MGB rear axle V8 and non V8?

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v8trev
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MGB rear axle V8 and non V8?

Post by v8trev »

Will a rear axle from an 1800cc MGB cope with the power from a Rover V8 ?

(I realise the ratios are different)

Thanks for your thoughts :)



kiwicar
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Post by kiwicar »

Over to you I think Perry!
Mike
poppet valves rule!

mgbv8
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Re: MGB rear axle V8 and non V8?

Post by mgbv8 »

v8trev wrote:Will a rear axle from an 1800cc MGB cope with the power from a Rover V8 ?

(I realise the ratios are different)

Thanks for your thoughts :)

Yep!

As long as its the later Salisbury axle and not a banjo diff. If the diff has a rear cover plate then its the right one :)
The only difference between the 1800 axle and the V8 axle is the CW&P ratio. Everything else is the same. I've been using 1800 shafts in mine for years now.
You cant swap the CW&P to covert to V8 ratio on an 1800 axle without some machine work.

I actually prefer secondhand 1800 half shafts as the are well too heavy for anything an 1800 can chuck at it. So 30 year old shafts are well seasoned for V8 use.

If you fancy doing the conversion to V8 spec it will be cheaper to spend 500 notes on a converted axle from MGB Hive as an outright purchase. A V8 CW&P set will set you back around 400 notes and you then have to spend out on accurate machining of the diff cage to get it all to fit.

Stock V8 ratio is 3.07:1 and the normal 1800 is 3.9:1.

So if you have a 5 speed manual gearbox you will be fine for most things. But 1st gear will be hardly needed unless you want to pop wheelies :)

Perry Stephenson

MGB GT + Rover V8

9.62 @ 137.37mph

Now looking for 8 seconds with a SBC engine

http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw



https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw

v8trev
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Post by v8trev »

That's exactly what I wanted to hear !!

Thanks gentlemen

:)

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Re: MGB rear axle V8 and non V8?

Post by lolo »

mgbv8 wrote:
v8trev wrote:Will a rear axle from an 1800cc MGB cope with the power from a Rover V8 ?

(I realise the ratios are different)

Thanks for your thoughts :)

Yep!

As long as its the later Salisbury axle and not a banjo diff. If the diff has a rear cover plate then its the right one :)
The only difference between the 1800 axle and the V8 axle is the CW&P ratio. Everything else is the same. I've been using 1800 shafts in mine for years now.
You cant swap the CW&P to covert to V8 ratio on an 1800 axle without some machine work.

I actually prefer secondhand 1800 half shafts as the are well too heavy for anything an 1800 can chuck at it. So 30 year old shafts are well seasoned for V8 use.

If you fancy doing the conversion to V8 spec it will be cheaper to spend 500 notes on a converted axle from MGB Hive as an outright purchase. A V8 CW&P set will set you back around 400 notes and you then have to spend out on accurate machining of the diff cage to get it all to fit.

Stock V8 ratio is 3.07:1 and the normal 1800 is 3.9:1.

So if you have a 5 speed manual gearbox you will be fine for most things. But 1st gear will be hardly needed unless you want to pop wheelies :)
Hi there so now i have a good answer for my xjs rear axle swap i will use the 2,88 diff, like this i could use the first lol

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truckdoctor
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Re: MGB rear axle V8 and non V8?

Post by truckdoctor »

mgbv8 wrote:
v8trev wrote:Will a rear axle from an 1800cc MGB cope with the power from a Rover V8 ?

(I realise the ratios are different)

Thanks for your thoughts :)

Yep!

As long as its the later Salisbury axle and not a banjo diff. If the diff has a rear cover plate then its the right one :)
The only difference between the 1800 axle and the V8 axle is the CW&P ratio. Everything else is the same. I've been using 1800 shafts in mine for years now.
You cant swap the CW&P to covert to V8 ratio on an 1800 axle without some machine work.

I actually prefer secondhand 1800 half shafts as the are well too heavy for anything an 1800 can chuck at it. So 30 year old shafts are well seasoned for V8 use.

If you fancy doing the conversion to V8 spec it will be cheaper to spend 500 notes on a converted axle from MGB Hive as an outright purchase. A V8 CW&P set will set you back around 400 notes and you then have to spend out on accurate machining of the diff cage to get it all to fit.

Stock V8 ratio is 3.07:1 and the normal 1800 is 3.9:1.

So if you have a 5 speed manual gearbox you will be fine for most things. But 1st gear will be hardly needed unless you want to pop wheelies :)

Does this mean that the 2.8;1 ratio CWP from an xjs v12 will then fit this modified axle from MGB Hive? That is a nut and bolt change over and shim up ?
And what width from whell mounting to wheel mountingfaces.
Thanks Steve

Devonrod
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Re: MGB rear axle V8 and non V8?

Post by Devonrod »

v8trev wrote:Will a rear axle from an 1800cc MGB cope with the power from a Rover V8 ?

(I realise the ratios are different)

Thanks for your thoughts :)
Mine didnt !-------

Image

mgbv8
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Re: MGB rear axle V8 and non V8?

Post by mgbv8 »

truckdoctor wrote:
mgbv8 wrote:
v8trev wrote:Will a rear axle from an 1800cc MGB cope with the power from a Rover V8 ?

(I realise the ratios are different)

Thanks for your thoughts :)

Yep!

As long as its the later Salisbury axle and not a banjo diff. If the diff has a rear cover plate then its the right one :)
The only difference between the 1800 axle and the V8 axle is the CW&P ratio. Everything else is the same. I've been using 1800 shafts in mine for years now.
You cant swap the CW&P to covert to V8 ratio on an 1800 axle without some machine work.

I actually prefer secondhand 1800 half shafts as the are well too heavy for anything an 1800 can chuck at it. So 30 year old shafts are well seasoned for V8 use.

If you fancy doing the conversion to V8 spec it will be cheaper to spend 500 notes on a converted axle from MGB Hive as an outright purchase. A V8 CW&P set will set you back around 400 notes and you then have to spend out on accurate machining of the diff cage to get it all to fit.

Stock V8 ratio is 3.07:1 and the normal 1800 is 3.9:1.

So if you have a 5 speed manual gearbox you will be fine for most things. But 1st gear will be hardly needed unless you want to pop wheelies :)

Does this mean that the 2.8;1 ratio CWP from an xjs v12 will then fit this modified axle from MGB Hive? That is a nut and bolt change over and shim up ?
And what width from whell mounting to wheel mountingfaces.
Thanks Steve



The Jag V12 axle is a Salisbury??
If they used the same axle casing I want a 2.8:1 gear set :)

The modified MGB axle is a stock 1800 axle with a V8 pinion gear fitted, and the diff cage mounting face for the crown wheel machined back about 5mm to accomodate the thicker gars. All the other stuff is the same.

My shafts let go when I upped the torque to 450 ft/lbs. So I fitted new Moser shafts. Now hitting around the 550 ft/lb mark and all good.

I'll be interested in talking about this Jag diff Steve. If I could drop my final drive back to 2.8 and take my rear tyres up from 29" to 30" tall I reckon that would be a big help for me ??

Perry

Perry Stephenson

MGB GT + Rover V8

9.62 @ 137.37mph

Now looking for 8 seconds with a SBC engine

http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw



https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw

MikeFrost
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Re: MGB rear axle V8 and non V8?

Post by MikeFrost »

Hi,

Just found this thread as I'm about to do a V8 conversion to my MGB. V8 axles are out of stock everywhere and cost a lot more these days. Am I ok to run the standard B axle ratio? Only for road use, so will the final drive mean it's screaming it's sphericals off to get up to 70mph or will it be ok?

Devonrod
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Re: MGB rear axle V8 and non V8?

Post by Devonrod »

MikeFrost wrote:
Mon Sep 07, 2020 12:21 pm
Hi,

Just found this thread as I'm about to do a V8 conversion to my MGB. V8 axles are out of stock everywhere and cost a lot more these days. Am I ok to run the standard B axle ratio? Only for road use, so will the final drive mean it's screaming it's sphericals off to get up to 70mph or will it be ok?
Depends what gearbox you use and what ratios, even with a LT77 it should not be too bad, this is a good forum ask on here- https://www.mgexp.com/forum/mg-engine-swaps-forum.40/

FarriersV8
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Re: MGB rear axle V8 and non V8?

Post by FarriersV8 »

I have recently bought a 1968 MGB with a V8 conversion but the dif is still standard 3.97:1. From previous comments it seems that I just need to change the crownwheel and pinion. Talking to suppliers they recommend specialists to reset the gears in the dif housing. What is the best plan, just a bit worried about preloads and correct meshing.
Thanks Michael

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