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Discussion Starter #1
I am new to forums and swaps in general so I apologize if this has already been asked and for my lack of knowledge. Anyway I have a 4bt that I want to swap into a 1965 ford f100 2wd with the 300 inline six. I plan a putting a t18 trans behind it with a ranger torque splitter that would give me 8 forward gears and an over drive.I am primarily building this for economy so I dont plan on tuning it up to much or using it as a rock crawler. I have a few questions I would like some help with though.

1. How I should go about motor mounts and mounting brackets?

2. Can I use the stock suspension system or will I need to beef it up a little?

3. Is there any parts, hints, or things I haven't thought about that would be useful?

Any and all help would be greatly appreciated!
 

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cut...

1. How I should go about motor mounts and mounting brackets?

2. Can I use the stock suspension system or will I need to beef it up a little?

3. Is there any parts, hints, or things I haven't thought about that would be useful?

Any and all help would be greatly appreciated!
1. FAQ: show off your motor mounts.

2. The 300 6 weights about 500 lbs, the 4BT about 750 lbs or the same as a big block chevy. Should be OK with stock but might sag due to the age of the springs.

3. Unless you like to shift 8 gears, I would use a NV4500 or the ZF that came behind the 300 6. A close ratio trans is preferable for use with the 4BT due to the some what limited rpm range of most Diesels. Gearing is most important for a Diesel to maximize performance. You want to run the rpm near max torque for economy at your cruise speed, about 1700 rpm for the 4BT. That also depends on your power to weight ratio.
 

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Here's a white paper authored by Cummins on getting the most fuel mileage out of your Diesel. Even though it's aimed at class 8 tractors and trucking company the principals still apply.
 

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I had an '83 Bronco that originally had a 300 and a 4speed I installed a 4bt with conversion mounts that allowed me to use the 300 frame side mounts and an adapter that allowed me to bolt up a small block zf5speed, it was the wide ratio but in the Bronco it worked well.
I also used the stock suspension and had no problems with it.
If you need the transmission adapter PM me I have a Line on one.
 

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Discussion Starter #5
Thank you guys for the help. I know it would be more practical and cheaper to just drop an NV4500 but I think im going to stick with the torque splitter because I think it would be a kick in the pants to have two shifters and 8 gears. I calculated the ratio for each gear and I believe that it will work for me. I am unsure of the gearing in my rear end but Im guessing I have 4.10 gears which would give me a cruising speed of 55mph just over 1700 rpms which is ideal. When I get farther along in the project and more money I may swap in higher gears to get me to 65-70 mph which is all the faster I need to go. Let me know what you guys think and thanks again!
 

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I have a 1963 Chevy with a ranger overdrive in front of the original sm420 4speed and have had the 4bt in it for almost 18 years now so I know a little about driving with one. They work great but have some draw backs. When you first get one you will have a learning curve in driving it because it makes the synchros in the main transmission work harder, so they better be in good shape, and you have to match the speeds closer at down shifts than you do on just a 4speed alone.
They are a little noisy in high range and you will find that with 4.10 gears all you will use it for is overdrive when the newness of it wears off.
 

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Welcome to the forum. No real issues doing the transmission setup other than what's been mentioned. Sort of wonder why you're using the T18 instead of the newer T19 which came behind the 4bt in E350 vans. Is 55 MPH as fast as you plan to drive? Most guys want a rear gear in the lower 3's so they can cruise at interstate speed at 1800 RPM. You could do 55 in 4th gear and switch to OD for interstate speed that way. If you happen to have a Ford 9" rear, you can get darn near any gear you can think of for those.
 

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Discussion Starter #8
Welcome to the forum. No real issues doing the transmission setup other than what's been mentioned. Sort of wonder why you're using the T18 instead of the newer T19 which came behind the 4bt in E350 vans. Is 55 MPH as fast as you plan to drive? Most guys want a rear gear in the lower 3's so they can cruise at interstate speed at 1800 RPM. You could do 55 in 4th gear and switch to OD for interstate speed that way. If you happen to have a Ford 9" rear, you can get darn near any gear you can think of for those.
From what I have heard and please correct me i'm wrong, the t18 would work better due to the wider gear ratios. I also have a t19 that was behind a 4bt but it has the close ratio and if i split the gears with the ranger overdrive it would almost be the same ratio as just up shifting if that makes and sense. I know there are wide gear t19s but ive heard they were not as common and harder to find. As for the rear end upon further investigation I've found out I actually 3.70 gears instead. This would let me cruise about 65 mph at about 1900 rpm which is close to the ideal range. I am surrounded by mountains so the highest posted speed limit around is only 65mph and I do not not plan on doing much interstate driving. In the future I may drop the rear gear lower if need be but for now it will suffice. Thanks again everyone for the help and I plan on posting some pics in December when I get some time to work on my project as I am in college right now.
 

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If you check the ZFS or the M5R2 transmission ratios you will find one that is very close in numeric ratios to the T19 except the T19 is not an overdrive. I purposely save one of these T19's with the intent of possible adding an input side over drive unit to it. The down side is that by the time you check the T19 for any replacement parts to make it like new again and then factor the cost of the input side add on over drive unit it ends up about the same as getting a nice like new condition M5OD or a used ZFS series transmission. You sort of end up with the same thing in the end but with fewer parts to wear out. You will get over the infatuation of the two shifters and splitting gears after you drive the truck around for awhile. As previously mentioned you will end up starting out in "direct" first gear and going to fourth then shifting into overdrive with the T18 or T19. Like any new toy it gets old and you will be wondering why it seemed like such a good idea especially if things start to break in the OD unit or in the transmission. Diesel engine power bands usually tell the drivers that they do not like wide ratio transmissions.
 

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Both the T18 and T19 had various gear ratios. The transmissions came in Fords, Jeeps, and IH's. The Ford T18 had gear ratios of 6.32, 3.09, 1.69, 1.00, & R7.44. Jeep was the same as Ford except for 1972-1975 which was close ratios of 4.02, 2.41, 1.41, 1.00, & R4.73. IH had both the styles like the Jeeps. On the T19, Ford and IH offered 3 ratios. The common ratio for most road vehicles was the 4.02, 2.41, 1.41, 1.00, & R4.42 close ratio. The wide ratio model was 6.32, 3.09, 1.69, 1.00, & R6.96. That one only came in HD applications like F500 and above. Ford had another used for a few years that had ratios of 5.11, 3.03, 1.79, 1.00, & R5.63. With your splitter, it's possible a wide ratio may work the best. If you just wanted to use that unit for the OD only, then the close ratio would be better. Odds are you'll seldom ever use 1st gear low. I had a '73 F100 4x4 that was geared 3.73 which I suspect what yours is. With its NP435 transmission I seldom used 1st gear unless I wanted to crawl.
 
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