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Discussion Starter · #1 ·
Was wondering if anyone here has done this swap into a 67 to 72 chevy truck? I have a 72 1 ton extendid cab dually and am thinking about going this route. I now have 4.10 gears and am running Cooper C-140 8r-19.5 tires that measure 34" tall... is this a good ratio for this combination? I also have a divorced 2 speed auxillary transmission so I could go with either the 465 4 speed or the Th-475. Last question for now, is anyone making a motor mount kit that would simplify fabbing one up?
 

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Was wondering if anyone here has done this swap into a 67 to 72 chevy truck? I have a 72 1 ton extendid cab dually and am thinking about going this route. I now have 4.10 gears and am running Cooper C-140 8r-19.5 tires that measure 34" tall... is this a good ratio for this combination? I also have a divorced 2 speed auxillary transmission so I could go with either the 465 4 speed or the Th-475. Last question for now, is anyone making a motor mount kit that would simplify fabbing one up?
There's a thread on here for a 72 pickup converison, check out the buildup threads section.
 

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Was wondering if anyone here has done this swap into a 67 to 72 chevy truck? I have a 72 1 ton extendid cab dually and am thinking about going this route. I now have 4.10 gears and am running Cooper C-140 8r-19.5 tires that measure 34" tall... is this a good ratio for this combination? I also have a divorced 2 speed auxillary transmission so I could go with either the 465 4 speed or the Th-475. Last question for now, is anyone making a motor mount kit that would simplify fabbing one up?
Take a look in the Vendor section ,I will be starting them shortly .

Scott
 

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Use the Search, Luke!

I now have 4.10 gears and am running Cooper C-140 8r-19.5 tires that measure 34" tall... is this a good ratio for this combination? I also have a divorced 2 speed auxillary transmission so I could go with either the 465 4 speed or the Th-475. Last question for now, is anyone making a motor mount kit that would simplify fabbing one up?
The tire size and final drive ratio you have is very common in the P30's from what I've read (and just happens to be what I've got in mine..). That gives you 55-57 MPH wide open stock with no overdrive. If you've got a 3200RPM spring or have adjusted max idle to allow 3200RPM, you get about 75MPH. But you REALLY want that overdrive, or go with a faster rear end if your top gear is 1:1.
 

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Was wondering if anyone here has done this swap into a 67 to 72 chevy truck? I have a 72 1 ton extendid cab dually and am thinking about going this route. I now have 4.10 gears and am running Cooper C-140 8r-19.5 tires that measure 34" tall... is this a good ratio for this combination? I also have a divorced 2 speed auxillary transmission so I could go with either the 465 4 speed or the Th-475. Last question for now, is anyone making a motor mount kit that would simplify fabbing one up?
I put a 4bt in my 71 chevy 4x4. It is mated to a 700r4. You can see my buildup with pics in the buildup forum. I removed the crossmember and welded my own mounts. The mounts weren't that difficult to make. Mine are strong and ugly. If you want them strong and pretty well that takes alot of time and effort. The exhaust exiting the turbo must turn down 90 degrees before the firewall. It is tight. My tranny is about 2.75" longer than a turbo 350 which have me some extra room. I also beat the firewall in with a hammer and cut all the straight pipe off the downpipe. It turns down imediately after the turbo. I could have made it turn sharper, but this will hurt your flow. You can also have the motor lower which gives you some extra room, but too low and you have trouble with the front diff hitting the oil pan if the suspension bottoms. INsulation-67-72's are all steel. It's noisy without alot of insulation. Vibration noise can also be a issue. I have 3.73's with 31" radials and I get 22mpg. I drive my truck around now daily and I don't have that constant sinking feeling because my gas guage is falling so fast. Sometimes it was nice to be sucked back into the seat by the 400 that was in it, but I don't miss it. The only downer is noise and vibration. I think the 6bt would fix some of this, but then your back down in the high teens for mileage.
 

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Discussion Starter · #6 ·
I put a 4bt in my 71 chevy 4x4. It is mated to a 700r4. You can see my buildup with pics in the buildup forum. I removed the crossmember and welded my own mounts. The mounts weren't that difficult to make. Mine are strong and ugly. If you want them strong and pretty well that takes alot of time and effort. The exhaust exiting the turbo must turn down 90 degrees before the firewall. It is tight. My tranny is about 2.75" longer than a turbo 350 which have me some extra room. I also beat the firewall in with a hammer and cut all the straight pipe off the downpipe. It turns down imediately after the turbo. I could have made it turn sharper, but this will hurt your flow. You can also have the motor lower which gives you some extra room, but too low and you have trouble with the front diff hitting the oil pan if the suspension bottoms. INsulation-67-72's are all steel. It's noisy without alot of insulation. Vibration noise can also be a issue. I have 3.73's with 31" radials and I get 22mpg. I drive my truck around now daily and I don't have that constant sinking feeling because my gas guage is falling so fast. Sometimes it was nice to be sucked back into the seat by the 400 that was in it, but I don't miss it. The only downer is noise and vibration. I think the 6bt would fix some of this, but then your back down in the high teens for mileage.
Thanks Rob, I read your build up post earlier today and found it very informative. The noise issue was something I had not even thought about, I had heard of vibration being a problem in some swaps. I have heard of "fluid mounts" is this what came stock on the P-30 vans? And did you do any reinforcing of the frame on your truck?
 

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I didn't reinforce the frame. 67-72's also came with inline 6cyl's. The inline 6 weighs within 75lb of the 4bt. My mounts are made of 3/8" X2.5" bar stock. I have 1.75"X.25" bar stock diagonal reinforcments. It is welded thick, ugly and strong. If you intend to do high speed off roading. rock crawling or other activities such as this the frame might need to be reinforced. I did my welding with a battery powered ready-welder spool gun. My steel cutting was done with a abrasive blade I put on my chopsaw and my sawzall with a lot of "free sample" lennox bi-metal blades. Yes you can cut 3/8" steel with a sawzall(earplugs, oil, box of new blades, and patience). The rubber bread truck mounts are supposedly fluid mounts. Remember they will compress about 30-50% when the weight of the motor is on them. You can move the engine up and down about 6" between the oil pan hitting the front diff and the tranny hitting the tunnel. The bottom of my rubber motor mount sits on a 3/8" plate which is 1/2" lower than the bottom of the frame rail. My most time consuming issue beleive it or not was trying to peice together water hoses and pipe for the radiator. I had the intake and airfilter from the bread truck. I had the complete exhaust from the bread truck. I bought a 8ft peice of 3" flex pipe to complete the exhaust. Exhaust turns out right in front of the right rear tire. My fuel return line T's back into the regular fuel line back near the tank. Before you bolt the motor in bash the firewall in a bit with a big hammer to help clear the downpipe. You can probably get the rest of the clearance by cutting the straightpipe between the turbo and the elbow. If you still can't get enough room you can cut and reweld it sharper than 90 to make the turn quicker but this will hinder flow.
 

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Discussion Starter · #9 ·
72 1 ton (extendid) cab dually ?? did you do that your self ? lets see some pictures!
I wish I could take credit for the body work but it was done by a shop in Manhatten Kansas, I did the chassis and all the drivetrain.



 

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"Slick truck man, I had a 72 and a 70 we restored a few years ago. That thing is begging for a 6BT, go large man! (4BT would be cute, but wouldn't do the truck justice IMO )"

I agree, was thinking the same thing when I saw the pictures.

Nice truck.
 
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