as well, most kitcars use english axle whereas atlas is quite a bit heavier?
as well, most kitcars use english axle whereas atlas is quite a bit heavier?
re the de-dion
http://www.craig.chamberlain.name/lo...ediontext.html
also camber or toe-in can be set using shims, unlike on a live axle where you would be loading the bearings
Gary, may i suggest you pop down to dax and have a word with Peter and Gary (the other gary!) about why they prefer the di-dion in all 3 of the types of car they build, over both double wishbones and live axel. Also if you see the CCAR system you can see how it overcomes the problems you get with camber on a double wishbone setup.
I've Looked at Duncans car quite a few times, seen it go.. too many times, and seen the looks on peoples faces when he turns up at sprints
The thing is i've also seen many an Escort with different rear suspensions on them, and they just havnt performed.
The Classic has to be the much rated and expected Colin Mcrae Car, slower over the same stage with virtually identical engines .... Is Colin using the car ...????? no.
Peters CC is a wonderfull feat of engineering, and is something which is really hard to explain without the car or drawings "well this pulls this over here, and that pushes that over there ..... "
The thing that i'm trying to get across, especially when people have to pay to have this work done is in the case of an Escort, most forms have been tried and most have gone back to a 6 linked rear.
I would love to have the time.. and the customer to develope new suspension.. its what I enjoy doing, but i feel i know where it would lead.. and thats Formula Car suspension, wishbones all round.
On the subject of camber... the best cornering car of all time .. Bill Millikens " camber car"
Errr... actually it's yes Gary, he is using it to compete against his dad and his brother who are both in GP4 (Atlas rear) escorts in this years Colin McRae forest rally. Will be interesting to see how he fares against the big Mk2 brigade that will be in attendance as well as the more modern stuff.
He normally enters it as the course car but this time he's in the 2wd class in the red mk2 and apparently protests are already coming in about the 'modifications' to his car!
popcorn:
Sierra cosworth turbo race car
QMN saloon car championship
RETRO Motorsport
alister won it in a atlas axled 6 link set up,colins diff broke in testing[cossie diffpercy: ]his replacement mk1,engine failed,why have a wrc car when an old mk2 does the job
popcorn:
And from that do we draw these conclusions....
A .... Alister is better
B..... Colins car is worse
or
C if it works dont fix it .
I can't for the life of me think that the diff was a standard item.. it must surely have been the 4K(?) Msport item.
And Dave.... To finish first...first you have to finish
This setup would work very nicely under the back end of an escort.
From the limited edition S204 impreza.
Regards
Which got beaten on the Mull this year ...
S203 actually...... S204 hasnt been built yet
And it wouldnt because the Diff isnt strong enough....
The RWD Imprezas about now for Drifting etc are using complete skyline rear ends
The Scooby set up is nice but would not work well in a high power RWD application
HTH
Dom
Picture taken from the following site with some nice pictures of the s204 impreza.
http://news.hspn.com/articles/210/2/...ble/Page2.html
Even if it is not that strong, it sure looks good!!!
Tom
Anyone been keeping an eye on the guy with the 4x4 converted mk2
Thats good work, looks like it protrudes alot under the car though
I think in 2wd form that setup would be a bit heavy compared to an atlas, unless its lighter than it looks?
Sierra cosworth turbo race car
QMN saloon car championship
RETRO Motorsport
Fiat 131 Abarth rear. Worked better than the last of the works tarmac spec Escorts.
What really has changed between the rear suspension specs of those Escorts and those of today?
The Fiat still has massive camber change ... which isnt a problem on the loose, but looses out on a smooth surface
It can work well in roll as long as the inner pickups are at the right height though.. as the lower arms are getting longer on the Fiat
Ah! The Fiat was by far better on the hard stuff than the Escort! It never won on the RAC or the Safari for example. Whereas it reigned supreme on tarmac events such as Sintra,Corsica,San Remo,Antibes and Monte Carlo.
Another point,don't forget that the 131 had a live axle, coil sprung 5 link rear end as standard!.But the Abarth engineers chose to ditch that in favour of a complex independent system. Those guys had a racing pedigree with their dimunitive 850 Abarths remember.
Even Audi used a Chapman Strut rear end on their almighty Quattro.And don't forget they were starting from scratch. If a 5 linked live axle was superior,why did they not utilise one?
I did say " it can work well in roll as the lower arms are getting longer"
But as you know .. a rally isnt like a circuit, corner speeds etc and pitch etc are all different. And most people out there will be doing trackdays not rallies.
In droop you can loose rear braking as the contact patch decreases due to the + camber
In bump you can loose accel grip as the contact patch is de-creased due to - camber
In roll , as long as the geometry is worked out for a given ride height and the inner pick up points are adjustable for different ride height it can work well. Rally cars tended to roll a lot in the 70's-early 80's .. one wheel in the air etc . So the camber change can be a good thing.
Fat, if i can call you that, dont get me wrong, an IRS can be good, its just that people are thinking of putting production IRS's on different cars , Production IRS's are designed for two things .. comfort and packaging. The need 3 bums on a rear seat means Chapman strut wins over double wishbones (hence Audi's Chapman strut)
On Chapmans later cars he went to double wishbones allround
The thing that i'm trying to get across is , if your cutting up a car to fit suspension then fit the best. And at the rear of an escort that hasnt got seats etc that has to be a diff in a cradel that has mounts for double wishbones.
The Fiat engineers looked at what the car needed and designed it for that purpose ... and yes it worked ... unlike the Sierra set up which was designed for a passenger saloon not a competition car .. move a Sierra through its suspension range and the camber change is massive
Just a scrappy quick one , but this is what i would be looking at doing...
Gary have a look at the Tiger Avon kit car. The rear end is almost like that.
Hello Gary
What you are drawing is correct BUT..
I think that the droop en bump on a race car is not that much.
Correct me if i am rong.
So the camber change through bump and droop is acceptable ?
Greetz from Holland
True but unless the camber change is designed for what the chassis needs its still un-acceptable
100% correct ......... but ... spending hours and hours fitting an O/E IRS from some repmobile to a competitive car is also a no no.
I've never said dont fit IRS ... just fit something that works. Theres 400bhp cossies that get beaten by lesser powered escorts with live axles, the Sierra wasnt designed for ultimate road holding and power transfer. The BMW IRS is commonly accepted as being better, still has flaws under acceleration , but if you just want 1/4 miles times then a live axle wind hands down, but if its roadholding you want then an IRS can be better than a live axle.
All i'm trying to put across its no good fitting something from another car and hoping its going to work ...
Ages ago I stated that an Escort with a 2WD rear beam from a Sierra will handle like a Sierra ... same as a 4WD Sierra floorpan under an Escort will handle like a 4WD Sierra.
A case in point here is Grahame Fords Mk2 Cortina, up against his brothers less powerfull Anglia and the anglia left him for dust. Grahame asked why, out the back i asked him to launch the car, this was the resulting tyre marks.
Properly thought out double wishbones taking in to account the roll center, squat,toe,camber etc will beat a live axle hands down on 99% of driving.
The other thing we have to remember is 99% of the people who are reading this may, just may take their car to a trackday, where they can only go as fast into a corner as the car infront, and will probably spend more time clocking up times at Santa Pod than round Brands Hatch in a race. And if after reading this thread they fit an IRS from a sierra and run slower at the Pod then they are not going to be happy. If the majority of the owners timed events are at the dragstrip then a live axle thats linked wins hands down, easy to set up for preload and plants the tyres sqaure to the floor.
Case in point ... Ricky Hutchings car at Brighton ... BMW IRS, big rims , big engine ... didnt see his car at the top of the turbo escort times, a timed lap at a race circuit may prove the potential of the conversion far better than a drag race .... but how many people on here will be racing on a circuit ?
A double wishbone rear... using equal length arms, at the circuit add some neg camber and toe in, at the drag strip set the wheels upright (in the loaded position) even better if you can adjust some anti-squat in there too ... thats a winner in both cases.
Just to throw a spanner in, anyone thought of combining an IRS with a transaxle such as a 944 Porsche in true RS1700T styley??
The Porsche Transaxle is going to be cheaper than the Hewland and yes a transaxle is a better way to go if your doing that much work to the cars ... better weight distribution etc .
But the Hewland has the Lugs cast into it for the wishbones ... 50/50 to which is easiest/cheapest ..
second hand Hewland from an F3 along with the driveshafts and uprights and wishbones ... bellcranks etc .. the whole lot ..
dont see top fuelers running irs - so that takes care of the drag strip issue.
hi guys! sadly ive nuthing to add but what i will say is this site is mega for information!!!!!!! some of you guys are on the ball!!!!
i started this thread along time ago.since then i seen phil colins mk2 in the flesh build by quick motor sport it is a work of art and wins in ireland all the time hes proved it works colin mc rae car is to but the gearbox is the weakest link and keeps breaking.Phil colins car has extra hi turrets 4 or 5 inchs more.
and i belive its diff is a focus wrc ford is stamped on it.dose quick motor sport have a website or dose have any pictures or info or how it is build cause it really dose work (happy new year)
Not started yet. Got into drifting and my seirra has had all the time.
Fitting an mt75 in the escort first.
Hi guys quick addition by me after reading all the posts on this issue...
I had a crack at fitting the Sierra IRS, yes it works, BUT (and i expect a few of you knew this was coming!) I'm going back to a 5-link setup, purely because its far simpler and probably stronger as there is less parts!
Also I go to quite a few tarmac rallies and I also worked for JRE Motorsport for a while. Live 5/6 linked axles seem to be the proper choice for a Mk1/2 escort. They nearly always beat scoobies and the like, even if they lack the traction out of the bendy stuff.
Anyway, sierra LSD's as std are crappy viscous type which is fine for road use, but useless in a competition setting...
Damn good site info here tho! Keep it up guys!
Has any one tried the Camber compensation on the rear on an escort.
This will leave the tyres planted and 0deg during launch and camber changes during cornering?
Has anyone tried it?
Warren
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