Page 37 of 38

Re: There may be trouble ahead

PostPosted: Sat Jul 27, 2019 6:34 pm
by Colin
I've just spent an enjoyable couple of hours reading through the epic journey of this car's brilliant restoration and build. So much highly skilled and dedicated work over the last five years.

I've learnt a lot by reading this epic (sorry, Viva) thread. Highly recommend others take the time to read the journey!

Continuing good luck with it Bill. Don't give up! :D

Re: There may be trouble ahead

PostPosted: Fri Aug 02, 2019 5:58 pm
by rizzo
Thanks for your input Colin much appreciated, no don't worry i've no intention of not finishing the build, ive come this far :D

When i'm not at the paint shop stripping the paint i still tinker on a few bits back home, so just finished the reverse light.

Re: There may be trouble ahead

PostPosted: Fri Aug 02, 2019 6:41 pm
by rizzo
I've also been looking and making the axle bars, decided to go for round upper and lower as i think they look a bit better, after much thought i made the upper with round bar, more so because the extra room wouldn't go a miss when the exhaust is fitted.


Yes i know they do look abit on the small size but these are only marginally smaller than a Toyota Amazon which probably comes in at 2 ton.

Re: There may be trouble ahead

PostPosted: Fri Aug 02, 2019 6:48 pm
by rizzo
The likely hood is that i probably wont bother to post alot more from here on in, once its painted its all about putting it back together again, which has been covered already. :D

Re: There may be trouble ahead

PostPosted: Sat Aug 03, 2019 12:28 pm
by 1972nail
There are differing opinions on using a channel section or tubes for the rear suspension bottom arms. I personally adhere to the view that DTV engineers and the original Vauxhall designers had and prefer a light channel section.

The way the rear suspension is designed to work when cornering the rear bottom arms need to twist and the channel section allows this to happen.

Preventing the twist, by fitting box or solid section, only transfers the twisting load to the bushes and suspension mounts and these resist the loads far more than the channel section arms originally would do. The effect of this is similar to fitting a really thick and stiff anti roll bar to the rear suspension. When you consider that the first mod you do to a standard Magnum is to ditch the rear anti roll bar, adding extra roll stiffness to the rear obviously isn't a great idea.

Vauxhall used channel sections for a reason. The DTV engineers did recognised the failings of the Vauxhall design and boxed in the area around the bushes to prevent the construction in that area from splitting apart under extreme competition conditions, they didn't box in the whole arm because they were aware of the need to allow it to twist.

DTV works Magnum rear suspension showing modified rear bottom arms.

On the Chevette HSR the DTV gurus swapped the standard round tube bottom arms for standard Viva bottom arms with ends boxed in, to reduce the rear end roll stiffness.

I know that there are many people who defend the decision to use box section or in your case tube bottom arms but my opinion is that if Vauxhall and DTV preferred light channel section arms with stiff bushes for the reasons outlined above then that's my preference too.

Re: There may be trouble ahead

PostPosted: Sun Aug 04, 2019 8:07 am
by lord13
^^^Ditto^^^

the standard tarmac viva set up was 'soft at the back, hard at the front' this was to enable light precise steering and good adhesion for getting the power down.

Re: There may be trouble ahead

PostPosted: Sun Aug 04, 2019 10:19 am
by 1972nail
True, but when talking soft at the rear we are discussing spring rates. The tortional resistance of thr lower rear arms influence the roll resistance of the rear suspension and not the ability to squat and transfer weight to the rear wheels to aid traction. A stiffer rear anti roll bar or stiffer lower arms will increase understeer without increasing the spring rates.

Re: There may be trouble ahead

PostPosted: Sun Aug 04, 2019 7:25 pm
by rizzo
I did think that this might come up for discussion which if fair enough and its good of you to put the information down for all to see, but to be honest i'm happy with the decision ive made, there is a large amount of Vivas out there already that have solids fitted thanks to one supplier and so far as i know very little feedback to suggest its a bad idea, along with my old V8 HB that had solid bars which was abused quite abit with no issues.

Re: There may be trouble ahead

PostPosted: Sun Aug 04, 2019 9:23 pm
by 1972nail
As I said, there are differing opinions and so long as you're happy and as you already have experience of solid arms then you have an informed view on the subject. It's always worth sharing the various ideas for discussion for others to take on board and decide for themselves.

Re: There may be trouble ahead

PostPosted: Wed Aug 14, 2019 9:33 pm
by glenn93
what are you doing to strip the paint ?