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Discussion Starter · #1 ·
Hi all,
First, thanks for this site. I'm just starting to get to the engine/trans part of my build and will certainly be asking a bunch of questions. I have a 4BT from a Ford Wonder Bread truck.

The main questions I'm looking to answer are:
1. Which 2WD automatic trans to run? I see comments that the 700R4 is a poor choice then I see it isn't... :confused:
The only thing I'd ever tow - if I tow at all - is a couple motorcycles. Figure less than 2000 lbs total, including the trailer.

2. What RPM should I be targeting for freeway cruise? I'd like to maximize mpg but not at the complete expense of some level of 'getting out of its own way'.

3. Is there a 'standard' set of mods that I should be looking at? Near as I can tell, I do an HY35 9cm, 3K spring kit and tweak the fuel screw a bit. I want some improved performance while retaining reliability.

4. Any recommendations for suppliers of the 'factory' power steering pump assy and an A/C condenser mounting bracket?

5. Anyone converted to WVO? Can you share learnings, do's and don'ts?

Also, I'm posting the build thread for the rest of the project here. Take a look if you're interested in seeing how Carbon Fiber can be incorporated into a 55 year old, diesel powered hotrod Suburban!
http://67-72chevytrucks.com/vboard/showthread.php?t=249457

I appreciate any guidance y'all can provide. Thanks and drive safely,
Chris
 

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Nice work!

I looked at the progress you have made and I'm ery impressed with the sheetmetal work. I also like your ideal of using carbon fiber for some trim work. I do a little of composite work myself.

To answer a few of your questions:

You should have no problem with a 700R4 Some people are critical of them but I have one behind a 4BT in a 93' Suburban. Not quite done but just about there.

You best bet besides building a strong a 700R4 is to have a good torque converter. Get a custom one made that will bolt to the 4BT's flex plate. I had one built using a carbon fiber lock-up clutch which will cut down on heat build up when going into lock up because that was the 700's worst nightmare is heat.

If you go with a 700 then go and cut off a throttle bracket from a 87-93 GM throttle body injection that has a 700R4. That throttle bracket has all the proper dimensions for the detent cable geometry so when installed your detent cable will be already adjusted. I took the cut off throttle bracket and drilled mounting holes to bolt to the existing throttle lever on the 4BT's injection pump. Or you can copy and fabicate your own. That is the number one issue when going with a 700R4 is the detent cable adjustment. The 4l60E would be a good choice because even though they share the same internals however, the valvebody is eletronically controlledwhich makes the fluid pressure better mananged. Just need a stand alone computer.

Operating range for cruising for these engines from what I read so far is best at 1500-1700 RPMs. that's when these engines peak at their fuel consumptions efficientcy according to engine spec sheets. My gearing will be 3.42 gears with 29 inch tall tires, which will be at 1860 rpms at 70 MPH. I would like to get it lower but 3.42's is a low as I can go with GM IFS in my rig. I can may go with taller tires.

For AC brackets I use the high mount AC bracket part number 3930888 from the Cummins dealer. I don't have the romm between the frame like solid axle trucks do which is why I went with that bracket. If you have the room between your frame you can run stock dodge factory AC and alternator off of the 5.9 with a dodge AC compressor.

There are plenty of options to choose from with a wealth of experience on this forum so you came to the right place.

Keep the pics coming!
 

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Petaluma, Ca

Tygaboy,
I'd love to see how drop in a 4bt, as I'm looking for one for my '87 K10. If you would like some help, I live near Petaluma and am more than willing. And if yours goes well I can justify the cost to my wife!
 

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Discussion Starter · #4 ·
If you go with a 700 then go and cut off a throttle bracket from a 87-93 GM throttle body injection that has a 700R4. That throttle bracket has all the proper dimensions for the detent cable geometry so when installed your detent cable will be already adjusted.
Operating range for cruising for these engines from what I read so far is best at 1500-1700 RPMs. that's when these engines peak at their fuel consumptions efficientcy according to engine spec sheets. My gearing will be 3.42 gears with 29 inch tall tires, which will be at 1860 rpms at 70 MPH. I would like to get it lower but 3.42's is a low as I can go with GM IFS in my rig. I can may go with taller tires.

For AC brackets I use the high mount AC bracket part number 3930888 from the Cummins dealer. I don't have the romm between the frame like solid axle trucks do which is why I went with that bracket. If you have the room between your frame you can run stock dodge factory AC and alternator off of the 5.9 with a dodge AC compressor.

There are plenty of options to choose from with a wealth of experience on this forum so you came to the right place.

Keep the pics coming!
Thanks for the info. I'm going to be running C4 'Vette suspension so I'm limited to 2.59, 2.72 or 3.07 rear end ratios. Need to determine the tire size I want and take it from there.
I'll be in touch. Best of luck with your project and let me know how things progress.
 

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Ok I am not one to use punk teenager words like this but this deserves it. That is the sickest truck I have ever seen. You do some amazing work with that composite fiber. Who knows you may have some business comeing your way in the future. True inspiration for us doing older 50's swaps.
 

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That looks like a VERY VERY kewl vehicle dude!

I think back to my younger (stupider!) days when we took the engine out of a pretty decent '65 Suburban and junked it!

I live vicariously through youse guys!
 
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