Thread: fairey overdrive

Originally Posted by RaggedJoe

Thanks John.

Might push her a bit harder next time out! But 110! The noise of all the things you mention would be enough to put me off, and stopping her from that pace in an emergency with LT tread on the tarseal, well let's just say I think it might be a challenge! Front mounted handwinch vs unwary Japanese hatchback / pedestrian doesn't bear thinking about.

When my IIA had a 2.25P, I could sit on >75 MPH! on a flat highway if I wanted to (no OD at that stage). 75 was as high as the speedo went... The needle was about where 80 mph would be if the markings had continued.

Even with a 2.25D and no OD (but with earplugs!)

Originally Posted by isuzurover

When my IIA had a 2.25P, I could sit on >75 MPH! on a flat highway if I wanted to (no OD at that stage). ...
... Even with a 2.25D and no OD (but with earplugs!)

and not minding that the car would be jumping all over the road!

My 202 powered SIII, no O/D will easily do 115KPH, so long as I can stand the flapping of the tarp.

Originally Posted by Lotz-A-Landies

and not minding that the car would be jumping all over the road! ...

If you have stiff springs, skinny rag tyres and and no load then maybe...
My IIA with soft springs and 235 or 285 radials has always handled quite well on the highway.

I had a fairy O/D on my SIII 109, and it was happy to cruise at 110kph on the flat.

I don't think it would cope well with bigger tyres.

They lose a lot of oil through the pin hole sized breather. I drilled it out and fitted a larger breather that was in common with the t/case. Better still would be one that drains back to the o/drive. It ran on Moreys, as it had some wear when I bought it, but that worked pretty well. Even though there was a slight whine, the 28% drop in revs and engine noise still made it worthwhile.

The 110 300Tdi has a Roverdrive on it. At 100kph the wind buffeting the snorkel is the loudest noise in the cab. At that speeds the Tdi is doing 2,000rpm. The only issue with the Roverdrive has been the lever's occasionally knocked into neutral on bumpy steep ascents.

As for top speed and handling, I had a 3 litre Nissan Diesel and 5 speed in a SIII 109 at one stage (Do NOT do it!!!). I can say the car was still stable and predictable on the road at 140kph (in the NT when it was legal).

thanks for the replies guys, much appreciated. I dont think i will worry about the overdrive. especially with 35s i dont need any other weak links in the driveline.

Originally Posted by isuzurover

A 2.25 would seriously struggle with 35s AND an OD.

The fairey OD is noisy and weak. The Toro is quieter and slightly stronger. The roverdrive is better again, however if you are spending Roverdrive money, you would be better off with an R380 5-speed conversion.

Where do I get an R380 5 Speed conversion.
I am in the thro's of "about to" order a "Roverdrive"

Originally Posted by JDNSW

Manufacture of them by Rovers Down South ceased in December last year (see Rovers Down South Fairey Overdrive) so there is no 'new' price.

Second hand ones go for somewhere round $500-$1000. Mine cost $500 with a Landrover attached, but I had to spend nearly as much again on parts. Most parts are available, but many of them are expensive.

How strong are they? They generally withstand operation OK for standard Rover engines, provided they are only used in third and fourth gear. Operation in first or reverse can easily break them if used with full throttle and a sudden load such as losing and then gaining traction. But no different if used in low or high range.

If buying one second hand, ensure that all parts are there. Likely to be missing is the linkage and bracket for this, and the drive dog that replaces the gear on the mainshaft of the gearbox.

Problems. The oil reservoir is small, and oil can be chucked out the breather - I extended the breather. Oil level must be checked regularly, especially if the overdrive is used on the highway. The drive dog is susceptible to wear, and will eventually lose drive totally. While the dog is only US$125, the bit it engages with is the mainshaft, which is US$350, and wear takes place on both.

In my view, having had one for a number of years, I would not get one again. The Rover engines are quite happy to turn at the required revs for the 110kph speed limit, and the lower rpm resulting from the overdrive is only a slight advantage.

My advice would be that if you have a Rover engine, either four or six, forget the overdrive - its only real advantage is as a splitter, especially in low range. If you have another engine, perhaps look for another type of overdrive, although these are rarer and more expensive. For example Heystee Automotive Online Store

John

So John...what do you recomend..."Heystee" or "Roverdrive" ????????

I am about to order one for my Series 3!


Cheers, Mick.

Originally Posted by mick88

Where do I get an R380 5 Speed conversion.
I am in the thro's of "about to" order a "Roverdrive"

1. Find a defender R380 for sale at a reasonable price.
2. Buy a "stumpy" R380 bellhousing from Ashcroft. Ashcroft Transmissions - Short Bellhousing R380
3. Do the mods to fit an LT230 t-case, or buy a 2nd adaptor from ashcroft:
Ashcroft Transmissions - Series 5 speed kits

Note that is you can find an LT77 5-speed from a 200Tdi defender that will replace steps 1 and 2, but the LT77 is not as strong.