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BigSwede said:
Wasn't he asking about shocks for track racing? There is (IMHO) no way you can seriously drive a 105 car on the track without some really stiff springs, you can't use std springs, they are utterly worthless at the track and hence you need dampers to match the springs.
On the front only ... but yes your point that shocks relate to spring stiffness is what I was trying to say.

Thus to set up a track car you have to control suspension movement FIRST ... this dictates your spring stiffness. Then you need a shock matched to the spring rate.

What is currently happening (especially by these modified road car BS ... fueled by the stupid street racing films) is that owners are just chucking really stiff shocks in these cars and making them handle very, very poorly (especially traction wise) ... but ofcourse they bounce around and hit the bumps hard, thus the novice owners are thinking 'cool this car is like a race car'.

Anybody that has driven a well setup race car on good roads knows they are not uncomfortable at all ... at the speeds they were designed for, quite the opposite.

Remember it is all about keeping the wheels on the ground ... and thus if you are going to play with the suspension settings, you need to do the whole hog ... otherwise leave alone, because Alfa Romeo knew a heck of a lot more than most of us.

Pete
 

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I agree, almost. ;)

A good race setup isn't road worthy in most cases since road quality in most cases falls outside the designspec. of the racing suspension i.e. you will bounce all over the place and have poor grip because the road is too uneven.
And I do believe you need to stiffen the rear alot too, just stiffen the front more. :)
 

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BigSwede said:
I agree, almost. ;)

A good race setup isn't road worthy in most cases since road quality in most cases falls outside the designspec. of the racing suspension i.e. you will bounce all over the place and have poor grip because the road is too uneven.
Yes emphasis on Good roads. My last club car only weighed 512 kg's and thus was actually quite good on a normal road ... er, the street where I lived (never really drove it on the road ... just impromptual road tests :D :D ).

And I do believe you need to stiffen the rear alot too, just stiffen the front more. :)
I believe that unless you run a sliding block, watts linkage or panhard rod to lower the rear roll centre to have to run the 105 series really fncken hard in the front and relatively soft in the rear ... now I guess this could still be harder than stock, like you say.

Plus I also imagine that not many track 105 series Alfas with the original rear axle location.

Pete
ps: Race tracks in New Zealand are not billard smooth ... so I guess we may run a little softer than you guys :p
 

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Discussion Starter #24
Shocks and Relationships

Hello,

I wanted to thank everyone for the comments with regard to shock stiffness on my '73 GTV track car. I wanted to apologize for not providing more detailed information about my suspension mods before I asked the question. SORRY>

Here are the mods

Panhard rod, camber -1.5 to - 2.0, GTA Wheels 14 x 6.5, TOYO PROXES RA1 205/55-14, poly bushings all around, larger rear bar(IAP), stock front bar, IAP RED SPRINGS (CUT...stiffer...but not race??), KONI classics-FRONT: full stiff, REAR: almost full stiffness

ENGINE

Rebuilt by Mike Besic (3,000 miles or so), 11 mm cams, port polish (milld), Wes Ingram stage 2 pump, 10:1 HC pistons, GTA exhaust, Shankle headers, OMP Seats, 5-point harness


The car feels nice......pretty guick and sticky with those tires and panhard rod (I'm a huge fan of the panhard rod). It's still too soft up front with the classics set at full stiffness.

It's almost a great car...but not yet. Please forward your suggestions. Thanks again

michael :p
 

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mister said:
It's still too soft up front with the classics set at full stiffness.
Okay so what you are actually saying is you think the front SPRINGS are too soft. Fair enough. To confirm (this is a trick that was told to me many years ago) put a cable tie around both front shock shafts and do a few testing laps.

If the cable ties have been pushed right to the end of the shock shaft then your front suspension is indeed too soft and the car is settling on to the bump stops (which is bad as all of a sudden the front has no suspension movement and an equivalent huge spring rate).

Thus you must change your front springs until you get off the bump stops ... then you can adjust your shocks to match. Usually if you increase front stiffness you need a bit more negative camber too ... but I always used to believe in less is best when it came to negative camber. Some just chuck on way to much and then never use the full tyre width ... your really need to make this adjustable so testing will show you what is right.

It's almost a great car...but not yet. Please forward your suggestions. Thanks again
Sounds like a great car to me :) .

Pete
 

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I missed this thread the first time, since I was out on the Salt...

George, how heavy are your cars, typically?

On my heavy GTV, the red ones work well with W&D set up, but may have thought to go with the yellows when I build a "real" car. Sounds like I may not have to...

Eric
 

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I use 2-way adjustable shocks on my car. This makes the car VERY STIFF, however it also makes the car VERY FAST, and conversely VERY SKIDDISH. It took me a long time to get used to these shocks however, once i did they gave me 3 seconds at Willow Springs over the Koni Reds. These shocks are expensive but a must for any serious race effort. From 1:37's to 1:33.171 (personal best).

Its in the adjustments where the real gains can be made. For instance, at Road America i gained 4 seconds from adjusting the shocks, from a 2:45 to a 2:40(lost my ignition system, only could go to 6000 instead of 7000).

Thanks,
Richard
 

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RtbRacer said:
Its in the adjustments where the real gains can be made.
Thanks,
Richard
Could not agree more. That is why REAL race cars change springs, shocks, etc. for every track.

I believe a car should be set up as soft as possible ... but always hard enough to keep off the bump stops. If you run a car too hard the car will be skitish and have poor traction over bumps ...

Some people just think stiff/hard when they think race track ... and it sure feels fast but they are having to work their butt off to keep it on the track.

Adjustability is the key ... as is testing (to find the right settings).
Pete
 

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For what it's worth...

I met Carroll Smith, (Tune to Win, etc), at some seminars we both worked at, and I retained him to advise/help with GTV handling problems.

His advice was to start with the front, and install progressively stiffer springs untill the front "skates" in the most important corner onto the straights, then go backwards on the spring rate by 10 %. Then go and do the same in the rear. Then work on shock absorber adjustments.

This is a simplication of the things he outlines in his "Tune to" books.

Buy them!! Read them!!

Incidently, he said shock absorbers are one of the very last things to change. He broke a corner down into five parts, and said the shocks are a factor in the second and fourth sections of a corner only, IE: during transitioning. Think about it.

Hope this helps, George Willet
 

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The best setup I have used is 1600# front springs, 185# rear, 1 1/8" heim jointed front bar, panhard rear (no sway bar) and carrera shocks. You can modify the rear trailing arm spring perches to accept 5 x 13 circle track springs and make your spring choices much greater and tons cheaper.
 
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