aussiemart

Hi,, im looking at building an xe or xd for improved production circuit racing and was just wondering if anyone would know witch model would be more suited.

I know xe,s have watts linkage rear end but ive also heard that on the limit the std setup can be hard to drive without major mods witch arnt alowed in this class anyway

Also is it possible to get a flare kit like the phase 5 and the dick johnson turbo six has anywhere,, this would help if i could widen the track.

car will have 550 horse alloy headed clevo tremec five speed detroit locker

Thanks for any help Aussie Mart

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aussiemart

Okay guys i tried in the suspension and general threads but NO answer to my question ,im real sorry to ask this here but i think this would be the best place to try since youve all got or have had an xd or xe.

I was building an xw circuit race car but have now decided to build an xd or xe for improved production circuit racing so i can give it to some of these commondore drivers with the idea that they are cheaper to replace and should in theary handle better than the xw, wider track and all.

My question is witch one would you guys recomend xd or xe,, ive heard that an xe can be hard to drive on the limit or when you have lots of grip say with slicks, well dick johnson had lots of trouble anyway, but i have read this elswere aswell.

The problem seems to be the watts linkage rear end witch seems to be desighned backwards.

has anyone driven an xd and xe in anger, and what seems to be the difference

Thanks soo mutch for any responses to this,, im trying to make a choice asap so i can start hunting for a decent shell

Cheers Aussie mart,,, Watch out holden boys ive lit the wick.

__________________
Feed my will to feel this moment urging me to cross the line..
We'll ride the spiral to the end and may just go where no one's been...
M.J.Keenan

s_pak

Aussiemart, I have no idea personally but why don't you email DJR and ask the legend himself, he'd know!

Where do you plan to race the car?

Ahhh...to go back in time to the True Blue/Greens Tuf era...

aussiemart

Hi S-pak,Email dick, Thanks thats not a bad idea at all,, i plan on racing at all the victorian tracks and the odd mallalar, oran park, wakefeild park and they do have one race at BATHURST

As you said its a bit like the old days,, im a bit surprised that the grids are full of toranas commodors datsuns mazdas but not one early falcon,, xd xe seemed a good choice,, widest track of any falcon and very cheap to by and replace if the worst was to happen.

rules are quite free with the only problem bieng that you must run 60% aspect ratio tyres,,, but i can use my alloy headed clevo tko tremec full floating nine inch diff,, only front race seats are required , brakes are free and hopfully i can get this under 1400 kg,,, dicki did with full interior cast headed clevo.

Thanks for the response s-pak ill give him an email today
cheers AM

__________________
Feed my will to feel this moment urging me to cross the line..
We'll ride the spiral to the end and may just go where no one's been...
M.J.Keenan

xbgs351

XD & XE are far lighter and a dime a dozen.

The problem with the xe rear end relates to the difference in length between the upper and lower arms. The lower arm is long, and the upper is very short. This results in roll steer etc as the short upper arm pulls the wheel forward as it follows its arc.

Do you have to use standard suspension pickup points? If not you should be able to make a suitable set of upper arms. Have a look at the HQ's that race in Appendix J and you will see what I mean.

Also chat to the Appendix J mustang and falcon racers. They are full of knowledge and are happy to share it as long as you don't ask ANY stupid questions.

The front end needs a lot of work. You need to get more negative camber gain by relocating the upper arm. When relocating the upper arm you can also lessen the bind in the lower arm inner bush that you get from running a lot of + castor. Bump steer requires attention.

Phase 5 body kits should still be available.

Wouldn't use a detroit locker, instead use a Gold Trak.
http://www.stockcarproducts.com/rear9c1.htm

aussiemart

Thanks so mutch for the reply xbgs mutch apreciated,, Unfourtunatly you have to use the standard pickup points So i may have to go with an xd and fabricate a watts linkage setup and lower arms.

I had been looking into those gold track diffs awhile back thanks for reminding me,,the last time i drove my xw at calder it rained and the detroit was lots of fun,,NOT.

I think you can run a strut front end and retain the lower control arm from what i read into the regs so i might take a look at the rrs kit(http://www.rrs-online.com.au/html/products.htm),,,has bigger brakes as well,,, if not the top arm relocation sounds good.

would like to use a front spoiler and rear wing since there allowed,, may not need the flares since the largest rims allowed are 8inch wide anyway

Also would it be hard to put xe panels on an xd?

Thanks alot Aussie Mart

__________________
Feed my will to feel this moment urging me to cross the line..
We'll ride the spiral to the end and may just go where no one's been...
M.J.Keenan

xbgs351

If you go the xe option you would have to copy dick johnsons xe setup. "Australian Musclecar" issue 10 has some info. The original arms were retained with soft sponge like rubber. The lower arm was duplicated with auxilary arms that ran right next to the original arm. They also added a third top arm that ran from the diff centre forward. This additional arm which due to the rules was no longer than the others. As it was in the centre it eliminated the roll steer. The car also ran a chasis mounted watts linkage.


Most of the historic touring cars use them. They also use tilton clutches.$$$$

I'm skeptical about this setup until it is proven. A substandard Mcpherson setup such as on Mustangs leave a lot to be desired. Questions to ask include:
Castor - how is it achieved? Does it bind the lower arm inner bush?
Camber - being Mcpherson you will need a LOT.
Bumpsteer
Scrub radius
Camber gain
Ackerman
SAI

See:

http://corner-carvers.com/forums/sho...&highlight=rrs

Brakes are not much bigger. ie 286mm cf 300mm. Are brakes regulations free? Race brakes are not a fan of the Holden VT brake setup, and that was googd enough for me.

Did you know the phase 3 falcons came with two sets of holes for the upper arm?
Most of the XE group C's are XD's.

What tyres are you allowed to run? Slicks or something like Hoosier Street TD?

Steffo

For Improved Production Racing you have to run Yokohama A032R. Regular street tyres. A032R is the IPRA regulation tyre. I'm thinking of running IPRA myself with some sort of Falcon, but I need to find a detail set of the rules so I can build a car accordingly.

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aussiemart

Thx guys,,,heres the rules if you whant a read (
(http://www.ipravic.com.au/)link on this page under(About IP Racing & Membership info)

I have that issue of aussie muscle cars and also the early issue with the xd
,,the xe issue has some good pics of the rear end so that should be helpfull
, and he still uses the std front suspension with some mods.

Good reading on that link you posted xbgs the front strut system does sound good but some more owner feed back would be nice too,, im pretty sure that caster camber is adjusted the same way as std,, it stilll uses the std lower control arm and caster bar but with the strut i guess you dont have the serious camber change with roll- bump as with the std setup and as reported there a negative camber increase during roll.

i do like the idea of easy ride hieght adjustment.
But i whant rule out std wishbones and relocate them yet it may be a good start.

as steff said the the control tyre is the yoky a032r and im pretty sure id have to run a 225 60 15 all round i dont think they make a 16 inch tyre in that width from what ive found or a larger 15,,,this makes brake sizes limited too:-(( but ive had great succsess with my xw and std front brakes beleive it or not,, with the right aprouch to brake prep i was outbraking brembo shod 911s somehow:-)) too the surprise of the owners.

so with a slightly larger disc and alloy calipers i think it should be better again,, they are only 5-8 lap races and i had no probs with 20 laps before.

So may have to stick with 15by 8 inch rims.

Thx guys Aussie mart

__________________
Feed my will to feel this moment urging me to cross the line..
We'll ride the spiral to the end and may just go where no one's been...
M.J.Keenan

xbgs351

225/50R15 is as wide as the AO32R's go, so you will be using 15 x 8" rims.

You may wish to widen the rear track, although I doubt flares will be required.

XD rear end with a Panhard Rod or Watts linkage would be far easier than the XE route.

The mcpherson strut will have less negative camber gain than a relocated uca. This works in favor of the short arm, long arm setup. Just look at how much more static camber the v8 Supercar commodores had to run in comparison to the the falcons.

If the castor for the Mcpheson strut is adjusted the same way as the factory setup, than the Mcpherson holds no advantages here.

I would be trying to get as much weight out of the car as possible.

I have been told that the VT PBR calipers have a serious flex issue. I also doubt that you can get good pad for them.

Engine capacity is free? Stroker?