Javascript Disabled Detected

You currently have javascript disabled. Several functions may not work. Please re-enable javascript to access full functionality.

exact differences from standard to RTS front end

Started by _355 EH_ , Apr 10 2010 02:44 AM

Next

Please log in to reply

30 replies to this topic

#1 _355 EH_

Guests

Posted 10 April 2010 - 02:44 AM

i know the top wishbone mounting points are lower on the LX RTS front end are there any other differences ?

Back to top

#2 dattoman

Do I feel lucky? Well, do ya, punk?

Administrators
16,485 posts

Name:Neil
Location:Perth Western Australia
Car:LX SS , 76 Cadillac , 3 x dattos
Joined: 04-February 07

Posted 10 April 2010 - 03:49 AM

Did ya read these?

http://www.gmh-toran...showtopic=14102

http://www.gmh-toran...showtopic=29860

http://www.gmh-toran...=1

Back to top

#3 _cruiza_

Guests

Posted 10 April 2010 - 07:42 AM

Yes there are exact differences and I have a vague idea as to what they are.
Steer rack mounting
steering rack ratio
steering arms
top wishbones different shape
lower wishbone, some say made from thinner steel
spring rate
shock rates
Sway bar size and fitment

Back to top

#4 yel327

Oh My, Don't you post alot

Members
13,565 posts

Joined: 10-February 08

Posted 10 April 2010 - 08:35 AM

Don't forget there are 2 x LX RTS front ends. Normal and A9X. Both are very different.

Back to top

#5 _cruiza_

Guests

Posted 10 April 2010 - 09:17 AM

Ok if your going to be exact about.
Phase 1 LX normal front end with sway bars
Phase 2 UC Torana with all the changes
Phase 3 LX A9X as Phase 2 but with different steering arms, rack mounting and rack ratio, and stub axles and brakes

Back to top

#6 yel327

Oh My, Don't you post alot

Members
13,565 posts

Joined: 10-February 08

Posted 10 April 2010 - 09:52 AM

The point I was making was although Paul is correct that the upper arm mounting points are lower for the first of the LX RTS, the second type (or phase 2) introduced with A9X doesn't have it's arms lower, in fact from memory they are higher than early LX?

Back to top

#7 _cruiza_

Guests

Posted 10 April 2010 - 03:19 PM

The point I was making was although Paul is correct that the upper arm mounting points are lower for the first of the LX RTS, the second type (or phase 2) introduced with A9X doesn't have it's arms lower, in fact from memory they are higher than early LX?

I wasnt bagging you, sorry if it came across that way, the only genuine A9X that I have had a good look at was 79 Brock bathurst car and the upper arms on that are 27mm down from the top

Back to top

#8 dattoman

Do I feel lucky? Well, do ya, punk?

Administrators
16,485 posts

Name:Neil
Location:Perth Western Australia
Car:LX SS , 76 Cadillac , 3 x dattos
Joined: 04-February 07

Posted 10 April 2010 - 04:12 PM

I wouldn't use a racecar as an example of a genuine A9X
They were a supplied bodyshell and the teams threw what parts they had at them

Many say the A9X has UC upper arms
I've seen enough of them to say that most don't
So there seems to be conjecture on all the front ends
My SS supposedly has a UC front... the holes are in the same spot as my NON RTS LH

Back to top

#9 _cruiza_

Guests

Posted 10 April 2010 - 04:26 PM

I agree totally with you there hence I said which car it was that I had looked at, I was told at the time that the teams expermented with different hieghts for the top wishbone mounting point as different wheel sizes made a difference as to what hieght was best. That said John Shepperd, and Harry Firth both say that while they pushed the rules as far as they could, they never cheated and under the rules of the time you weren't allowed to move suspension pickup points

Back to top

#10 dattoman

Do I feel lucky? Well, do ya, punk?

Administrators
16,485 posts

Name:Neil
Location:Perth Western Australia
Car:LX SS , 76 Cadillac , 3 x dattos
Joined: 04-February 07

Posted 10 April 2010 - 04:37 PM

Weren't allowed to add parts either
But plenty of cars had panhard rods

Back to top

#11 76lxhatch

That was easy!

Members
7,195 posts

Location:Unzud
Car:SS
Joined: 04-August 08

View Garage

Posted 10 April 2010 - 04:40 PM

My SS supposedly has a UC front... the holes are in the same spot as my NON RTS LH

Yeah? Pretty sure that's not right, must have the LH/early LX cross member with UC arms

Back to top

#12 yel327

Oh My, Don't you post alot

Members
13,565 posts

Joined: 10-February 08

Posted 10 April 2010 - 06:31 PM

The UC front ends had the holes up really high. When you look closely at LH/LX, LX RTS and UC side by side you cannot even drill the holes for UC height arms into LX RTS crossmember as they are different right at the top. The LH front end is the same as UC at the top but the UC holes are higher again (from memory). I remember when I built my LX hatch many years ago I couldn't get a good UC crossmember, so I modified an early LH one the same and had to drill the upper holes above the original LH ones to make it the same as UC. Not sure if A9X had the holes up as high as UC or not, but they definitely used the same/similar upper arms to UC as far as I know. Every one i've seen has had UC style upper arms.

Back to top

#13 Collo

( . Y . )

Members
114,647 posts

Location:Newcastle...Home of me.
Car:A Black POS
Joined: 29-February 08

Posted 10 April 2010 - 06:43 PM

So what effect (if any) would UC arms on an LH crossmember be?

Back to top

#14 _cruiza_

Guests

Posted 10 April 2010 - 06:58 PM

Yes A9X had UC style upper arms
the top ball joint is mounted further back giving more caster, I cann't remmber but I think the lenght was about the same from LX to UC, what it does is stop the wheels form rolling under while cornering the sway bars limited the roll as well and the dirent steering arms were for the different arc that the wheel now moved in, and yes I am being a little general and rough in what I am saying but the idea was to improve the cars handling to be more precise and less understeery, The difference coming from Holdens General Manager changing from American to Hanbegur (spelling) a German who liked cars to handle

Back to top

#15 dattoman

Do I feel lucky? Well, do ya, punk?

Administrators
16,485 posts

Name:Neil
Location:Perth Western Australia
Car:LX SS , 76 Cadillac , 3 x dattos
Joined: 04-February 07

Posted 10 April 2010 - 08:07 PM

Does this look offset ?

Posted Image

Back to top

#16 _cruiza_

Guests

Posted 10 April 2010 - 09:19 PM

It does to me but then it could be camera angle the top ball joint is to the rear of the center point of of where it mounts to the subframe i.e. where the top nut of the shock is, so to me looks like a UC top arm, but camera angle could make it look that way

Back to top

#17 yel327

Oh My, Don't you post alot

Members
13,565 posts

Joined: 10-February 08

Posted 10 April 2010 - 09:38 PM

I agree with Michael. The principal difference between RTS geometry and pre RTS geometry is the top balljoint being moved backwards by about an inch or so. From about 6/76 this was introduced to HX (but the RTS package didn't arrive till HZ), and also in A9X. In the W sized vehicles it was achieved by moving the whole upper control arm backwards (just compare a HQ or HJ upper mount by looking where the shocky sits, then look at a HZ or WB). In The U sized vehicles (Torana and Sunbird) it was done by moving the balljoint within the constraints of the control arm. The early RTS in Sunbird and later Torana was done a little differently, but it must have been done on a budget and I think everyone would agree that an A9X and UC out handles any previous LH/LX!!

It may be just my eyes, but Datto that upper arm looks to be bolted where a "phase 1" LX RTS arm sits.

Back to top

#18 _ohhgeee_

Guests

Posted 11 April 2013 - 12:43 PM

sorry i know this is an old thread but does anybody have a photo of something in particular that i can easily identify what front end i have??
atm its all pulled apart, my cars an lh but as we know that doesnt really mean much when parts are interchangeable in a car thats not far off 40yo with a handfull of keen owners in the past.
ive been reading and reading threads but still not 100% sure.
its important because ive just ordered the hamburger kit and they need to know which one to send me.
someone please help

Back to top

#19 lx308

Lotsa Posts!

Members
2,841 posts

Name:Tony
Location:Australind
Car:Nuffin. Goin touring.
Joined: 25-March 07

Posted 11 April 2013 - 01:00 PM

Have a look here. It might help.
http://ls2lxhatch.com/suspension.htm

Back to top

#20 TerrA LX

Fulcrum Fixture

Members
14,241 posts

Location:Sid 'n' knee
Joined: 31-May 06

Posted 11 April 2013 - 02:20 PM

My 4/76 has factory sway bars front and rear, it handled better than any UC I've driven.

Back to top

#21 _ohhgeee_

Guests

Posted 12 April 2013 - 11:36 AM

Have a look here. It might help.
http://ls2lxhatch.com/suspension.htm

thanks alot that clears things up abit

Back to top

#22 Dr Terry

Technical + Numbers Guru + Moderator

Moderators
3,315 posts

Location:Eastwood (Sydney) NSW
Joined: 13-November 05

Posted 12 April 2013 - 02:27 PM

My 4/76 has factory sway bars front and rear, it handled better than any UC I've driven.

That's a little strange, the first factory rear sway bar on Toranas didn't appear until the intro of RTS (11/76 Sunbird & 3/77 for 6/V8 models).

Also, prior to those dates they didn't get a front bar unless it was an SL/R or SS. Anybody of course can just bolt a front one on.

Dr Terry

Back to top

#23 TerrA LX

Fulcrum Fixture

Members
14,241 posts

Location:Sid 'n' knee
Joined: 31-May 06

Posted 12 April 2013 - 02:56 PM

That's a little strange, the first factory rear sway bar on Toranas didn't appear until the intro of RTS (11/76 Sunbird & 3/77 for 6/V8 models).

Also, prior to those dates they didn't get a front bar unless it was an SL/R or SS. Anybody of course can just bolt a front one on.

Dr Terry

Aren't those two sentences contradictory? Edit; maybe I am just reading it wrong.
What I think you mean is that prior to RTS only LX models to get factory sway bars were the SL/R and the SS?

FWIW mine is SS. the rear bar bolts to the rear outer trailing arms.

Edited by TerrA LX, 12 April 2013 - 02:59 PM.

Back to top

#24 _cruiza_

Guests

Posted 12 April 2013 - 04:14 PM

My June 76 hatch had factory swaybars front and back, but then when you are talking a 30+ year old car who knows f someone got factory bars and bolted them on latter Mine was a SL Hatch too

Edited by cruiza, 12 April 2013 - 04:14 PM.