Cummins 6BT Conversion

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you may well be able to sell whats left of the truck to dr.evil, send him a pm.

he says he's been offered a couple of water damaged 777 engines for a really good price and is going to build a twin engined jet truck.
 
Nah don't want channel, using brand new full box section and its already paid for although for the right price I'd probably be interested in the rear leaf springs and possibly front if its still on them too.

Saves me going down the yard and haggling with the local guy
 
Nah don't want channel, using brand new full box section and its already paid for although for the right price I'd probably be interested in the rear leaf springs and possibly front if its still on them too.

Saves me going down the yard and haggling with the local guy

why, box tubed? Them C channels will be stronger than a box section
 
Box section actually has better torsional loading from memory, as to the rest it wont make a difference once its been braced and had a couple of diamond plates placed along the boxes weld lines which would be the only weak point.

The idea is that with the box section it'll be capped off with one decent sized drain hole at the lowest point and therefore pretty damn hard for water to get in once its galved given that the only open point will be the bolt holes for the engine mounts and they'll be sealed up.
 
c channel is not stronger than box, but its better for truck chassis as it can flex

from what I read pound for pound c is stronger. and like you said flexes and has better memory where box will kink and the you are fooked. No flex and thing brakes and tear.
Lorries and there trailers a c frame and I beam frames for a reason
 
box still flexes just not to quite the same extent but this wont be towing a 40 tonne trailer behind it, plus C or U depending on what you want to call it also has a large pocket for ****e to sit in and given that I live in cumbria where the roads are very heavily salted from november to mid march anything that gives that crap less places to sit is a winner!
 
You are correct in saying that im not a regular contributor. Thats fair enough, but we've all got to start somewhere right? Its a bit presumptious to say i dont listen. I listened to everything you said. Even though i pm'd you offering money for your help as i didnt want to blag your time. I admit im not an expert. I even said that at the start. But at the end of the day i dont have a big fully-equipped workshop with lathes, drills and welding gear to start learning how to fab etc. I appreciate you saying that my intended setup is not up to the tuned cummins, but like i said i cant afford to change everything at once.

Here's my thoughts... Listen to Pressbrake and a few others.. You are talking big power before you have experienced std power from a Cummins 6Bt.. I completed a conversion fitting a Cummins 6Bt and ZF 5-42 gearbox coupled to an LT230 into my 101FC. When I finished building it a took it for its first test run.. without the speedo connected along with a few other things... To be honest, I was not wowed by it like I thought I'd be.... Now I've got used to the shear torque from this engine, and have given the injection pump one full turn of the fuel screw to suit the intercooler I've added, I now can't get over how well it goes.. Assuming the Daf 45 engine was 130hp, and with an intercooler and increased fuel Im now guessing its at approx 150/160hp.. It flies! The torque is awesome (and smooth not like a course 4 cylinder), and it also seems to pull right up to 3000rpm. Do I want more power now? No. It does not need it. Really, it doesn't! It gets to 100kph very quickly, sounds awesome, seems good on fuel, and so far the trans etc is surviving (I did add an Ashcroft one piece center diff cross shaft and an increased capacity sump to help the LT230). Some facts.... The ZF 5-42 (5 speed, 420nm of torque) box is user friendly in a forward control but you'd need the US top shift to run it in a Defender. The Cummins is big, and it is a lot of work... Bespoke engine and chassis mounts, sump reversal inc oil pick up, serious machining to get the ZF to fit the LT (inc gear welding if you go down my route).. Props cut and shut, front springs beefed up, exhaust manufacture, rad mods or larger rad, sound proofing (LOTS!), and then you have the 12/24v issues.. (I've run 24v start and charge, running 12v for the vehicle. This can be done easily using two decent relays and a separate 24v charge light). You have a lot to think about, a lot of work to do, and if you are not a proficient engineer as you have said you are not, then you need quite a bit of money to spend... Pressbrake has hinted at this, and Im telling you the same.. Be sure you want to attempt this conversion as a £1500 weekend TDi conversion it is not! Good luck! :) Oh, and here's a shot of the ZF to LT under my 101!
 

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Well ive already got a megasquirted 4.6 RV8 so if i want to be "wow'd" (which i do) i may very well need to turn up the fuel/boost a little going by what you have described. In all honesty im a bit of a power freak so unless the Cummins conversion royally kicks the V8's ass i will not be starting it....
 
Unfortunately Nick's 6BT conversion has blown up its gearbox so it hasn't been on the road in quite a while.

He's also the cause of making me want a Cummins Landy though :p
 
Here's my thoughts... Listen to Pressbrake and a few others.. You are talking big power before you have experienced std power from a Cummins 6Bt.. I completed a conversion fitting a Cummins 6Bt and ZF 5-42 gearbox coupled to an LT230 into my 101FC. When I finished building it a took it for its first test run.. without the speedo connected along with a few other things... To be honest, I was not wowed by it like I thought I'd be.... Now I've got used to the shear torque from this engine, and have given the injection pump one full turn of the fuel screw to suit the intercooler I've added, I now can't get over how well it goes.. Assuming the Daf 45 engine was 130hp, and with an intercooler and increased fuel Im now guessing its at approx 150/160hp.. It flies! The torque is awesome (and smooth not like a course 4 cylinder), and it also seems to pull right up to 3000rpm. Do I want more power now? No. It does not need it. Really, it doesn't! It gets to 100kph very quickly, sounds awesome, seems good on fuel, and so far the trans etc is surviving (I did add an Ashcroft one piece center diff cross shaft and an increased capacity sump to help the LT230). Some facts.... The ZF 5-42 (5 speed, 420nm of torque) box is user friendly in a forward control but you'd need the US top shift to run it in a Defender. The Cummins is big, and it is a lot of work... Bespoke engine and chassis mounts, sump reversal inc oil pick up, serious machining to get the ZF to fit the LT (inc gear welding if you go down my route).. Props cut and shut, front springs beefed up, exhaust manufacture, rad mods or larger rad, sound proofing (LOTS!), and then you have the 12/24v issues.. (I've run 24v start and charge, running 12v for the vehicle. This can be done easily using two decent relays and a separate 24v charge light). You have a lot to think about, a lot of work to do, and if you are not a proficient engineer as you have said you are not, then you need quite a bit of money to spend... Pressbrake has hinted at this, and Im telling you the same.. Be sure you want to attempt this conversion as a £1500 weekend TDi conversion it is not! Good luck! :) Oh, and here's a shot of the ZF to LT under my 101!

I'm looking at a 101 6BT conversion... do you think looking at a remotely mounted LT230 would be worthwhile? It gets around a lot of the machining work. The only issue would be rear prop length.

How much rear prop do you have with the LT230 bolted to the ZF?
 
divorced lt230 to zf is a long beast so even with a 110 prop angles are on the limit

They wouldn't have to be very far apart, in theory you could make the prop just long enough for the boxes to clear eachother properly.

But yes I take your point... would be interesting to take some measurements and see what you'd end up with.
 
divorced lt230 to zf is a long beast so even with a 110 prop angles are on the limit

Langers, Pressbrake is on the money. 6Bt and ZF is already long. I studied Nicks conversion pics before I did mine, and knew it was going to be tight. I have sat the nose of the engine approx 100mm behind the face of the radiator (still in its original location) so I could fit a decent engine driven fan.. I recommend the engine being as far back as possible in a 101 or the rear wheels will forever be off the ground. I also recommend a driven fan. My rad is still a std 3 core, just with larger inlets, both on the right. With the LT230 close coupled (25mm piece of plate bolted direct to the ZF and LT), I still had to modify the cross member behind the gearbox. The handbrake drum now sits directly under it. The rear prop is approx 400mm long. To get this to work, I've tilted the engine to the rear, lowering the tail of the transfer case but also allowing clearance above the front axle. I've also removed 8mm from the front of the axle plates on the rear axle, which has allowed the nose of the rear diff to lift by approx 20mm. The rear prop now runs well. This has its disadvantages tho.. The front prop is on its limits of working angles at the front transfer box output flange.. I've not used wide angle joints tho on the front shaft as I cut down a 110 rear prop, so I still have the double cardon option if needed. We are seeing how we go at the moment.

MayorQuimby. Diesel power is not V8 power.. If you want that extreme, then you're better off finding a huge petrol lump or a bells and whistles lightweight V8 diesel from the German or Jap stables...
 
Langers, the other thing that is needed in a 101 is that the engine you choose must have the Bosch VE rotary fuel injection pump.... If you use an engine with the larger in line injection pump, it will mean one of two things... Either your passenger is going to have a lump in the right of their seat base or you will have a front diff contacting the sump/block... Not good on a 6Bt as the sump oil pickup is in the very front right corner of the block!! Bear in mind also that the LH side of the engine needs to be as clear as possible as you need it to sit as far to the left to allow sensible prop angles on the right... I had to make a cut out in the cab spar behind the front wheel for the compressor head to clear (retain the compressor... You will need it to drive the air clutch especially once you've replaced the original 3/4" clutch slave cylinder with a 1" Ser 2 LWB brake master cyl!!) I also had to modify the inlet manafolds to clear the engine cover... as pictured! (Yes the engine cover support angle is cut out to clear the rocker cover! ;))
 

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...MayorQuimby. Diesel power is not V8 power.. If you want that extreme, then you're better off finding a huge petrol lump or a bells and whistles lightweight V8 diesel from the German or Jap stables...

I know what you mean, but at the end of the day horsepower is horsepower, and torque is torque. Just produced in a different way. I know it will have to be driven differently as the Cummins will only go to a max of 4k (with different governor and valve springs) but regardless an engine producing 500 lb/ft will still accelerate quicker than an engine producing 320 lb/ft. If driven correctly of course ;)
 
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