LT77 into SIIA 88" ?

[Dauntless]

How much work would it be to fit a LT77 or LT77S into my Series IIA 88" ?

It would be fitted to the original 4 cylinder petrol engine. I'm not sure which transfer box I would use, whichever works and fits best I guess.

Ideas?

Thanks.

[JDNSW]

A lot of work.

Fit a transfer case - and the Series case I do not believe is a bolt on fit - anything else that is a bolt on fit is set up for full time four wheel drive, which means either converting the front axle to suit this or converting the transfer case - both are major jobs.

New prop shafts, front and rear - the gearbox length is different. Rear prop shaft may be getting a bit short for comfort, depending on the transfer case.

Design, make and fit new handbrake linkage.

Design, make and fit new floor and transmission tunnel panels.

Modify seat box for new floor.

Design, make and fit new gearbox mounts.

If the box fitted is off a 200Tdi, then the bell housing should fit - if not, it won't.

In summary, it can be done, and probably has been when fitting a later engine, but would be an awful lot of work.


John

[Dinty]

G'day All, John has covered it very well but forgot to mention the added burden and $$$$$$$" in cost to have it all certified by a qaulified/approved RTA engineer, that in itself is a big hurdle.
I like the idea of late model engine/transmission into the Series 2A but geez it's a lot of time/effort/dollars anyway mate it's your baby cheers and all the best with it, Dennis:wasntme:

[Lotz-A-Landies]

How much work would it be to fit a LT77 or LT77S into my Series IIA 88" ?

It would be fitted to the original 4 cylinder petrol engine. I'm not sure which transfer box I would use, whichever works and fits best I guess.

Ideas?

Thanks.
Don't be daunted by the neigh-sayers, both the LT77 and R380 gearboxes can be mated to the series transfer box using a conversion kit from Ashcroft's in the U.K. Ashcroft Transmissions - Series 5 speed kits (http://www.ashcroft-transmissions.co.uk/part_66.html). The cost will be the killer of the project as the price is over $A700.00 before you ship.

It has the advantage of a stronger overdrive gear than using a Fairey, but you still lose your rear PTO capability.

I'm not sure about how the LT77 mounts to the 2 1/4 litre however as it was the basis for the design of the Tdi series engines it's probably O.K.

The big problem is that it makes the gearbox 102 mm longer, which makes for very short rear prop shaft. Ashcroft's recommend moving the engine about 4" forward, which would be similar to the modifications necessary for the Holden conversions.

Engineering should not be an issue.

Diana

[isuzurover]

I'm not sure about how the LT77 mounts to the 2 1/4 litre however as it was the basis for the design of the Tdi series engines it's probably O.K.

In OZ, LT77s were only fitted to V8 rangies. V8 and 200 Tdi Discos and 200 Tdi 110s (All of these had the LT77S which was slightly upgraded).

Only a 200 Tdi box will bolt straight up to a 2.25 (I think one stud needs to be removed or a hole for it drilled). However, AFAIK the disco versions have the selector in the wrong place, and it isn't worth changing. So - bottom line is - only a 200 Tdi defender box will be an easy fit.

V8 boxes (most common) have a smaller spigot (input) bush (- no big deal), but the bellhousing bolt pattern is quite different.

The V8 boxes also have taller gears (1st-3rd). However you can fit a tdi bellhousing to a V8.

AFAIK the R380 requires a bit more work to fit, but I think it is only drilling and tapping a few holes.

[Slunnie]

In this conversion, would you leave the diffs as 4.7 due to the power (or lack of) from the 2.25 despite that gearbox being mated to the 3.54 diffs normally?

[isuzurover]

In this conversion, would you leave the diffs as 4.7 due to the power (or lack of) from the 2.25 despite that gearbox being mated to the 3.54 diffs normally?

I think that would be best, as you aren't making 1st gear any lower. However, you are going from a top gear ratio of 1x1.18x4.7 (=5.55) to 0.77x1.18x4.7 (=4.27), which would be a big step up! The defender is a bit taller again (0.77*1.41*3.54 = 3.9)

[Dauntless]

Hmm, interesting. Thanks for that.

So far the only things that worry me are modifying the floor and trans tunnel, and the length of the tailshaft. Yes I would personally leave the 4.7 diffs. Even if I end up using a 4 speed I will still keep the 4.7's.

[isuzurover]

Hmm, interesting. Thanks for that.

So far the only things that worry me are modifying the floor and trans tunnel, and the length of the tailshaft. Yes I would personally leave the 4.7 diffs. Even if I end up using a 4 speed I will still keep the 4.7's.

If you buy the ashcroft adaptor and move the engine 4" forward, then the tailshafts (and entire t-case and mounts) stay as they are. Fabricating a new tunnel isn't a huge job.

[Disco Steve]

Sorry to hijack, but what boxes would bolt to a 2 1/4L?

Cheers Steve

[Lotz-A-Landies]

I think that would be best, as you aren't making 1st gear any lower. However, you are going from a top gear ratio of 1x1.18x4.7 (=5.55) to 0.77x1.18x4.7 (=4.27), which would be a big step up! The defender is a bit taller again (0.77*1.41*3.54 = 3.9)
This jump is not too bad and is similar to the old practice of using the Rover car 4.3:1 diffs. without the disadvantages of the tall 1st gear Low range.

On a 2 1/4 engine it would be used as a true overdrive where 5th would only be selected at highway speeds probably over 80 KPH. The issue would be the comparitive spread of the 1st to 4th gear.

Diana

[JDNSW]

Sorry to hijack, but what boxes would bolt to a 2 1/4L?

Cheers Steve

Without adapters, only Series 2/2a/3 boxes originally fitted to four cylinder petrol and diesel engines engines, plus those fitted to the 200Tdi (which is where this post started).

The problem is not so much fitting to the engine - engine/gearbox adapters are mostly pretty simple - but fitting to a transfer case and then the overall positioning of the prop shafts, controls and changes to the floor etc. Several people in this forum have, I think, fitted completely foreign boxes, usually with another engine, although the problems are the same sort as fitting automatic gearboxes to Defenders for example, and there have been a few of these done.

John

[Dauntless]

Fair enough. So are there any other Rover boxes I should consider?

Is it possible to rebuild the stock Series box to hold a bit more power?

[Dauntless]

Nobody?

[Lotz-A-Landies]

Fair enough. So are there any other Rover boxes I should consider?

Is it possible to rebuild the stock Series box to hold a bit more power?
The only other Rover box you may consider is the late series 3 - the one with the lattice work down the casing. Still not a strong box but the layshaft is 1 piece and they don't throw the reverse idler out the side of the case.

It also doesn't have an overdrive 5th gear (or any 5th gear).

Diana

[JDNSW]

The Landrover Series box was, I believe, introduced in 1932 as a car gearbox. It first appeared in Landrovers in the 1948 Series 1 behind a 1.6 litre engine producing 52HP. With minor changes it continued in production until the introduction of the Series 3, when it was redesigned with synchromesh on all forward gears. Unfortunately, the need to fit more works in the same space meant this gearbox was weaker than its predecessor (and it can be suggested that some errors were made in the redesign). Minor changes followed and as Diana points out the, last of these was the strongest, although it is a moot point whether it reached the strength of the last of the older box (Series 2a suffix G on).

This box is adequate for any of the engines it was fitted to the Series Landrovers except the V8, but it is worth noting that Rover was not prepared to put it behind even the derated version of that fitted to the Stage 1.

The introduction of the 90/110 brought a five speed gearbox, and the new chassis design allowed more space to be allocated to the gearbox, easing the problem, helped by the extra four inch wheelbase on the 90 compared to the 88 (actually there is even more space than indicated by this, because the chassis is further forward on the wheels as well).

John

[isuzurover]

Still not a strong box but the layshaft is 1 piece


??? I pulled apart a suffix A series 3 box and it had a 1-piece layshaft. I thought they all did.

The late model IIA box with the correctly radiused layshaft is the strongest IMHO. The layshaft broke in mine (probably during army service) and was replaced by the revised one. Apart from general wear and tear, and breaking inferior 1st gears (beware poor quality aftermarket parts!), mine has held up well.