Donor

[Guest peter2b2002]

just seen a sierra saphire 4x4 dohc, my question is does this have the same rear subframe as a standard sierra, I know they have a limited slip diff and the wrong type of gear box but is the rest OK for a 2b?

peter2b

[megadodo]

Its the same style subframe as "ordinary" Sierra's but may have a bigger diff otherwise dimensions are the same (I have one in my 2B)! I hired a twinky 4X4 one many years ago when they were new and was impressed by its handling. It felt a bit stiffer than other Sierra's I had driven but that will be down to spring and damper rates not differences in the subframe.

[Redspec]

Front hubs are no good, we got one for the zero build and it had a 7" diff. The type 9 box will fit the DOHC but needs the flywheel skimming.

 

Steve

[Guest peter2b2002]

thanks for the tips, as normal sierras are getting rather rare donors I have been looking for some thing else for my mate to use for his new toy, we are getting new front hubs/calipers any way

peter2b

[Dave Ed]

what are the possibilities of building a 4x4 robin hood.

would the geometry of the front driveshafts etc be able to fit or be re-engineered to fit a zero?

[ibrooks]

Dax have done it in their seven.

 

In a Sierra the front diff is bolted to the side of the sump and the driveshaft for the passenger wheel goes through the sump. Trying to retain this setup pushes the engine too far forwards in order to get it between the front wheels so the trick is to ditch the 4x4 sump and move the diff on it's own so....

 

you would need a longer front prop-shaft. The diff would need to be mounted in a suitable frame. The halfshaft lengths would no doubt need to be tweaked as the front track of a Ronin Hood is different to that of the Sierra (although there are other disadvantages to doing this with the 4x4 system so it might be better to alter the wishbones to make the front track match the Sierra). There is a possible issue with getting the front prop past the engine as the front diff will want to be higher in relation to the engine to keep the halfshaft angless anything like sensible.

 

The transfer box exits the gearbox on the drivers side so I suspect you would have trouble with losing the space on the drivers side of the cockipt.

 

In answer to the original question though. The rear axle is exactly the same as a standard Sierra. The diff will be a 7" LSD and is the same as the Sapphire Cosworth 4x4. They only went to 7.5 on the 2wd Cossies because then the rear diff had to handle all the power (and 9" diffs are motorsport stuff). It might or might not have rear discs. The gearbox is the MT75 with a transfer box on the back - it's relatively easy to remove the transfer and fit a 2wd rear end to the box but if you've got a 2wd MT75 to take the rear casing off you might as well use it instead. The MT75 is a lot stronger than the type-9 but it's a bit bulkier and quite a bit heavier. The engine will need a different sump and pickup pipe to be converted to 2wd format. Most of the front suspension is different in some minor fashion but as mentioned it's likely only the hubs you would need for a Hood anyway.

 

Iain