ALFAGTV6.COM

[SydneyJules]

Saw this, and have been asking myself questions

http://www.banks-europa.co.uk/cars/running_gear.htm

Could something similar be used to ditch the De Dion, and end up with out board brakes? Obviously, the shock mounting would have to be a bit different, and maybe some work with the half shafts to get it all happening correctly...

Coupled with a Colotti Straight Cut, it starts to open up some real options for the Twin Turbo guys, and as it is, could make a bit of difference to the car's abilities on bumpy roads...

Ideas?

I briefly Remember Ben Bishop talking about the New Corvette having a rear mounted, transverse leaf spring -sprung T56 with a diff off the output shaft... any ideas there?

[Mats]

I don't get it, the de-Dion is the best part of the chassis on the 116 cars, talk about stable on bumpy roads (Drive a BMW and get back to me) and very predictable.

Outboard brakes is easy enough to do if you really want it.

[SydneyJules]

Yeah I know...

But modern technology and manufacturers cant be wrong...
Surely the IRS is gonna have to offer some advantages over the De Dion-

Yeah the rear wheels are always parallel, but we're talking about thirty year old technology here...

And as far as that setup looks, its pretty damn nice!

[Daniel]

And having the rear wheels parallel isn't always a good thing.
On a bumpy road (us Ausies know bumpy roads ) when one rear goes into bump, the other has a sudden camber angle change to match. Add to that a 2.5L 8000rpm screamer at full noise and traction is suddenly and unexpectedly a problem - right Jules ?

[SydneyJules]

Thanks Daniel, I couldnt have said it better!

My car jumps around like a nervous bitch on heat some times....

And I guess subliminally I just dont give my car the berries all the time for that reason... and there are more serious Alfettas I know driving public roads too...

I just also wonder why people are so looking forward to sorting the front, ditching torsion bars, etc... but not the rear- we already have CVs at the rear, the only thing missing is the actual arms...

I for one would love to see the DeDion to IRS conversion mentioned by Kevin (or Andrew B?) in another post.... sound fcuking great-

Then there's the idea of having a mini 575 Maranello- a big six up front, box up the back, and modern suspension...

And hey, if the thing is shit, there's plenty of DeDions going around so it would be reasonably straight forward to restore the car to a tried and true method....

Why not?

Give us your thoughts mats!!!

[Daniel]

Dedion is great on a glass smooth track but then again, you need to pre-bend some camber into it. Ant the watts link points, aren't they around the wrong way - outer mounts should be on the dedion and the centre mount should be on the body ? That way the C of G would remain in the same position relative to the roll centre no matter if the suspension was in bump, droop or roll.
A good IRS (not struts, try double wishbones) should well outperform our poor heavy dedion on the rough public roads and probably on the track as well.
So Jules, how much is it going to cost me to convert over to IRS

[sh0rtlife]

the thought of a shrunken jag rear under an alfa..mmm mmm mm..but likely to wide..perhaps a merkur? or 80s t-bird irs setup?...course im of the school of scavange and re-use whatever you can....still i too have looked at the car and thought..all this other factory race-ish stuff and to go so far as to give it a tranaxle with IRS ability only to mount it technicaly to a straight axle...its like they were thinking IRS and the budget guy slaped em in the face and the cut the IRS budget out

[SydneyJules]

yeah shortlife, a Porsche guys asked me what happened there once too!

"It's like they went to all the trooble of having IRS.... and chickened out!"

We could go completely custom and start welding stuff to the diff/box and end up with a PROPER Ferrari style GT....

The other idea (aside from custom making, or getting the above Banks-Europa setup modified to suit) would be to get hold of a skyline IRS setup, and shorten it's width to fit... the track difference isn't huge, but I think you may be able to cradle it under the transaxle, and strengthen/brace the shock towers to take the load.

Then you could also possibly shorten the Skyline Halfshafts, because they are much stronger than the Alfa ones....

Daniel... when I know how much it costs I'll let you know!!

I dont think it would come to heaps heaps...a skyline rear end disc to disc is about $400, and Silvia rear end (4 bolt, not 5) is as little as $200...

Makes sense!

[Mats]

Well, if you ladies are looking for a smooth ride you might be right. Also, for jungle driving there might be some features that makes IRS beneficial.

We men who don't do dirtracing would lower the roll centre and "adjust" the camber/toe. If you are really going for it you can do the reversed Watt as described above or even Panhard (we're not jungle driving, remember?). Spend the time (and money) to make the front end work with the rear and the car will be plenty fast.

[Micke]

There's a homologated IRS for the 116
Very innovative.
Worth the effort? For smooth track - hell NO!
If I had endless resources - YEPA!

[Zamani]

Micke,

The red 75 IMSA at the Museo Storico, does that have IRS? I don't have complete photos of the rear underside, but it isn't a regular dedion like ours.

Hey waita minute, you, the guy from Volvo-land, weren't you there at the museum a while back? Was that a highly modified dedion or an IRS?

[Micke]

Z'man,

it's pretty exactly 20 years since i've been there. My RAM has gone truly random and I can't remember no more.

[Maurizio]

There were pictures of a imsa being restored a few years ago on the net.
I think it was located somewhere in England.
The dion was cleverly converted into an irs, without giving up te stock look. Looked like they wanted to fool the tech inspection.
I will have to search my home pc for the pics.

[Mats]

Yes, I was there -02, Yes I gotz the pics, No its not IRS.

On the other hand, don't assume that everything on that car was done to maximize speed, a lot of stupid rules often prevent that.

The Rear Suspension on the "IMSA" in the Museo Storico has a de-Dion setup with adjustable camber. It has a raised watts pivot point and outboard brakes.

[Greg Gordon]

The DeDion set up seems pretty good to me. A lack of stability on rough roads is usually caused by a bad bushing at the forward DeDion tube. Put a SZ bearing up there with poly bushings in the Watts linkage and it will be rock steady under all conditions. A little bit of negative camber will help cornering, however that's largely due to tire deformation under cornering loads and not a problem related to the DeDion tube design.

Could an irs set up be an improvement? Sure it could. However the Alfa's DeDion setup is better than almost all the factory irs setups out there. I own three irs cars and they all suck compared to the DeDion setup.

Greg Gordon,
www.hiperformancestore.com