Ford Forums banner

1 - 20 of 24 Posts

·
Banned
Joined
·
2,631 Posts
Discussion Starter #1
honestly, this is what i want to do. i want superior grip and only irs will give me that.

last time i checked, it would cost something like $3K to source the parts from ford, and possibly even more.

has anyone done anything like this? ideally, i'd like to find a wrecker with a totalled au xr8 and rip the irs out of it, get a stronger diff and put in new shocks/springs.

i mean, if anyone has any info, please, do let me know. i'm just trying to see whether this would be feasible or not. and cost is a factor too. i don't want to spend $55000 building a car i could have bought off the showroom floor for $50000. it would be stupid, realy...
 

·
Registered
Joined
·
3,023 Posts
Ive looked into this too, but I have discovered that the Falcon platform aft of the axle is different in IRS vehicles. It has more mounting points to accomodated the extra links of the IRS.

Im not sure if the mounting points can be created on a non-IRS platform but as saying goes, 'with enough money anything is possible' ;)
 

·
T5 Expert Operator
Joined
·
6,540 Posts
Just a sueggestion,

I reckon it's not worth the time and effort to convert your AU into IRS. With $1200 i reckon you can get the car to handle very very nicely.

But if you are really keen, what budget is your limit? Take into account apart from the $3k for parts labour cost would be another thing.
 

·
Banned
Joined
·
2,631 Posts
Discussion Starter #4
oh shyte!

i was under the impression that it was a matter of ripping out the axle and the adjoining components and shoving the irs in there... bugger... :(

*shakes head*

i don't know anymore... it will cost me too much to build a car that i want! i mean, i might as well sell Baby and buy a new TE50 when they are released!

GRRR!! frustrating!
 

·
Copyright �2003
Joined
·
1,517 Posts
If setup right, the live axle is still good as long as the road is fairly flat. :cool:
 

·
NSW TICKFORD OWNERS CLUB
Joined
·
324 Posts
I didnt realise till the other day when i read closer the actual specs of V8 Supercars that Falcon and Commodore in race form both use a rear 'live axle'. Is this for weight reasons, obviously IRS would be 'better' but weigh more plus I suppose on a race track there aint pot holes and broken surfaces etc. where IRS benefits most...just something i didnt realise...
 

·
Two SC 61's = trouble
Joined
·
6,360 Posts
How long do you think an i.r.s would last with 600+ h.p going through it? Yea good idea if G.M couldn't us the 9" and had to use there own..Not just diff, but suspension,as you said not too many pot holes..N.V.H doesn't come into the equation on a race car...
 

·
Australian BA XR6 Falcon
Joined
·
1,249 Posts
dkmaj said:
I didnt realise till the other day when i read closer the actual specs of V8 Supercars that Falcon and Commodore in race form both use a rear 'live axle'. Is this for weight reasons, obviously IRS would be 'better' but weigh more plus I suppose on a race track there aint pot holes and broken surfaces etc. where IRS benefits most...just something i didnt realise...
Its a simple matter of keeping the cost down.
IRS would probably be of benefit on the circuit to a certain degree, hitting those curbes for instance.

Kieron
 

·
Australian BA XR6 Falcon
Joined
·
1,249 Posts
ebxr8240 said:
How long do you think an i.r.s would last with 600+ h.p going through it? Yea good idea if G.M couldn't us the 9" and had to use there own..Not just diff, but suspension,as you said not too many pot holes..N.V.H doesn't come into the equation on a race car...
Don't forget those Cossie Sierras with IRS pumped out this sort of power, mind you they did eventually use a DJR developed 9" diff centre, which happens to be the forerunner to the diff centre used by all of todays V8 Supercars :D

Kieron
 

·
Banned
Joined
·
2,631 Posts
Discussion Starter #10
grunter

that's my main issue! i drive fairly briskly and i'm all over the place on sydney roads...

i've given up on this though. i'll probably get some ok wheels and swaybars and leave it at that. i want a TE50 or an AV xr8. no point in spending money on this car... it'll do me for the time being.
 

·
Two SC 61's = trouble
Joined
·
6,360 Posts
Kieron said:


Don't forget those Cossie Sierras with IRS pumped out this sort of power, mind you they did eventually use a DJR developed 9" diff centre, which happens to be the forerunner to the diff centre used by all of todays V8 Supercars :D

Kieron
It would cost heaps to enginer the system strong /light enough.Dick did have a few probs with bent/broken back end.Remember the big loose he had on conrod straight with his set up,about the only time he looked like he was scared.Couldn,t jump curbs with them.

I would say the cars now are harder on suspention components than with Falcon being heavier,wider tyres,curb jumping.For big car they are a lot faster too..
Those diff's have been around for years,the old days of group c used 9". I think they are putting approx 100 h.p more now.
Then there's all those things like roll steer,camber change,roll centres etc etc.Mind you same with solid axle..
Notice the camber they have on them? Looks like they have a fair bit of toe in as well.I guess so can excellerate early in corner & tyre wear??
 

·
Australian BA XR6 Falcon
Joined
·
1,249 Posts
ebxr8240 said:

It would cost heaps to enginer the system strong /light enough.Dick did have a few probs with bent/broken back end.Remember the big loose he had on conrod straight with his set up,about the only time he looked like he was scared.Couldn,t jump curbs with them.

I would say the cars now are harder on suspention components than with Falcon being heavier,wider tyres,curb jumping.For big car they are a lot faster too..
Those diff's have been around for years,the old days of group c used 9". I think they are putting approx 100 h.p more now.
Then there's all those things like roll steer,camber change,roll centres etc etc.Mind you same with solid axle..
Notice the camber they have on them? Looks like they have a fair bit of toe in as well.I guess so can excellerate early in corner & tyre wear??
Dicks loose down Conrod was caused by a flat tyre, the car then backed into the wall causing suspension damage.

The diff used by the Cossie Sierra's (and the centre used by the V8's today) arn't the Ford 9" housing, its a purpose built aluminium housing built by Harrop, the use the 9" ring gear of course, but its Richmond stuff iirc.

Certainly setting up an IRS would be harder then the solid axle. Durability/strength wise they would be fragile, but this would all be worked out fairly quickly and more than likely before they actually raced them.

Your right about the current solid axle setup, they do have camber change, I don't know about toe though and i'm also unsure about the rules regarding such adjustments, ie is rear camber free, or must they use a set camber?

Kieron
 

·
Pursuit Reincarnation Dog
Joined
·
7,777 Posts
In my time running production spec racer (VL Commo) the way to get camber and toe in the rear end was to bend the diff housing to the angle you wanted (limited by the axle bearing loads of course).

The result was noticeable, and bearing changes every couple of races sorted out the reliability. Then the rulemakers heard about this sort of thing and started checking..... (doh!)
 

·
Pursuit Reincarnation Dog
Joined
·
7,777 Posts
Oh, forgot to mention. Some of the teams run an IRS diff housing mounted in a sheetmetal fabricated "live axle". The axles run dry like in IRS and there are adjustments built into the axle housing to change axle angles etc.

Don't know if it has changed since my last look though....
 

·
Registered
Joined
·
1,112 Posts
I remember Steve Winwood getting nailed when he ran an AU XR8 with the live axle in it. The body shell he used apparently had both mounts for the IRS and the live axle. At least that's what his navigator told me at the time.
 

·
In a blue Galaxy
Joined
·
5,716 Posts
Couldnt you just change a few stuff on the live rear? panard rods and radius arms can help not only accelerating off line but stableising the car round corners.
As for the V8 supercars I know that they use IRS at the back with watts linkage and at the front they use independant upper and lower wishbones.
 

·
In a blue Galaxy
Joined
·
5,716 Posts
well thats the Fords anyway. Im not sure what holden use im presuming mcpherson strut?
 

·
Australian BA XR6 Falcon
Joined
·
1,249 Posts
Cobra said:
Couldnt you just change a few stuff on the live rear? panard rods and radius arms can help not only accelerating off line but stableising the car round corners.
As for the V8 supercars I know that they use IRS at the back with watts linkage and at the front they use independant upper and lower wishbones.
I hope you just made a typo their Cobra :p the V8's use a solid axle with trailing arms and the Watts link at the rear. At the front the Falcons use the double wishbone and Commodores use the McPherson strut - originally designed at Ford too:D

Kieron
 

·
In a blue Galaxy
Joined
·
5,716 Posts
where do you get this from Keiron? I was always under the impression that the Ford V8 supercars used independant upper and lower wishbones with penske coilover dampers with eibach springs.
 

·
In a blue Galaxy
Joined
·
5,716 Posts
at the front I forgot to add. at the rear i thought it was a 4 link trailing arm with watts linkage? I dunno ay.
 
1 - 20 of 24 Posts
Top