Alfasud Track Suspension

[DavidF]

Hi all,

Just did my first Supersprint in my Alfasud TI with stock suspension and looking for a way to reduce the body roll.

Want to do a piece-meal approach and thought some stiffer springs would be a good start.

I use the car about 70% track - 30% road as I use it to drive to circuits and also do the occasional Nav Rally.  It's not a daily driver so willing to put up with a stiff ride on normal roads.

Can anyone recommend some spring rates?

Thanks,
David

[Sportscar Nut]

David

Unsure of exact spring rates except to say that even the Ti Twin Carb springs are way too soft for track work. Perhaps Beninca Motors or Vin Pace in Melbourne could assist with recommendations but beware that if you want to lower the car, this is expensive due to the McPherson struts modification required. There are a few Trofeo racers who might also provide input!

I am aware of a couple of Sud/ Sprints that have used late 1970's Cortina 6 cylinder rear springs for track work and apparently still look like factory standard when fitted!

I have done pretty much everything possible to my Sud suspension as follows (except for springs).

- Koni Yellows all round with the front shocks bump stiffened a further 25%
- Solid control arm bushes
- Re-inforced lower control arms (due to cracking after fitting the 1.7 Twin Car motor)
- Neoprophane top steering mount bushes (made big difference to improving steering directness)
- Lowered engine & sub frame (modified top engine mount and aluminium spaces for engine mount & sub frame)
- Re-inforced inner front guards
- Increased negative camber on front wheels (need to play with to balance handling versus tyre wear and try a few different settings)

Note the Koni's and lowered engine made the biggest improvement to handling - lowered engine & sub frame was learned from the Alfasud racing series in Australia in the early 80's.

Hope this helps and good luck.

Paul

[meizhak]

David,

out of interest how much did you lower engine?

cheers

Meizhak

[DavidF]

Hi Paul,

Thanks for the info, I also made contact with a few Sud racers in NSW and got similar advice with regards to the shocks so they are now on the agenda too.

The spring rates that quite a few people are using are 400lbs on the front and 200lbs on the rear.  The reinforcement of the front chassis rail with braces was also recommended with the front being stiffer and placing greater loads on the rails.

Lowering the engine sounds intriguing, however I am a bit too much of a novice for that!

Was wondering about the bushes so probably something worth doing when it is all in pieces.

David

[Sportscar Nut]

David

Thanks for the spring rates; might try a set in the Sud although is rather stiff for road use at present.

Biggest cost is the modified engine mount to lower the motor/ sub frame but makes a huge difference to handling - particularly with the top strut tower bushes providing sharper steering. Lowering the motor changes the 'tilt' on the lower control arms making them almost horizontal to the ground so assists also with smoother power delivery (ie reduces torque steer).

Meizhak, the engine in the Sud has been lowered by 38 mm's. Ie extension required on top engine mount.

Regards
Paul

[Evan Bottcher]

Hi Paul,

Interesting info, I've got a couple of questions if you don't mind? 
- Who modified the top engine mount for you? 
- "Neoprophane top steering mount bushes" - which bushes?  Do you mean at the top of the strut tower?
- Solid control arm bushes or polyurethane?

I've been told to lower the engine, but haven't ever got around to it - will put it on the list, along with reinforcing the front chassis rails, and tagging the cage properly into the windscreen pillars...

Our Sud is running a set of springs for which I have the paperwork but can't interpret it - many many numbers (pitch angle, wire length, corr stress etc.), but I think it suggests they are 200lbs front and rear (not sure - doubtful).  Shocks are koni yellows on the front, and an old set of reds on the rear.  Urethane bushes on all the control arms.  Cupla degrees negative on the front (slotted bolt holes on the front hubs).  The car is an inch or more lower than standard - no mod was required to the macpherson strut that I know of.  Sway bar unhooked on the front (need to take it off), and a sway bar on the rear.  Very uncomfortable to drive on the road, but we really only drive it to the track and back.

Next steps for the suspension I think will be:
- reinforcing the front chassis rails to stop the front of the car falling off sometime in the future
- a new set of springs - we're still limited by body roll lifting the inside front wheel in the tight corners
- bit more negative camber on the front
- add some negative camber to the rear

Very interested to hear more advice about spring rates.

cheers,
Evan.

[DavidF]

Hi Paul,

I was a bit concerned about the spring rate too, but the advice was from someone with a road going Sud too (runs koni's), apparently it bounces over the bumps rather than crashes through them and isn't too bad.

For the Koni's, I am aware there are the different types (Yellow, Red etc.) but is there a specific model number you have?

Cheers,
David

[Sportscar Nut]

Evan

Beninca's modified the engine mount back in 1997 and also had the top strut tower bushes made for me at the same time (yeah, not the steering mount bushes). Could be urethane but does not detail in the bill (yeah, also have every receipt ever spent on the car - ouch!).

The bushes in the control arms are aluminium and are annoying at present as 'groan' a lot when driving. Might try the urethane bushes; can you let me know where you got them from?

I have full details on the mod's required to lower the engine. 38mm is a guess but is close - have in my records full measurements for engine mount & alumininum blocks for sub frame & lower engine mount which I made. Will try to locate pre Spectacolo.

Take my word, lowering the engine transforms the Sud but keeps the original handling characteristics intact. I remember the smile on my face when I first drove the car post lowering the motor!

Note you are running Koni reds on the back - are they too soft considering the springs? I have been highly recommended the Cortina spring trick by two ex Sud racers (cheap too as you just ring a Ford wrecker).

Who did your springs to lower the car and what was the effect?

In terms of your camber settings, you should speak with Beninca's and hope they remember the settings from the Sud series (Joe is the person to speak to as he raced the car).

David, my experience with Koni yellows is fantastic and the car is not unsettled when 'punting' through rough corners - really confidence inspiring. My suggestion would be to just buy a set of second hand Koni's from a wrecker - I think from memory 33 Series 1 struts use the same inserts for the front but can't recall exactly. Koni's are fully rebuildable to any spec required and I think my Koni's front inserts were secondhand reds (rebuilt to Sport specs). Front & rear shocks to rebuild at Top Performance (Koni distributor) was around $500.

Unfortunately my Sud does 'crash' a bit over potholes etc at lower speeds.

Happy Boxer motoring.

Paul

[Evan Bottcher]

Thanks Paul - great info.  Will definitely be taking an even closer look at your car in November!  (I've already had a very close look, including judging it for the wash'n'shine!).

The springs were supplied by Bruno at Maranello Pur Sang a couple of years back or more.  We did them at the same time as fitting the front suspension with outboard ventilated brakes from a 33 16v.  Prior to that it was running standard springs with a coil or more cut off (previous owner).  We tightened the rear shocks and fitted the yellows on the front.  The difference it made was unbelievable - the car was completely transformed on the track.  I can't remember how many seconds it took off my times.  The 33 suspension runs a little bit longer wheelbase (the front control arms are shorter) and a bit more caster, so it's a little heavier in the steering.  Very stable at 'high' speed (sud speed).

The next step was a rear sway bar - that made a huge difference also, the back of the car is much more stable and holds the front down more.  Next time I drop the front crossmember I've got to take out the front swaybar completely (just unhooked at the moment).  Camber is a bit limited on the front because the Simmons are too wide (wrong offset?) - need to get/make some spacers.

I need to go lower and stiffer (and drop the engine as you've advised) as I pick up the inside front wheel on the really tight stuff - e.g. turn 4 at Sandown (see pic attached).

[meizhak]

Meizhak, the engine in the Sud has been lowered by 38 mm's. Ie extension required on top engine mount.

Cheers Paul,
Is the front lowered 38mm as well? this would make the crossmember bolts on my 33 about 190mm long.

Is this the case with your sud?

thankyou

meizhak

[Sportscar Nut]

Meizhak

Engne was lowered the same amount all round but need to check exact measurements (ie around 38 mm). I did need to fit longer sub frame bolts from memory - obviously around 38 mm longer!!

Evan, unfortunately not sure if will bring Sud to this years Spectacolo as have spent a fair amount of time recently detailing the 105 and can only enter both cars in past winners category (so will only bring one). You are welcome though to drop past my place to check out my 'toyshop' (given we both have fine taste in Alfa's). Interested in how your 1750 is coming along - who know's you may own an Esprit soon too! Let me know as could talk for hours about both Alfa's.

Regards
Paul

[meizhak]

Engne was lowered the same amount all round but need to check exact measurements (ie around 38 mm). I did need to fit longer sub frame bolts from memory - obviously around 38 mm longer!!

Just one more question, did you modify the mount on the body or the one that bolts to eng/gearbox.

OK so technically that was two questions. 

cheers


PS any pictures of this mount and your car

[Sportscar Nut]

Meizhak

No problems with the question as have enjoyed the Sud for over 18 years now and enjoy discussing them!

The separate top engine mount between body & engine was modified by Bennica's. Basically cut the mount at the top where it is currently welded, added 38mm and rewelded. Really neat job too as sprayed black and only a 'purist' would be able to tell (giveaway though is the ground you can see between subframe and body below the radiator).

What engine/ gearbox combo is in your 33? The 1.7 twin carb is a fantastic motor and I recently rebuilt my gearbox with 33 1.7 IE internals (for better gearing and stronger star gears/ bearings etc).

Regards
Paul

[meizhak]

PAUL,

I am currently preparing series one 33 to accept 1.7 injected 16v. Decided before I put the engine in might as well prepare the engine bay/ front end  as best as possible.

Will be welding up some cracks, bracing the front bulkhead to the chassis, probably strengthening the chassis while Im there.

Have collected alot of parts for my build, but just chassis preperation at this stage

cheers for the info

meizhak