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Discussion Starter · #1 ·
Ok, I've been trying to decide the best way to get a powerful diesel engine into my 1995 SC SB F-150 for about a year now. My main goals are to replace the gutless and worn out 5.0 with a diesel to get better mpg and I want to out run my buddy's Dodge Hemi Ram.
I like the potential of the 6bt, but I think it'd put more strain on the frame and suspension then I'd be comfortable with. And honestly, it'd be way more then I'd ever need.
Now I'm thinking that the 4bt might be the way to go, but I could use some feedback and advice, especially from anyone that's done a Ford swap. I know the 4bt is basically a 6bt w/ 2 cylinders missing, but do the motors have the same tranny bolt patterns? Is it possible to bolt my current 5 spd to the 4bt? What seems to be the limit for reliable and streetable power? Do the 4bt's have the same fuel pumps as the 6bt's? Also, anyone with advice, tips, ideas, or whatever, I'd greatly appreciate it. Thanks!!
 

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I'm putting a 4BT into a 1990 F150 SC 4X4. I'm assuming you have the Mazda M5OD 5 spd, it will bolt up to the Cummins Ford flywheel housing but I'd recommend you go with the ZF S5-42 from a F250/350 with a 5.8 gas, its much better trans for a 4B. Both the 6B and 4B with the VE injection pumps use the same diaphram type fuel pumps. Lots of threads about all this on here.
 

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I would say run the Mazda tranny until you break it, I know a handfull of people who beat the crap out of that tranny with no issues. I think the Mazda tranny would be spaced quite well... As for beating your buddies Hemi Good Luck unless you turn it up a bit, a buddy of mine with a Hemi 1500 blew by me like I was standing still, At stock power I raced my ol man in his 97 F-250LD w/ a 5.4 and he had me by a truck length at 1320ft, and his truck has 1000lbs on mine

My build Thread http://www.4btswaps.com/forum/showthread.php?t=242
 

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do the motors have the same tranny bolt patterns? Is it possible to bolt my current 5 spd to the 4bt? What seems to be the limit for reliable and streetable power? Do the 4bt's have the same fuel pumps as the 6bt's? Also, anyone with advice, tips, ideas, or whatever, I'd greatly appreciate it. Thanks!!
Yes the 4bts and the 6bts have the same bolt pattern so if it bolts to a 6bt it will fit a 4bt. the limit for reliable power, I am sure everyone will have a different opinion IMO 200hp and 400+ ft/lbs would probably be the upper limit and have it live a long time. they do have the same pumps, most come with a royary pump similar to the first gen dodges also 2 inline pumps the P pump is similar to a P7100 pump on 2nd gen dodges and also an inline A pump. make sure you get a an automotive pump rather than one from a stationary pump or genset with a fixed rpm setting. Are you wanting Auto or Manual? 2x4 or 4x4?

Gaza
 

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Discussion Starter · #7 ·
Right now the plan is to stick with the stock 5 spd to make the initial swap cheaper, if possible. The truck is a 4x4.
After going thru most of the posts I'm confused about something and I hope you guys can explain it to me. Alot of guys talk about the chevy and ford bell housings, so I'm assuming that depending on the application, some 4bts came with bell housings to mate with a ford or chevy tranny. If anyone can explain the details to me, I'd really appreciate it.
Also, I've never seen a 4bt in a truck, so I'm wondering how you guys re-mounted your accessories (power steering pump, alt, etc) and where you got your motor mounts from?
 

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if the 4b could be made to RELIABLY out -power a 6b, then ther would be WAY more swaps.
Lee,
What has been your experience with shortened engine life on 4BT's that have been tweaked out for more power than stock? You are always mentioning this, and I wonder what kind of failures you have seen.
Thanks,
Mikel
 

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none, ZERO. theres quite a few threads on TDR and similar forums where 400hp from a 12 valve rotary pump 6bt is on the HIGH side of reliability. if we use the 2/3 theory then that puts you at 265. the marine techs have complained on the marine boards arout the cummins speced 250hp.

as many 6b tweakers out there, i would think they would be much more interest in a 4bt. this is all my thoery. like i said. run 250hp and lets see. i dont have that kind of money to tweak that much hp, on a gamble.

i would love to see it. until i do i just dont think its possible
 

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Lee,
IMO the marine 4BTs are not good examples. Boat engines tend to run at much higher sustained power levels than automotive engines. And I wonder how many of those with failed marine 4BT's weren't monitoring the EGT's.

I don't think it can be argued that engine durability and output are inversely proportional, probably in an exponential relationship. Stock 4BT's can reach ridiculous mileage if minimally maintained, often reaching the million mile mark. My goal is 200HP reliably with my CPL 858 - If this decreases my engine's life expectancy to 300,000 miles, I don't think this is a bad trade off. I really don't know what the performance/wear curve looks like.
Thanks,

Mikel
 

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well 200hp would be equivelent of a 300hp 6bt, first gen. (i dont buy the 2/3 theory, but for arguement s sake)

then where are all the 300hp 1st gen rotary pumped 6bt's? and for that matter what did it cost to get them there? why not run a 200hp 6bt? thats much easier, and cheaper?
 

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click the pers link. of 9 trucks (one has a p-pump) there are 5 below 250, so 50% of the tweakers at this event were unable to duplicate where you want to be.


Jeremy T. 680 ( water / meth ) [2/3= 448]
Mark W. 602.6 ( P-Pump, #2 only ) [2/3= 397]
Chris R. 401.2 ( water / meth ) [2/3= 264]
Bob B. 361.9 [2/3= 238]
Stan T. 325.6 [2/3= 214]
Dave M. 307.6 [2/3= 202]
Roy C. 254.3 [2/3= 167]
Al 246.6 [2/3= 162]
Cole D. 222.2 [2/3= 146]
TJ 217.1 [2/3= 143]
Nick 213.0 [2/3= 140]

so it looks like if the 2/3 applies, then a more reasonable expectation seems to be 140~170????

where am i getting confused????
 

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Perhaps I should have specified - 200HP to the crank. That would translate to about 150 to the wheels. Now 3/4 of those in your list fall in that range :)
 

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is a continuous duty diesel marine/industrial more stress than an on-road automotive type?

what are your experiances towards this? id like to know how/why. if thats the case then why are marine/industrial units have higher available hp/tq???????? you could get a 1987 marine 6bt w 210hp.... i dont think you could get an auto one till 1998????

92 W350, Getrag, 3.54 gears, PDR Cam, POD's, HTT Stage II, Pump tweaked, 3200 gsk, 1/8" advance, 4" Exhaust.
Tested at 4600 feet elevation, 75 degrees, in 4th gear on Mustang Dyno.
Uncorrected 191 HP, 472 Torque;
thats 121 at the rear wheels with a 4bt (2/3 theory), rotary pump...... lots of mods? or not? the turbo should be about 900, the cam $1000, injectors 400. for 2300 dollars i would buy a 6bt and have at least that..........
 

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is a continuous duty diesel marine/industrial more stress than an on-road automotive type?

what are your experiances towards this? id like to know how/why. if thats the case then why are marine/industrial units have higher available hp/tq???????? you could get a 1987 marine 6bt w 210hp.... i dont think you could get an auto one till 1998????
Automotive: In most cases, cruising in a car/SUV/4x4 doesn't require much HP. Most of the time we spend on the road is cruising, with high acceleration/decel being relatively unfrequent. I had a little Mitsu Eclipse with a 4 banger with a blown head gasket between two cylinders - I had no problem cruising at 70MPH on the highway on two cylinders (~40 HP).

Boats: You need a lot of HP to overcome water friction. When your boat rises over the water, then your power needs go down. Recreational boat guys with automotive V8's wished they got the same gas mileage as an SUV...


thats 121 at the rear wheels with a 4bt (2/3 theory), rotary pump...... lots of mods? or not? the turbo should be about 900, the cam $1000, injectors 400. for 2300 dollars i would buy a 6bt and have at least that..........

If that guy has had to spend that much $$$$$ to get 180HP out of a VE 6BT, he's been doing something wrong.
 

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Automotive: In most cases, cruising in a car/SUV/4x4 doesn't require much HP. Most of the time we spend on the road is cruising, with high acceleration/decel being relatively unfrequent. I had a little Mitsu Eclipse with a 4 banger with a blown head gasket between two cylinders - I had no problem cruising at 70MPH on the highway on two cylinders (~40 HP).

Boats: You need a lot of HP to overcome water friction. When your boat rises over the water, then your power needs go down. Recreational boat guys with automotive V8's wished they got the same gas mileage as an SUV...
that answer has nothing to do with what i asked.

If that guy has had to spend that much $$$$$ to get 180HP out of a VE 6BT, he's been doing something wrong.
ok, show me some dyno runs with a FIRST gen (ve) dodge 6bt producing 225hp at the rear wheels for less money. and water/methane is ok, but id prefer mechanical.
 

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they run different turbos (how much for that?)
different injectors (how much are those)

i dont want to he said/she said. like i keep saying. i just want someone to do it. everyone that says its easy, cheap, and reliable has yet to do it with a 4bt.

all of the comparisons are on a 6bt. im still not convinced its a <1000 swap

meby spent $775 (and his pump dies, for who knows whatt reason) and said he had tthat much with a "butt dyno". im not saying its impossible. im not calling you or anyone out.

keep up you expenses (minus labor even) then post the dyno results.....

i may dyno mine one day.....
 
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