R2.8 to Ashcroft HD R380 stumpy Conversions

donb

Well-known member
?? The input shafts are not the weak link. Ashcroft installs larger layshaft and mainshaft rear bearings. This has nothing to do with the input/pinion shaft. The input shaft is changed in order to make the box shorter, so that the engine clears the steering box. This make it the same overall length as the short LT77s.

Yes - I said ?If? the input shaft was the weak link. I wasn?t sure what Ashcroft?s exact formula for the HD R380 for the R2.8 was. I could have sworn UD posted on another thread that Ashcroft was making R380?s even more robust for his R2.8?s installs. But I could have mis-interpreted something I read on that other thread.

I know the input shaft is changed in order to make the box shorter. I have a shorty R380 behind my 200tdi.


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Uncle Douglas

Well-known member
We had an email exchange with Dave about having our own stronger main shafts made.
He indicated the shaft wasnt the problem, the shaft moving around was the problem, and that modifying the case for the larger bearings solves the issue. He indicated that the transmissions with his HD bearings are holding behind Twisted and others highly modified td5 trucks making 400 ft lbs or more.
 

donb

Well-known member
We had an email exchange with Dave about having our own stronger main shafts made.
He indicated the shaft wasnt the problem, the shaft moving around was the problem, and that modifying the case for the larger bearings solves the issue. He indicated that the transmissions with his HD bearings are holding behind Twisted and others highly modified td5 trucks making 400 ft lbs or more.

Thanks Doug :thumbsup
 

Uncle Douglas

Well-known member
We are able to supply stumpy gearboxes without the bell housing for 845 outright, each.

Kind Regards

Hosanna Dowling
Ashcroft Transmissions Ltd


Add 160 for the modified case and bearings and the transmission is $1270 plus shipping.
 

Roverman2010

Well-known member
John,
I'll let you know. Had emailed Hosanna @ Ashcrofts asking if they'd like to buy the 4 back.
Doug, don't worry about it. Just took stock I have a rebuilt 77 and two waiting to be gone through. And two 380's on the shelf. I think I have enough 77's to last me for old red. Just out of interest what is the height/width of a stumpy b/h. Engine side to gearbox. Thanks
 

Overlander

Well-known member
Chris wants new threads so going to splinter off and document what we are doing.
I'm not in love with using automatics behind diesels. Maybe its just me being old school. I built a v8 manual trail 90 just to force Trey to learn to drive a stick. To me the much greater compression braking you get from a diesel that is only able to be utilized with a manual is a big deal, and then there is economy/range is important.
We have 5 spec built radiators and intercoolers now ready to ship to us after a long wait. After meeting with Steve @ the Cummins booth @ Expo East I got in touch with Chad Mckinney/Quickdraw Brands and got him fired up to develop a custom bell housing for the short R380. I did this based on others he had on display in the Cummins booth. He's having a prototype cut out of a billet block for me and expects to have it in my hands third week of January. We are going this route rather than wait for castings which will likely take until March. A new bellhousing is a better mousetrap than trying to utilize an adapter ring and allows us to use the flywheel Cummins supplies with the engine.
I sent him a stumpy as well as a Rover clutch but asked that he figure out the largest beefiest clutch disc that had the same spline configuration as the Rover trans. He laughed when he saw the stock Rover 4cyl clutch disc I sent him for mock up. Chad found that an early 70's Chrysler V8 clutch disc fits perfectly so we will be using these readily available off the shelf, complete 70's muscle car clutch setup with these Cummins to R380 kits.
Once we've got this dialed in, a diy'er you will be able to purchase an off the shelf kit from Chad @ Quickdraw.
In the future the stumpys we order will be sans bell housing which should help a good bit with the price from Ashcrofts.
You're my F'n hero Doug.
 

rlynch356

Well-known member
just for future thought doug, could this be used to convert my V8 1992? assuming a new stumpy transmission, the new bell housing etc.. mine has been converted already to a 3.9 and R380 though(including tunnel and seatbox from the looks of it) ... eventually i'm going to change it for something more powerful.
 

Overlander

Well-known member
Doug, have you talked to Axis about using the upgraded HD Ashcroft R380? After the email from Kevin at Axis today, I had an email exchange asking him about that, since they are backing off the R380. it's still not clear if he understood Ashcroft offers the HD. I like him choosing a bulletproof route, but I"m still unclear how durable Ashcroft's R380 will be.

I really want an overland ready, durable, reliable tranny that is EMP proof and ready for overlanding in developing countries with parts supports if needed. This is really the only unknown for me in my next build.
 

Red90

Well-known member
An NV4500 will be a large project with a ton of modifications to fit. Watching Axis' build, they are targeting the unlimited budget customer. They are putting insane money into the truck they are building. If that is you, go their route.

The point of the stumpy is it basically a straight drop in. It will be fine unless you like to abuse your truck.
 

Uncle Douglas

Well-known member
Doug, have you talked to Axis about using the upgraded HD Ashcroft R380? After the email from Kevin at Axis today, I had an email exchange asking him about that, since they are backing off the R380. it's still not clear if he understood Ashcroft offers the HD. I like him choosing a bulletproof route, but I"m still unclear how durable Ashcroft's R380 will be.

I really want an overland ready, durable, reliable tranny that is EMP proof and ready for overlanding in developing countries with parts supports if needed. This is really the only unknown for me in my next build.
This was a marketing email. Kevin/Axis makes conversion kits, this is the direction he's chosen to take.
We build custom defenders, we are not in the conversion kit business.
Working with Axis and QuickDraw has been to develop parts for our builds.

I worked directly with Kevin for many mos, April- Nov to develop a solution to mate the r2.8 to the rover transmissions as you may know reading the other thread. As of Expo East I still didn't have a workable solution. I started this thread to document what I have decided to do based on the wisdom gained from that experince, and engineering now available to me.
Cummins was actually who introduced me to Chad Mckinney in November.

I have typed it out several times on this forum,but here goes again, after going back and forth with Dave Ashcroft, he indicates Twisted, Bell and others are running 400+ ft lbs through his HD version of the r380 without failures. No a stock or original r380 will not service the torque of the 2.8 for long, so what Kevin says there is correct. That's not what I'm doing.

A custom bell housing allows the use of a large off the shelf clutch, and mates right up to a land rover transmission specially built to handle to power. We now have 7 trucks waiting for these swaps so results/feedback will be readily available from clients in the coming months.

Chad has the first of these bell housings on its way to me with clutch etc. Should be here first of the week, right on schedule with our time line established back mid December.

I started this thread to indicate what we are doing, not as a round table on what others are doing, there is another thread running on this forum for that.
 

brdhmltn

Well-known member
I have faith in Quickdraw. Maybe I'll get my engine in before it's warranty expires. Something like 13 months in my garage at this point. I've honestly lost count. Yeay for early adopters. Yeay for Rover aftermarket.

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Overlander

Well-known member
Thanks Doug and my apologies for throwing off the thread. When Kevin stated he had worked with several defender shops and they collectively ruled out the R380, I wanted to get clarification if that included the HD ashcroft. He ambiguously responded that they won't go with the R380 without addressing that question. I wanted to make sure I wasn't missing some new information, as I suspected you may have been one of the shops. I understand the position now.
 

brdhmltn

Well-known member
FYI the kit is now available at Quickdraw. www.quickdrawbrand.com

I talked with Chad a couple of times on the phone today.
Clutch is from 70s early 80s Chrysler. He gave me the part number but I've forgotten as I didn't have a pen on me. Get the HD version. Non HD does not work. There are 2 kit versions. One where you send your flywheel to Quickdraw to drill the clutch holes and they return it, one with a print to carry your flywheel to a local machine shop to have the holes drilled. Balance is critical and take it seriously or you could damage your engine with an unbalanced clutch. If you don't understand, do the flywheel exchange. He does a steel insert that adapts the landrover crank bushing for use in the Cummins. It's part of the kit.

Chad gave Doug credit for getting this rolling. Chad didn't know about the Rover market before. I also give Doug a ton of credit for getting to a source that would provide these to everyone.

Excitement is back for me. With this I have the resources to handle all the rest.

Edited to fix the link. Sorry!
 
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