Sierra 5-speed conversion.

The Rovering Member

The Rovering Member

Well-Known Member
I've been advised that if possible, a Sierra 5-speed would be a good 'box to fit to my 2200TC due to ease of gearchange, compactness, availability & cheapness of purchase/spares. Can anyone advise if this is a feasible swap & if there is a conversion kit available. The LT77's are rising in price & are a bulky 'box & the Toyota conversion is just too expensive. My 4-speed needs work & I'm sure 5 speed is the right way to go for an everyday car.
I figure if anyone knows, one of you chaps will.
 
HI there are lots of V8 to ford adapters, the kit car industry loves the ford gearbox a quick search showed this one:

http://www.magnum-engineering.com/SVServRep/index.htm

However my 2.8 capri used to regularly pull these gearboxes apart leaving only fourth gear intact, so I am pretty sure the V8 would do the same.

As for four cylinder cars, there are conversion kits for the MGB, and the Rover M/T series twin cam engines (Robin Hood engineering do one I think) to take the sierra 5 speed box, It might be worth going down the M/T route, because then you get a nice modern engine with rover badges all over it, and the cheap ford box where no one can see it.

Alternatively if you dont mind a ford motor, there is always the 8V twin cam sierra unit (cant remember its name) , a much maligned engine in my opinion, 130 bhp, decent ammount of torque, simple fuel injection, fairly unbustable and basically you can get hold of them for peanuts if not for free if if you are prepared to take the rusty jelly mould that it is attached to, actually thats not a bad idea as you would get the gearbox and loom as well. hmm, anyone got a structurally sound dead P6 I feel a project coming on.
Cheers
Al
 
Thanks for the response Alimorg.
I want to convert my 4-pot 2200 to 5 speed so maybe the ford box would fare better than on a V8. Is there a conversion for this too? I'll have to do a little chasing up myself. I do want to retain the original engine as it is a lusty, rorty lump & I'll have no truck with cheap, modern abominations such as plastic cam-belts. I could accept a gearbox substitution but to put an '80's engine in would be, in my opinion, to lose the entire character of the car. A P6 should not be a P6 in appearence alone & that goes for any classic car as far as I am concerned, unless the engine is a direct descendant of the original, such as the 18V in my A60.
Talking of V8's, our new one was suffering from completely disintegrated (auto) gearbox mounts which gave rise to a rythmic thrumming which I at first put down to a seized universal joint as I suffered the same on my P5B a few years back & this proved to be the cause. On the P6 this turned to horrible vibration above 40 mph & a rough feeling when you started the engine. An auto specialist suggested I check the mounts & lo & behold they were both a soggy, disintegrating mess. If you have access to to the bottom of your car give them a check if you don't already know the condition of them. Weekley's sent me a pair overnight & I fitted them today though they are a little smaller & less robust in appearence than the originals which are actually bonded to the metal frame (you have to drill holes in it & bolt the new mounts on, similar to the rear spring mounts on the P5's). He said he only has them for the BW65 ('74 on) so if you have a 35 you'll apparently have to try someone else.
I have access to a wonderful pit at the moment which is just the right height for me & is the only place that I don't have a niggling doubt that the car is about to fall on me. I don't even trust 4-post lifts. I've replaced 8 UJ's in the past fortnight across my 3 P6's including both the prop' items on the V8 & sundry other tasks too. Bliss!
 
Hi There
I Think your best bet with the 2200 would be to speak to a local engineering firm, it would be quite easy for them (and probably cheapish for you) if you got them to knock up an adapter plate either to mate the ford bellhousing to the rover block or the ford gearbox to the rover bellhousing. The advantage you have with this option is that if you get a couple made up you could flog a few to recoup some of the costs.

The ford gearbox does have a sweet change, especially when you pop on a quickshift lever.

On the subject of gearbox 'feel' is it just me or do RWD boxes feel sooo much more positive than FWD?
Cheers
AL
P.S. Just remembered I am pretty sure ford use cable operated clutches, the second option above would probably be less hassle i.e. mating ford box to rover bellhousing
 
Our V8 is transformed. As well as fitting the new gearbox mounts I also drained all I could from the gearbox, put a new filter in & re-fitted the sump with a new gasket. Took her round the block & the difference in ride is superb. I need to get her on the motorway for a real test though I'm quietly confident of a smooth progress. I'll re-drain the 'box after 500 miles & put more fresh ATF in as you can only get approx' 2 1/2 litres of fluid out by dropping the sump. You can't drain the torque converter & thats where most of the fluid resides. Gearbox capacity is actually 7 1/2 litres so you can only dilute the old fluid with the new. Still! It's worth doing as there was a bit of sludge in the bottom of the sump & around the swarf magnet & the fluid had a brown tinge to it. I imagine it's never been changed so getting as much new ATF as possible in with the new filter must be an improvement. :)
 
He ho! (sidmouth folk week begins today)

Has anyone succeeded in replacing the P6 gear box with
a ford sierra 5 speed?
Can someone please compile the low down, ideally with
pictures?

Would much appreciate a detailed text on
"how-to install a ford sierra 5-speed gear box in a Rover P6 2200"

Wouldn't you?
Bandito :;):
 
Not that I'm aware of !, although the twin-cam M/T series has a removeable adaptor plate, so would be simple to make one for any gearbox.
 
RWD boxes definately feel better than wrong wheel drive boxes...........With the exception of Merc's!! But who would buy one of them with a manual box anyway? :p

I think that the type 9 Five speed is an excellent box, and they have always coped with the abuse I have thrown at them. My friends turbo technic's Capri used to blow them to pieces though! So I think that it's fair to say a V8 would do the same.But remember, the type 9 is just a modified Cortina 4 speed box, which was excellent.
The only glitches I have found with type 9's are first gear is a little low, and leaves a big gap before second, and they can be fussy over prop shaft alignment. Get this wrong and the gearbox will sound horrible in 4th.

Sorry..... Don't like that twin cam 8 valve Sierra engine! Give me a Pinto any day, or a Zetec! Sierra Cosworth engine has too much hype........ It's just a 16 valve pinto!! :laugh:
 
Just a thought chaps,

If any of you want to have a look at a Sierra 5 speed box, I currently have one out a car, in my spares pile. I'm located in Chesterfield, NE Derbyshire.
Just thought it might help if someone is seriously contemplating going down this route. :D
 
It's a type 9. I think that this one came from a pinto powered Capri Laser. I haven't ever looked into going the MT75 route with the old Escorts, as I seem to remember that the MT75 is a much bulkier gearbox, although probably lighter. The one benefit the MT75 does have though is synchromesh on reverse!
 
MT75 was a gearbox adopted for Ford use. designed not by ford! fairly tough but unsure its input shaft is Ok for rover outputs ? spline and diameter etc
 
lol sorry didn't check thread date. oh well .son also pointed out the LT77 is a fairly standard land rover box and wondered if it was high enough geared for a P6 anyway ?
 
You must log in or register to reply here.
Back
Top