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General >> Give/Need advice to/from others >> Diff Swap ?
(Message started by: Tons_of_fun on Oct 16th, 2007, 1:03am)

Title: Diff Swap ?
Post by Tons_of_fun on Oct 16th, 2007, 1:03am
Hi all,i,ve been reading with intrest that some cossie owners have swapped there diffs for a 2.0l version & was wondering if the same could be done for a 12v? The reason being is that i,ve rescently driven a couple of cossies & love the acceleration,but am loathed to sell my 12v after all the work i,ve put in to make it a trophy winner.I,ve always loved the cologne engine for it,s simplicity but regarded the gearing as being a bit too tall.Do you think a new diff would be a viable option?Is it likley to make a significant improvement to the acceleration without making it a screamer on the motorway ?(5-700 rpm increase @ 70 is an acceptable trade off in my opinion).Advice/Opinions gratefully recieved.Thanks...Craig :)

Title: Re: Diff Swap ?
Post by Highlander on Oct 16th, 2007, 1:24am
Yep just the same diff on the 12v as the 24v (3.64)

the 2.0 16v has the 4.27 diff, the 8v has a 4.09, 2.3 has a 3.91 so you have plenty choice :)

my 24v has the 4.27 so its turning 7 times instead of 6, revs higher but not unbearable on the motorway, still get 20mpg with it now compared with 25 on the stock diff but a lot quicker off the mark 0-60 around 6 secs compared with the stock 7.9 ;)

The 4.27 diff in the 12v should see it outstrip a stock 24v ;)

On what other car forum can you post a question after midnight and get and answer in 20 mins ?? ;)

Title: Re: Diff Swap ?
Post by Tons_of_fun on Oct 16th, 2007, 12:25pm
Thanks Highlander,your a star  :) :).Dead right as well,about the speed of response (we must all be insomniacs) ;D ;D,but thats the beauty of a top forum like this.lots of like minded individuals all with the same aim.To keep our scorps alive  :D.One final question though ! Am i correct in assuming i would need the 2.0l VSS to obtain the correct speedo reading? Is it simply an electrical connection or a little more involved? Thanks in advance...Craig :)

Title: Re: Diff Swap ?
Post by Highlander on Oct 16th, 2007, 5:50pm
Yep you need the vss or more exactly the little pinion with the teeth that the vss connects to, the number of teeth are different for different models/engines.

Title: Re: Diff Swap ?
Post by Tons_of_fun on Oct 17th, 2007, 12:49am
Marvelous.Think this will make a nice winter project  ;)Expect a new ad in the wanted section soon  ;D ;D ;D Huge thanks again for the advice.Much appreciated,top chap.....Craig :)

Title: Re: Diff Swap ?
Post by Highlander on Oct 17th, 2007, 7:33am
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=200162992015&ssPageName=STRK:MEWA:IT&ih=010

They dont come up that often and you may get a bargain ;)

Title: Re: Diff Swap ?
Post by Tons_of_fun on Oct 17th, 2007, 2:56pm
Thanks for the heads up Highlander.My local scrappie has 3 x 16v in at the moment,he,s checking for a 2.0l as we speak.Only trouble is he hasnt a clue what the vss is/looks like & to be honest neither do i  :o.Just got to sweet talk mother into letting me use her drive as Solihull council does not allow ANYONE to repair/service vehicles on the driveway if you have a garage. :'( :'((seriously).My garage is full of mowers /strimmers etc ,besides the car wouldnt fit anyway  ;)

Title: Re: Diff Swap ?
Post by peteHull on Oct 17th, 2007, 3:18pm
VSS a per diagram here  http://www.fordscorpio.co.uk/images/a4lde1.gif

items 58,59 and A02.010

This is the complete vss unit

hth

Just realised you live in Sillyhull I mean Solihull, I just live in ordinary Hull and our council aren't bothered... }{
Pete

Title: Re: Diff Swap ?
Post by Tons_of_fun on Oct 17th, 2007, 3:34pm
Aaahhhh yes.Now i see.Thanks for that pete.Had better call him & tell him he needs to look at the box & not in the diff for it then  ;D ;D ;D.I assume this is to give the correct speedo reading but was wondering if this is all it does.(i.e. dosent send any messages to the cruise cont etc).If this is the case can i get away without fitting it & live with a under reading speedo??? (Thinking ahead in case the vss unit isnt available,you know what scrappies are like  ;) ).As for solihull council  >:( >:(.Changed the anti freeze on the wifes car last month.Accidently spilled about a cup full on the drive.I soaked it up straight away with cat litter & disposed of it at the local recycling centre along with all other waste fluids i had,but a nosey neighbour reported the spill & i was fined £80 enviromental charge  :o >:( >:(.Believe me im just dying to catch the bin men dropping litter as they drive off .Revenge is sweet  ::) ::)

Title: Re: Diff Swap ?
Post by peteHull on Oct 17th, 2007, 4:35pm
}{ }{ }{ []

That's if you can get revenge, for all my happenings this last couple of years I would be chasing revenge into eternity.... I'd probably bang my head when I found it too... Grrrr

Vss sends signal to ecu and possibly controls other functions although I'm not all that sure how it all gels.  You need the cog on the vss to have the correct number of teef as the 2ltr diff, Stewart (Highlander) may know more info on this topic as he has done the conversion and is very knowledgeable (for a person who lives in the wilderness)   }{ sorry Stewart grin grin grovel grovel.

Anyway I'm sure you'll get it sorted there are plenty of 2ltrs about in scrapyards at the mo, but it would be betterer to get the thing working as it should.... and KEEP supporting your local council....I do :-[ :-[

hth Pete

Title: Re: Diff Swap ?
Post by harry.m1byt on Oct 18th, 2007, 7:59pm

on 10/17/07 at 15:34:12, Tons_of_fun wrote:
I assume this is to give the correct speedo reading but was wondering if this is all it does.(i.e. dosent send any messages to the cruise cont etc).


The VSS feeds its signal to the speedo, the cruise control and the ECU. All it is, is a regular pulse varying in frequency of the pulse dependant upon the vehicles speed.

So far as the cruise control is concerned it will still work, because all it does is aim to keep the frequency of the pulses regular by adjusting the throttle. One point to note is that the cruise is designed to cut out if the speed falls below a certain level (25mph I think), so this would be different along with the speedo reading.

Modern motorcycles use a similar thing (a pulse from the VSS). Many are grey imports fitted with a kph speedo. To solve this problem (kph to read mph) and to solve the problem of inaccurate speedos, a small electronic widget was designed to recalibrate the speedo which fits in the VSS pulse wire. It takes in the regular pulses at one frequency and precisely adds or subtracts a percentage from that  frequency - to produce a new output of your choice.

The above is one solution, but perhaps not as cheap as getting the correct VSS from a scrap car.
 

Title: Re: Diff Swap ?
Post by Tons_of_fun on Oct 18th, 2007, 8:14pm
Thanks harry,it,s becoming a bit clearer now  ::).I dont know !!! Whatever happened to the good old days when all you needed was a big pair of carbs & a 4 branch manifold  ;D ;D ;D

Title: Re: Diff Swap ?
Post by dan_the_man on Oct 18th, 2007, 9:16pm
could someone please give me an inication as to how many hours work it is to swap a diff ? for a trained mechanic.

Title: Re: Diff Swap ?
Post by harry.m1byt on Oct 18th, 2007, 9:22pm
If no one offers a better idea, my guess would be a couple of hours tops....

Three drive flanges to disconnect plus the diffs own fixing to the bodywork. It may take a little longer if a tow bar has to be removed and refitted.

Title: Re: Diff Swap ?
Post by dan_the_man on Oct 18th, 2007, 9:27pm
SWEEEEEET !I think I could beon the lookout for a 2.3 diff ! I do have a tow bar but my mechanic is price friendly.

Title: Re: Diff Swap ?
Post by Tons_of_fun on Oct 19th, 2007, 11:39am
Yep i would agree with that dan,NO MORE than 2-2 1/2 hours m8.The position im in at the moment with the council being petty,im going to have to use a garage but no one by me wants to take the job on.(Cant make money if I supply the diff).Oh well i,ll get there in the end  ;) ;D ;D

Title: Re: Diff Swap ?
Post by Highlander on Oct 19th, 2007, 1:02pm

on 10/18/07 at 21:27:38, dan_the_man wrote:
SWEEEEEET !I think I could beon the lookout for a 2.3 diff ! I do have a tow bar but my mechanic is price friendly.



The 2.3 diff has a 3.91 ratio,
The 24v has a 3.64
The 2.0 16v has the highest ratio of 4.27
The 2.0 8v has a 4.08

So if you are after the highest acceleration go for the 4.27

Title: Re: Diff Swap ?
Post by Highlander on Oct 19th, 2007, 1:14pm

on 10/18/07 at 21:16:59, dan_the_man wrote:
could someone please give me an inication as to how many hours work it is to swap a diff ? for a trained mechanic.


if you dont change the VSS sprocket with the teeth on it the speedo will read higher (about 15% dependant on speed) and everything on the car will work according to that reading eg cruise etc, it will work just the same, you can set it at 70 and it will stay there but you'll really only be doing 60 ;)

There can be a bit more involved depending on the types of diff you are working with.

The early diff has a single mount backplate on it, the later diffs have a double mount.
The backplates are interchangeable so no problem there (apart from getting the Torx bolts out) ;)

You will have to remove the backplate even if both your diffs have the same one fitted to remove the drive pinions (driveshafts)

The 24v has larger (wider) cv joints than the other models and larger bolts BUT the splined drive pinions are the same so the larger 24v driveshafts will fit into the 2.0 diff (and others)

Otherwise as long as you can get the car up on ramps for enough clearance and have the right tools its a doddle :)
I dont think theres anything fancy needed tool wise, torx bits to fit the cv joint bolts and diff backplate, 19mm sockets and spanners and lots of WD40!! them diff mounting bolts will take a bit of shifting, especially the long one under the front of the diff ;)
Oh and right angled cirlip pliers to remove the circlip on the inner end of the drive pinions to release them from the diff (although i used a screwdriver and a hammer) ;)

Oh and dont let it fall on your head, its heavy! ;)

Title: Re: Diff Swap ?
Post by dan_the_man on Oct 19th, 2007, 7:10pm
Highlander , your a great help and a top man . thank you.



Title: Re: Diff Swap ?
Post by howiedintheplace on Oct 21st, 2007, 7:24pm
Yeap this is the cheapest way to get your 24V to move faster & also good for towing too.

Not so good for motorway MPG but o.k round town.



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