Diff help please

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S14michael
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Re: Diff help please

Postby S14michael » Thu May 15, 2014 5:24 pm

I have measured between backplates and its about 53" soo whats the verdict wilky ?

Wilky
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Re: Diff help please

Postby Wilky » Thu May 15, 2014 8:40 pm

S14michael wrote:I have measured between backplates and its about 53" soo whats the verdict wilky ?


It'll be 52" axle which is good news for you mate as it's the most common size Atlas. Now what you have to decide is which ratio is best, the higher the number the faster the acceleration and less top end:

3.09 standard 2.8i capri
3.22 3.0 mk1 Capri, very rare
3.44 2.0 Capri
3.75 1.6 Capri

There are 4.1, 4.6, 5.1 etc etc, leave them for the rally boys though!

Haven't you got a V8 or something? A 3.09 will be the easiest to find as it's what's fitted with the LSD in a 2.8i Special. The way that you want the car to perform with whatever engine you have will be the deciding factor. For example I was thinking of putting a 3.44 crown wheel and pinion into my 2.8 as I wanted better acceleration and I'm not bothered about top speed. 3.75s are very sought after for fast road cars, especially the 2.0 Pinto/redtop/Zetec Escorts & Capris.

Price wise, the cheapest option is find a 2.8i LSD axle and bolt it on - not sure what needs to be done to fit to a Cortina, can't see it needing much. You'll be taking some risks about condition of the bearing etc. The other option is find and LSD on its own or with an axle (2.8 axles have wider brakes) and get it reconditioned with new bearings and fit the ratio of your choice. I can help you with whatever you want to do

Hope this helps you decide, if not you'll know a bit more now I'm sure!

coyb1878
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Re: Diff help please

Postby coyb1878 » Thu May 15, 2014 8:55 pm

Out of interest Wily, since I know nothing about this stuff... changing the ratio from one to another, do you like gain 0.5s on the 0-60 and loose 5mph on the top speed for example or am I wide of the mark. Would be interesting to know how it works in that respect.
Thanks

coyb1878
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Re: Diff help please

Postby coyb1878 » Thu May 15, 2014 8:55 pm

And I called you Wily.. sorry dude!

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Hot_Protein
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Re: Diff help please

Postby Hot_Protein » Thu May 15, 2014 9:40 pm

What's involved in Volvo Axle swap? Any complications with prop, handbrake/brakes?


Well you might have to have it shortened or lengthened can't remember which. The subject was covered in PPC magazine with their Saab powered Mk2 Escort project. Turned out to be cheaper to modify a Volvo LSD axle than buy a Ford equivalent. I can try and dig out the info if you like.

Wilky
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Re: Diff help please

Postby Wilky » Thu May 15, 2014 10:16 pm

coyb1878 wrote:Out of interest Wily, since I know nothing about this stuff... changing the ratio from one to another, do you like gain 0.5s on the 0-60 and loose 5mph on the top speed for example or am I wide of the mark. Would be interesting to know how it works in that respect.
Thanks


No you're about right, there's a calculation on it which I'll find. As a start, the 3.09 etc refers to 1 turn of the propshaft equals 3.09 turns of the wheels

Wilky
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Re: Diff help please

Postby Wilky » Thu May 15, 2014 10:23 pm

Wilky wrote:
coyb1878 wrote:Out of interest Wily, since I know nothing about this stuff... changing the ratio from one to another, do you like gain 0.5s on the 0-60 and loose 5mph on the top speed for example or am I wide of the mark. Would be interesting to know how it works in that respect.
Thanks


No you're about right, there's a calculation on it which I'll find. As a start, the 3.09 etc refers to 1 turn of the propshaft equals 3.09 turns of the wheels



There's about 10mph top end difference between 3.09 to 3.44 for example

stevemarl
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Re: Diff help please

Postby stevemarl » Thu May 15, 2014 10:31 pm

[quote="Wilky
1 turn of the propshaft equals 3.09 turns of the wheels[/quote]

Other way round...

S14michael
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Re: Diff help please

Postby S14michael » Thu May 15, 2014 10:47 pm

Thanks wilky thats some great info, it has a 302 V8 but with a C6 3 speed which means the top end wont be that high i would think, i havent topped it out yet. So id rather go for a highier ratio but it might be harder to get hold of.

So i think i will hunt for a capri 2.8 special axle and if it doesnt have the right internals i can source that too.

Apart from this forum where else could i be looking for a axle ?

I have been searching on ebay.

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Hot_Protein
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Re: Diff help please

Postby Hot_Protein » Thu May 15, 2014 11:22 pm

Volvo 240 Axle of type 1310 is 1390mm, 50mm shorter than an Atlas. It has a 3.54 or 3.91 ratio compared to 3.09 of the Atlas. 34mm half shaft width (6mm wider). It's 15kg heavier but does have disc brakes and some have LSDs. Apparently you can pick them up quite cheap. I read that you can get an LSD equipped axle for £200. However that was 2008.

http://www.fordcapriforum.com/forum/viewtopic.php?f=13&t=40046

http://skogenracing.editboard.com/t7007-strong-rear-axle

http://people.physics.anu.edu.au/~amh110/Diff_LSD/diff_lsd_volvo_dana.htm

Wilky
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Re: Diff help please

Postby Wilky » Fri May 16, 2014 5:15 am

stevemarl wrote:[quote="Wilky
1 turn of the propshaft equals 3.09 turns of the wheels


Other way round...[/quote]

Y[size=100][/size]

Oops, yes my mistake....it was a very long day!!

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Re: Diff help please

Postby Wilky » Fri May 16, 2014 5:28 am

S14michael wrote:Thanks wilky thats some great info, it has a 302 V8 but with a C6 3 speed which means the top end wont be that high i would think, i havent topped it out yet. So id rather go for a highier ratio but it might be harder to get hold of.

So i think i will hunt for a capri 2.8 special axle and if it doesnt have the right internals i can source that too.

Apart from this forum where else could i be looking for a axle ?

I have been searching on ebay.


I can get you any of the combinations you want plus supply them in a reconditioned axle

It's unlikely that you'll find a 2.8 axle with different internals. There is one on eBay at the minute that is a 2.8 axle with a 3.75 ratio which the seller thinks he's going to get £1500 for!!!!..I should know what's in it because I supplied it to someone in Sheffield last year and this seller bought it last week in error as he doesn't know what he's doing (wanted a 50" Atlas)

Price wise, a second hand 2.8 LSD axle is £500-£600, a 3.75 crown wheel and pinion can fetch £120 (3.44s are about £80) and then a bearing kit is £80 plus a specialist to fit it all and set it up right will be anywhere from £125-400 (yes that much variance on labour costs!)

If you let me know what ratio you want and whether you want powdercoated casing, 2.8 brakes on the axle plus your location, I'll price up to supply you with a complete, reconditioned axle

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Hot_Protein
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Re: Diff help please

Postby Hot_Protein » Fri May 16, 2014 7:00 am


S14michael
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Re: Diff help please

Postby S14michael » Fri May 16, 2014 6:28 pm

Hot_Protein thanks for suggesting the volvo axle idea, it is a hot rod but im stick with ford parts at the moment just makes it easy!

Ok wilky, so if wanted a re-con capri 2.8i special axle, 3.44 new bearings all complete but no brakes how much do you think ?

I live in high wycombe bucks.

Wilky
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Re: Diff help please

Postby Wilky » Fri May 16, 2014 6:57 pm

S14michael wrote:Hot_Protein thanks for suggesting the volvo axle idea, it is a hot rod but im stick with ford parts at the moment just makes it easy!

Ok wilky, so if wanted a re-con capri 2.8i special axle, 3.44 new bearings all complete but no brakes how much do you think ?

I live in high wycombe bucks.


PM sent

coyb1878
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Re: Diff help please

Postby coyb1878 » Fri May 16, 2014 7:00 pm

Thanks for the info Wilky

Wilky
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Re: Diff help please

Postby Wilky » Fri May 16, 2014 7:29 pm

coyb1878 wrote:Thanks for the info Wilky


No probs, it's what this and other forums should be about - helping each other, nobody knows everything!!

S14michael
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Re: Diff help please

Postby S14michael » Fri May 16, 2014 10:33 pm

theres a 3.0 axle of ebay, looks like it could go cheap, worth bidding ?

or this 2.0 one ?

http://www.ebay.co.uk/itm/Ford-Capri-2- ... 4d1d54b0f8

Wilky
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Re: Diff help please

Postby Wilky » Sat May 17, 2014 6:13 am

S14michael wrote:theres a 3.0 axle of ebay, looks like it could go cheap, worth bidding ?

or this 2.0 one ?

http://www.ebay.co.uk/itm/Ford-Capri-2- ... 4d1d54b0f8


They're not LSD axles, you'll have to find a ZF or Quaife LSD unit (around £500 second hand) plus bearings and fitting etc. one forum member was quoted £375+ vat just to refurb his standard axle

S14michael
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Re: Diff help please

Postby S14michael » Sat May 17, 2014 11:07 am

Oh right i wont bother with them then, ill just send you a message back now.