Alfasud / 33 suspension conversions.

[88liam]

Front control arms?? my sud racer appears to have been modified
with alfa 33 front suspension, the car is at the tuners for set up,
and the feed back is the castor angle is 2 degrees out towards the rear of
the car, what is the diferance between the alfasud and 33 set ups and
which bits are required to solve the castor angle issue.

Liam

[bert308]

Sud has longer longitudinal arms. I found when I mounted a complete series 3 33 suspension, the wheels sat too far forward in the arches, about 2 cm so I had to use the Sud arms and still have Sud castor, which indeed seems to should be around zero while the 33 has 2 degrees. That is why a Sud steers better!

[Veesix75]

Same experience as Bert, 33 suspension on a sud means the wheel is further forward, which equals more castor angle, which I was always told helped high speed stability.

So more castor can be a good thing on a racer ?

I've always used the complete 33 suspension as is on Sud's.

[rsfruitbat]

i use all Sud suspension on my S1 33.

what impact would this have?

rsfruitbat

[bert308]

S3 33 has 2480mm wheelbase, Suds 2455mm, I think all due to the front suspension. Not sure, but I thought the S1 33 still has 2455. I also think less castor is better for a racer, more sensitive steering.

[88liam]

Thanks alot guys,

Got to the bottom of the problem, the front arms measured 580mm from
bolt hole to bolt hole, (sud front arms 580), the 33 arms measure 555 hole to hole,
it appears who ever originally assembled the suspension mixed up the parts,
Thanks to John at just suds for clarifying dimensions, i then spent an hour
removing parts from my 20ft container and found a complete 33 front
set up with poly bushes i forgot i had, result, delivered the parts to the garage
tasked with setting the car up, 2hrs later receive a phone call, the front sub frame
bolts arent long enough, not sure wether or not its a 16v cross member or a 8v,
the cross memebr on the car could also be from a sud, the sud cross member staying for now,
hopefully the car will now be ready for a test day at Oulton Park Saturday.

Would like to mention how helpfull Adie Hawkins was, i contacted him regards
purchasing his tubular bottom arm set up, which depending on how the car handles
is still a possible option, he recommended 10mm positive castor for racing, to much
can result in bump steer.

Next question is the anti roll bar, with or without, what are the negatives and
what are the positives , all feed back very much appreciated.

Liam

[Veesix75]

Well as ever depends on preferred driving style, overall suspension set up etc.

I have standard 33 suspension, just koni inserts, and have never used a front ARB on any of my racers, and was advised not to use one in my particular case. I'm sure a different specialist might advise the opposite.

However if you have modified suspension that might be different again.

Google suspension setup, while it won't answer the question in your specific case, it helps consider the different aspects it provides. Back to caster, more can provoke understeer, less can provoke oversteer......in general that is, depends on shocks, springs etc.

[88liam]

Thanks for all input guys,

Suspension sorted, sud now running neutral castor,
Gutted, more problems!! tuners checked the compression on the suds cylinders
prior to running on the rollers, one cylinder down on compression,
awaiting the results of a leakage test, no test day for the sud tomorrow.,
got over it now, the 33 is on the trailer, looking forward to taking it
out, 160bhp with a lsd and ap front brakes,

Liam