Race suspension question from a new Alfa driver

Alfa Romeo ONLY please!
Fortis621
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Race suspension question from a new Alfa driver

Post by Fortis621 » Fri Aug 12, 2005 10:17 am

I'm in the process of building a GTV6 race car and need your input on race suspension. The car was resurrected after being asleep for years. The car was stripped, roll cage fabricated, mechanical parts + engine refreshed, and the body freshly painted. I took it out last May to AROSC Buttonwillow event and it ran great. If interested, some photos of the car can be seen at http://www.fortismotorsport.com/GalleryAlfa.htm and
http://www.alfabb.com/bb/gallery/AROSC- ... w-May-2005

During the shakedown at Buttonwillow, I quickly realized that the suspension needed some serious help. What is a good suspension setup for track? What size torsion bar and sway bar combo is recommended? Where is the best place to get them? I've been reading about RSR coilover kit. Where can I find these? Also, does anyone know if Alfa Ricambi is still in business? I've tried to contact them but didn't have much luck.

I've been racing BMWs for years now. I'm totally new to the Alfa scene. I have to say, the more I learn about Alfas, the more interesting they become.

Thanks.

Colin
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aggarcia
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Post by aggarcia » Sat Aug 13, 2005 6:43 pm

What suspension depends on what rules you run under and how much you want to spend. For race parts for the GTV6/Milano the best source is Andy @ Performatek . Most of the race parts on my IT GTV6 are from him.

AG
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Post by junglejustice » Sun Aug 14, 2005 3:50 pm

If you can go coil-overs, the RSRacing race setup is FANTASTIC - the car is on the rails....

Group 2 in Seattle Washington ( www.group2inc.com ) is now a dealer and Joe stocks full sets as well as individual parts - call him - 206.378.0900...
...to Alfa, or not to Alfa? That is the question...
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Post by Zamani » Sun Aug 14, 2005 8:59 pm

Colin (Fortis),

What does your car ride on now? With just minor mods, your GTV6 can turn 1:40s at Willow Springs. It doesn't take much to make the GTV6 handle well.

I can only imagine what times your car will put down with RSR suspension and a slightly hotter engine.....

The fastest GTV6 at AROSC was an almost stock 3.0 with basic suspension mods (bigger torsion bars, konis, sway bars and shankle rear springs), 1:37+ at Willow Springs.

You have quite a few options:

RSRacing
Shankle (if you can reach them)
Performatek
Beninca (Australia)
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Mats
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Post by Mats » Mon Aug 15, 2005 2:23 am

Sounds like you got some seat time there. Great! :)
What does your rules allow you to do in the chassis department? How serious is this car (i.e. how much time/$ are you willing to spend)?

What are your goals?
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Post by Dennis » Mon Aug 15, 2005 3:53 am

Looks like a serious track car!

Like the others said; What are you allowed to run, and how much are you willing to spend?


The RS suspension kit some mentioned is a great dual duty road/track set. I have it on my own car for years now and it is still the next best thing to a full race set up and was designed to perform on the Nordschleife which is a bumpy track. Your car looks like it won't see any road, just pure track and I would advice to go a bit more extreme if you can afford to do so.

Let us know, lots of proven setups and wild ideas!
'81 GTV6 3.0 QV
'91 75 TS (track)
'02 BMW 330i Touring
Fortis621
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Post by Fortis621 » Mon Aug 15, 2005 9:14 am

At the moment, I'm not really constrained to any class rules. I'm just planning on running this car with AROSC and some open track days. I have plenty of point left in class C to do the suspension and still be okay. I just wanted to build a car that I can have some fun with. At the same time, I don't want to spend a fortune.

Right now, the car has almost stock suspension. Stock torsion bars and stock sway bars. The only modifications are Bilsteins and rear springs have been upgraded to performance springs... I should have bought a race springs instead. As is, there is a huge amount of body roll that I would like to control. I could also use a LSD since on tight corners, with body roll, the inside rear tire likes to spin taking away that very important exit speed.

I felt that a solid chassis is the foundation for a good handling car. I spent a lot of time in designing and developing the roll cage. The car is STIFF... much better than my M3 cage. I feel like all I need is some decent suspension components to make it fun. The balance is good. The body roll... not good.

Last May at AROSC at Buttonwillow, I had my friend (total beginner) drive the car in a time trial (I was co-driving my friend's Caterham in the enduro race). He is now totally hooked and can’t wait till the next track event. I did take out the GTV6 for one session and was pleasantly surprised with the car. The brakes are amazing.

In summary, I would like to stiffen up the suspension without spending a fortune. I'm not trying to compete in SCCA with this car. I just want to participate is various track events and have fun. I would appreciate it if you guys can tell me what your recommendations are and where I can get them.

Thanks for your help everyone.

Colin
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Post by MerrilGordon » Mon Aug 15, 2005 10:59 am

I am not a user yet, but I sure like the RSR system. With that you get coil over shocks at the front with adjustibility for ride height and spring stiffness. Rear springs are adjustable as well, shocks are not.

With stiffer torsion bars you have height adjustability but not any for stiffness unless you change out the whole bar. I think the RSR springs are comon coils with a large availability of stiffness selections.

Of course it goes without saying to get the complete suspension package for ballenced handleing. Note the developer of this suspension runs something like 20 Milano's at the ring for customer rental. Each of these cars use that suspension so I believe it's been very well developed.

My two cents anyway,
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Mats
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Post by Mats » Tue Aug 16, 2005 12:01 am

Don't buy the RSR-system, if you are spending that amount of cash you might as well go the few extra yards and dump the torsion bars all together for a full coil-over setup with custom control arms. That way you can make the front end work like it's supposed to, i.e. roll center height.
The rear will also be greatly enhanced by converting to regular race springs (50mm or 60mm), cheapish and fast/easy to switch out rates. Don't mess with rear geometry (except adding camber and adjusting toe) until you got the front sorted.

Rose joints/ball ends everywhere of course. ;)

Does your cage extend to the shock-mountings? You need that if you add full coil overs, but I don't think I need to tell you that.
A cross brace is nice too.

Any pics of the car?

Oh, yeah, almost forgot; Lighten the h3ll out of it, plastic windows and fibreglass hood/trunklid is a good start. :)
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
-onemanracing.com-
-Strandberg.photography-

GTV 2000 -77 - Died in the fire.
155 V6 Sport -96 - Sold!
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Post by Zamani » Tue Aug 16, 2005 1:05 am

Dude,

He wants to keep the budget under control.

I think 27.3mm torsion bars and a stiffer front sway bar is all he needs.
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Post by Mats » Tue Aug 16, 2005 4:21 am

He also said that he realize that "the suspension needed some serious help" and that he was interested in a RSR coilover kit. :P

FYI, you can make coil-overs yourself from a regular shock with a little thinking and skill with the tools. That will cost far less then the RSR-kit, then ditch the bars and control arms and fabricate a set of new ones to custom specs...
Total cost will be higher then the 27mm bars probably but is includes the new shocks and the possibility to switch to other spring rates and adjust height, that is worth A LOT in my book.

As a special bonus you will shed something like 25 Kg from the front end, the best type of tuning known to man. ;)
Mats Strandberg
-Scuderia Rosso- Now burned to the ground...
-onemanracing.com-
-Strandberg.photography-

GTV 2000 -77 - Died in the fire.
155 V6 Sport -96 - Sold!
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Post by Fortis621 » Tue Aug 16, 2005 9:31 am

Thanks Mats. I'll look into your suggestion. I did see a coilover conversion kit at a local race shop. I think that might give me the best "bang for the buck". The car was already built with coilover option in mind. My shock mounts, both front and back, have been heavily reinforced with the cage extending to the mount at the rear (see attached photo).

If this option becomes too difficult, my next option will be per Zamani's recommendation of using 27.3mm torsion bars with stiffer sway bars. I'll keep you guys posted.

Thanks.

Colin
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Zamani
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Post by Zamani » Tue Aug 16, 2005 12:29 pm

Fortis,

Mats is correct, you can make a grove on the shocks to mount a ring which will be the base for a threaded body. Some just use really strong adhesive.

Send your shocks to a race shop and ask them to convert it to coilovers with 1.75" springs.
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Post by Fortis621 » Tue Aug 16, 2005 1:45 pm

Any recommendations on front and rear spring rates?
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Post by Dennis » Tue Aug 16, 2005 11:20 pm

But is the cage extended to reinforce the front shock towers? This is the most critical as the front flexes a lot under hard cornering. Go really stiff on the front as this will reduce roll.

but with the stock lower a-arms you'll lose a lot of camber when cornering (if they point upwards due to lowering, that is) and the upper a-arm restricts your caster with a coilover. Custom A-arms for coilovers without torsion bars and really ideal geometry however cost 2800 euros here in Holland (but you lose 22 kg!!!). Beautiful pieces of work but sooooooooooo expensive! I'm sticking with stock for now.

I'll ask about spring rates tonight as I'm going to one of the AR challenge racecar builders here in Holland to buy some new goodies :twisted: for my track car.

BTW. How did you fabricate the holes in those gussets? That looks really professional.........
'81 GTV6 3.0 QV
'91 75 TS (track)
'02 BMW 330i Touring
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