realize all things are not equal but, it helps ease my MPG concerns. I enjoy driving the car and did not want to regret a big block swap... I'm afraid 8 to 9 MPG would have been a regret. I'll be selective with the cam and, as was mentioned, 'stay close to stock grind'. I'd also thought about the Aluminum Peformer Intake (less heat retention and the fuel should atomize better) - aluminum intake & waterpump (less weight). Maybe a little performance gain also. In addition, I do have the multi-spark ignition.

After reading all the replys... The swap will be a little more involved than I thought. Therefore, I'll probably make this a winter project. Otherwise, i'll be garaged for the summer.

Jim Wyatt
 
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