New KAAZ LSD diff into Dave H's Westfield Pt1

['The Gaffer']

Over the last couple of weekends I have been giving Dave H a hand fitting a new KAAZ LSD diff - replacing his standard Subaru diff. And replacing the propshaft in his Blue Westie.

The main reasons for the change are stronger LSD and a different diff ratio.

Before we began..



As usual with kit cars, not everything is not going quite to plan but progress is being made.

First we drained the pit in the garage, which had filled with water over the winter. We found a poor little drowned mouse in there covered in oil too. What a way to go.



Next we jacked up the car and supported the rear on axle stands and proceed to remove the wheels, hubs, and drive shafts. The latter being a real pain as the circlips that secure them into the diff decided not to play ball. A bit of head scratching and brainstorming and an hour later, they were out.







Removal of the diff then began in earnest but because the Subaru diff is not a standard fit in the Westfield, access to the securing nuts and bolts were very awkward and Dave, not satisfied with a few knuckle raps, decided a broken finger would be more in keeping with the removal. Like true men we battled on though and a few more cuts and bruises later and with the rear casing removed, the diff and prop were finally out.







A quick look inside the old diff, everything looked good..



Here's the new diff waiting to go in..



Now the re-fit.

In with the new prop..



After another struggle, the new diff and drive shafts are in too..



Then, typically two problems came to light.
1. The bottom of the gearstick fouled on the now larger prop and despite some engenious re-fabrication attempts we sadly rendered the gearstick almost useless with a two week wait for a new one.



2. One drive shaft appeared almost solid on the diff end joint, so out it came again to reveal a previous botch job (carried out by someone else) had failed causing a spring and hand made plate to rattle about inside the shaft casing. A new spring assy has just been fabricated by Nigel at Chards of Feeder Road.

Another update and more pics comming soon.

Stay tuned.

[peetee]

Great write up Phil, and that's a nice shiny new diff Dave!

[David H]

Thanks for all your help Phil, much appreciated indeed. One night we didn't realise how cold it had been until our teeth were chattering away. Must not forgot its winter in an unheated garage!!

Still, the saga is far from over as I learn a how to strip scooby driveshafts and make modifications to the factory fit to get them to work properly with ford hubs. Nigel at Chards has been a great help, his fabricating skills being far better than mine. Dont want it falling apart at 140mph!!

The gear lever situation is a bit of a mare. O well, you win some and you loose some. The trouble is, this car is so far from a normal Westfield. I genuinely don't think I've attacked anything on it without having to create bespoke solutions. I'm getting quite used to looking at something and thinking 'O I'll have to make something or get something made to cope with that..' rather than going to a catalogue and buying something.  As its so different I cant even call up another Westy owner for a solution as this seems to be the only one running this combination of kit.

I mean, how often do you hear 'Kaaz' being associated with Sevens or similar ilk?. Kaaz are better known in the drift world.
Still, once the mods are done I should have longer legs as I found myself running into the red in top when I had my slicks on (slightly smaller diameter). If I go to the Ring or another fast track this season I want to be able to go a touch faster where its possible. Changing the ratio from 4.1 to 3.9 is a step back for sprinters and hill climbers generally but I reckon I may get less gear changes going on and with a really long first, its a blast. off the mark. I prefer it personally.

Anyway, I'll have to wait and see, its a plate diff, quite full on, should be fun.

[Krazyken]

Ooooohhhhhh David!!!!

It all sounds good but please spare a thought for us mortals who want to view something other than the exhaust pipe and your car rapidly disappearing towards the horizon. 

Great work mate look forward to seeing it out on track.

[Daley Down Under]

Guess what you had for Christmas?

[David H]

Santa was grateful when he finally dropped it off, it aint light.

[Daley Down Under]

Even bigger diet required now then.  Cant wait for the warmer weather (and more importantly track day season) to arrive to try out all the new toys

[peetee]

Here here! Beginning to think my diff may well need changing too?

[Daley Down Under]

At least with 7" sierra you've got easy options (3.38 is not too difficult to find).  Cant remember it is LSD?

[David H]

I have a 3.9 7 inch Sierra LSD that has just been rebuilt.
I also have a 3.6 non LSD but the LSD can be changed over.

Both are for sale when I can be bothered to do anything about it.

Santa is still hangin around dude!!!

[Hairy Santa]

well done the 2 of you

that is one hell of a job you took on there, congrats

did you have the new diff set up for the weight of your car ? or are they non adjustable


oh ye please stop using my name in vane, thankyou  - he he

[peetee]

Yep, 7" 3.62 Sierra LSD currently fitted. Thinking 3.38 or lower to give better top end? Thoughts?

['The Gaffer']

Yep, 7" 3.62 Sierra LSD currently fitted. Thinking 3.38 or lower to give better top end? Thoughts?

You will lose some of that BEC acceleration with a 3.38, also a lot depends on tyre diameter - a small change there makes a lot of difference.

If you feel you will 'limiter out' then changing ratios might be an idea. I had a 3.62 on mine and it seemed the best of both worlds considering it spent more time on the road than on track.

All in all, a very personal thing combined with intended use and power of engine.

At least with 7" sierra you've got easy options (3.38 is not too difficult to find).  Cant remember it is LSD?

3.38 did not come as LSD but I beleive could be converted using parts from an LSD.

[David H]

well done the 2 of you

that is one hell of a job you took on there, congrats

did you have the new diff set up for the weight of your car ? or are they non adjustable


oh ye please stop using my name in vane, thankyou  - he he

not weighted, who knows how it will be? It just so happened that it came with a diff I wanted for the ratio.

Yep, 7" 3.62 Sierra LSD currently fitted. Thinking 3.38 or lower to give better top end? Thoughts?

Whats your top speed at the mo?

[peetee]

Reckon I'm getting 110-115 at 10000-10500rpm?

[David H]

yeah, i'd probably want a few more. Is that redline on yours?

[peetee]

No, max power for that engine quoted at 11,000, red line at 11,500, so just being careful. Think I'll see how it is and go from there?

[Daley Down Under]

With the 3.1 freelander LSD in the megablade, 110-115mph equated to 11000rpm but that was on 205/60/13's.   That combo was just about ok at Combe approaching Avon Rise - with a bit more power I would've run out of top speed so 3.62 might be a bit short.  Good plan to try it first though.

PS: rolling circumference of 195/50/15's is almost exactly the same as the 205/60/13's.

[peetee]

Cheers Bruv, sounds like it may just be ok? Need to get out on track first!

[RobC]

someone has been busy...! 

hey dude!

[David H]

Cheers Bruv, sounds like it may just be ok? Need to get out on track first!

Yeah try it first.

[David H]

someone has been busy...! 

hey dude!

Yo Rob!!!!!!!!!!

hows it hangin dude!!!! Getting ready for a new season!!!

[RobC]

nearly there... trying to work out front springs at the mo...

new gearbox and diff in though

All good...

[David H]

what did you choose?

[RobC]

what springs or gearbox and diff...?

Tranx GB and gripper diff also lightened flywheel

As for springs no idea at the mo...

[David H]

ratio GB?

is the diff new and if so what angle did you choose?

[RobC]

2.3 first so should give me some help to keep up this year... Diff is brand spanking.went for 30/60 in the end... after taking advice... cost me way way too much and budget is way beyond blown but... should be awesome

Most people had been trying to get me to stick an ATB in there but SP components plus other taked me round...

i know there is a very good argument for an ATB but for well over a grand I wasn't comvinced that the money and advantage was worth it.. I might be end up being wrong, but..... I think going mega hardcore first it the better way to go.

Plus now I know you've gone down the same route, I feel some what better that there is another on the same ship as me 

[Richard]

PS: rolling circumference of 195/50/15's is almost exactly the same as the 205/60/13's.

0.03% difference use http://www.alloywheels.com/tyrecalc.asp posted elsewhere I think on here as well.

There are gear / diff ratio calculators linked on this site as well to see the theoretical change effects.

One fiddly job to do there gents, very impressive. Come across props fouling short shifts on BM's before so not overly surprised you hit that little problem.

In doing this did you gather much info on the mix of diffs / half shafts / props that work in combination ? if so well worth sharing the research data. Or was it a good old get one and hope tactic ?

[David H]

Diff turned out to be wrong ratio. Cant believe it. Its the same as my old one.

Found another 3.9 so building the best out of the two. The viscous diff is going to be stiffened up to help matters.

It's never a simple job.

More to come.

Rob, is the Gripper a plate diff?

[RobC]

  oh yes 

[Daley Down Under]

That looks like a Phil Jones label

[RobC]

  eagle eyes 

once it's all finished/season starts I'll start a build thread of my own....

[Daley Down Under]

He's a bit of a whizz with Ford diffs isn't he?

[David H]

Phil Jones has my diff as we speak!!

He's gonna put some of that tasty duck oil in it. at £1,500 per half a litre or there abouts, it wants to be good stuff.

Sorry Rob, The duck stuff is no good for a plate diff.

Your diff looks lurvley

[RobC]

fingers crossed yes he has done a very very neat job on mine... was almost a shame to fit it...

already dirty with CV grease 

that's not the only nice shiney parts to be installed this winter

[Daley Down Under]

1st track day is going to be a belter - all the new cars and shiny bits.  Engine goes back into the Marlboro Car tomorrow.  Engine bay has been fully cleaned!!!  So unlike me - must be catching the disease

[RobC]

sure is, i've got to run in the diff before my first event Combe 26th March...

[Daley Down Under]

Cant do 26th - aiming to do 11th March at Combe with MSE instead.  Also thinking about 18th Feb at Oulton with BaT

[RobC]

26th's a Sprint event... aiming to beat last years time.

Dave are you just going back to a viscous then...? would you not see better times with the plated over the viscous...?

[David H]

1st track day is going to be a belter - all the new cars and shiny bits.  Engine goes back into the Marlboro Car tomorrow.  Engine bay has been fully cleaned!!!  So unlike me - must be catching the disease

What disease?