ISF2.8 Data Points on Drive-Ability

brdhmltn

Well-known member
70 mph @ 2400 rpm cruise
transfer case moved about 6" rearward

Mined From the Axis Industries Instagram feed & interwebs searches:

Defender Stats:
3.54 Axles
1.4 LT230
8HP70 auto from RAM 1500

TORQUEFLITE 8 (8HP70) RATIOS
1st 4.71:1
2nd 3.14:1
3rd 2.10:1
4th 1.67:1
5th 1.29:1
6th 1:1
7th 0.84:1
8th 0.67:1
R 3.3:1

many many people have said the ZF 8speed is the magic transmission for this engine.
" 2200 at 75 is perfect imo" for fuel econ and overall feel cruising
 

Red90

Well-known member
Maybe, but their build of that truck must be pushing $100k...... Not exactly the everyman's way to go. We need to start seeing the non-gold plated conversions....
 

Mack

Active member
One thing I am interested in is using the 8hp70 in a 90. As much as I like the idea of using the r380, the 8 speed will hold up to a tuned r2.8 where the r380 will be near its limit with the stock tune. Axis says they moved the t-case back about 6” when using the 8 speed. They suggested the 8 speed may not be usable in a 90 since that would make the rear driveshaft very short.

They posted a picture and proposed the idea of making new rear engine housing that the transmission will bolt straight onto as opposed to bolting an adapter to the standard Cummins rear housing. That would save about an inch, and would come at the cost of needing to remove the oil pan to get it installed, which isn’t a huge deal to me.

Companies like Rakeway UK make a short output for the LT230 which shortens the rear output by 70mm. With the shorter rear housing/adapter and a short output on the t-case that brings the total added length to approximately 55mm or just under 2 1/4” if my maths are correct. Shortening the rear driveshaft on a 90 that amount shouldn’t be an issue, right?
 

NPT90

Well-known member
Maybe, but their build of that truck must be pushing $100k...... Not exactly the everyman's way to go. We need to start seeing the non-gold plated conversions....
Pretty much my take on the whole 2.8 Cummins debacle. That said, the R&D of the early adopters should make for a reasonably priced kit when my 300TDI shits the bed. Cheers for that!
 

brdhmltn

Well-known member
Axis did a lot to that truck that a regular guy wouldnt have to. The intake parts could be different, trick radiator / intercooler setup isnt necessary.
The major costs for a regular guy would have would be engine, trans, two adapters (engine to trans, trans to tf case), new driveshafts, control electronics for trans. Still a lot, but on the order of $15k (no labor or home labor) and it doesnt have to result in a $100k truck after.
I'm doing R380 to cut the changes (cost) down, and because I want manual. My main excitement about this is that Axis is driving the truck and answering questions. They have experience driving that engine in a lot of jeeps and now a 110. So I consider their opinions good reference for determining gearing choices. I was worried if my costs were going to inflate because 3.54's wouldnt be good or I'd need to get the 1:1 LT230. I have a 1.2 and 1.4 here already. This is enough to let me know I'll be fine with the parts I have to start.
 

Red90

Well-known member
Pretty much my take on the whole 2.8 Cummins debacle. That said, the R&D of the early adopters should make for a reasonably priced kit when my 300TDI shits the bed. Cheers for that!
I think the path Doug is taking can make it cost effective. You can more or less drop the engine into a pre-200TDI truck with his bellhousing and suitable clutch. If you blow up the LT77, then switching to a HD R380 is simple enough. The next thing that is needing is plug and play engine mount, a reasonable intercooler rad setup with pre-made plumbing. If it were me, I'd start with a TD5 setup as that should drop in and the intercooler ports are on the right sides.
 

Red90

Well-known member
....the 8 speed will hold up to a tuned r2.8 where the r380 will be near its limit with the stock tune.
There are literal a thousand trucks running TD5s with more torque and power and not blowing up upgraded R380s. If you really feel like driving it roughly, put in an NV4500. It is a lot more work, but tons of them have been installed in Defenders.
 

NPT90

Well-known member
Debacle ? I must have missed something, somewhere.
Engine has been available for over a year and while there has been a lot of conversation, expensive adaptors, R&D and all of that I have yet to see a comprehensive post of the swap or any real world use. After all the hype I would say that is cusping debacle (as stated above, in my opinion).
 

JimC

Well-known member
Heck of a lot better than the 2.8 TGV debacle. That still took more than a year to get conversions in the wild and bunch of engines were defective.

The Cummins 2.8 that I drove at MAR was awfully nice...
 

Uncle Douglas

Well-known member
The Cummins 2.8 that I drove at MAR was awfully nice...
Thanks, I'll take thats as a thumbs up from someone who has built a defender from the ground up and can appreciate what was actually involved in noodling that out, making or having the parts made, and then building it. From above comment apparently its not legit because there isnt a comprehensive build thread where experts could comment, and the owner feels no inclination to do one on his use of the truck either.

I guess in todays "entitled" times the time it takes to develop applications and adaptations is expected to have been done by someone somewhere in advance of an engine being released/becoming available. I guess what most would view/consider developmental teething by people with the skill set to do so, arm chair experts with no skin in the game, view to be a debacle.

FWIW there were multiple completed Cummins R2.8 110's @ Expo East last fall.
Just because its not posted on a forum inviting miscreants comments, doesnt mean it isnt/ hasn't happened.
 
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rocky

Well-known member
I hear you Doug. four years after putting my truck on the road from a collection of parts, I'm still finding opportunities to refine/fine tune it.
 

Uncle Douglas

Well-known member
Rocky to answer your pm question, the 6 spd auto Cummins 90 we built this time last year wont be @ ROMP, owner is bringing a different truck.
He's got 4 defenders here with us presently, guess he liked the first one.
 
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brdhmltn

Well-known member
FWIW there were multiple completed Cummins R2.8 110's @ Expo East last fall.
Just because its not posted on a forum inviting miscreants comments, doesnt mean it isnt/ hasn't happened.
It's apparent to me everyone is frustrated about the situation. I feel you. I'm frustrated. I really don't like thinking that unlike jeep drivers, land cruiser drivers, fj drivers and may others, I cannot just buy a kit online today. Rover guys had the same early access the jeepers did... still no parts for sale. I went from having a pregnant wife to now have a walking, talking daughter I can have conversations with. Engine has only moved from one garage to another.

I fully recognize and admit I'm an idiot for ever thinking my truck would get the same attention as a land cruiser. $10k worth of idiot for 13 months +, right here. 🙋‍♂️ I have to live with the fact that engine may rust into a dust pile before any part is for sale, but hey, had I only paid $30k more to a shop, I could have had it all last fall man.
 

rherl

Member
Having almost finished a from scratch build of a 110 that has taken nearly 5 years to complete I have a great respect for the guys who are pioneering these conversions. My truck is a 200tdi with new chassis, new puma body, new wiring etc. The only thing not new is the drive train. I have learned the hard way that there is so much involved in building one of these things even with known components. Now add a new drive train and I have nothing but respect for Doug and the others who are developing this motor to be able to work in the Defender. Doug, Robert, Safari, and all the others are truck builders out there are not component builders. What trickles down from their $100K trucks is great for the community and they will eventually come. Looking at other threads it looks as if a pretty easy conversion is around the corner for the 200tdi and earlier crowd. I think its hard to compare the Jeep and Land Cruiser aftermarket to the Defender aftermarket. With millions of Jeeps available and hundreds of thousands of Cruisers avalaible there is bound to be a robust aftermarket for these vehicles. Now how many Defenders are there really in the US? I'm not sure but guessing somewhere under well under 100000. There is not a lot of incentive to develop parts for the small percentage of those Defender owners who want to do this transplant. If I'm a guy who wants to build parts for these Cummins transplants I'm going to first focus on Jeeps, then on Cruisers, and when I run out of things to do there then maybe the Defenders. Also there is a large group who don't want the 2.8 and instead want an LS in their truck. so that pulls some of the already small market away.

While I like the Cummins and am still considering it for my next build after I sell my 200tdi, there are many ways to skin a cat. Cummins, tuned 300tdi and 200tdi, Roberts strait 6 conversion and Mercedes conversion, TD5, 2.2, 2.4, 3.2 TDCI. Currently I am leaing towards a TDCI for my next build because it is a proven platform that will require little fabrication on my part to make it work and it can be tuned effectively to make the power I want. But I will be building it from the gound up again so I am not constrained by seat box, bulkhead, and transmission tunnel issues. I am personally not frustrated but encouraged by the innovation of these guys. Once they have a product that they can reproduce consistently and start to get caught up with the clients who are willing to pay for their builds services then those products will come to us home builders. Until then they deserve our encouagement and praise for the inovations they are making in a very small, very expensive and very exclusive truck market. The reason we all have defenders is because they are exclusive. If we wanted to drive a Jeep we could have off the shelf products right now for our Cummins transplant. But since we like that exclusivity we need to either be patient, shell out the cash needed to have a build done or turn into the innovators ourselfs.

To Doug and the rest keep up the great work!
 

Overlander

Well-known member
The reason we all have defenders is because they are exclusive.
Not true. Speak for yourself on that one. I choose a 110 because nothing else fits to my needs. I'd be happy if every 3rd vehicle in traffic with me was a Defender.
 
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