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Discussion Starter #1
I suspect that no matter what I do to my Alfetta's front suspension, that as long as it retains the torsion bars, I'll never be happy with how it (doesn't) handles (bangs over) sharp bumps - which includes the intrusive Bots Dots.

I'll add that I first need to carefully examine my suspension mounts, etc, just to make sure there aren't any mechanical/physical problems causing the loud bangs.

I've run across these coil-overs made by ridetech. They are not inexpensive, but there sure are both a lot of options for stroke (2.9" - 6.9"), and for the springs themselves can be had in 7", 8", 10", 12" lengths, and from 200lb lbs/in to 800 lbs/in - not to mention the lower spring mount is adjustable over a very wide range.

Modifications would need to be made to the mounting points - see photos I pulled off a much earlier ABB thread. Since these ridetech coil-overs were designed for older American cars - as opposed for racing only (or darn rough riding street cars) I would imagine that both a less harsh over sharp bumps but retaining much of the good handling qualities ride could be found - unless small diameter (these are 2.5" ID) springs can never be made to be both compliant yet handle well.

Assuming these coil-overs might be the ticket, how to calculate what would be needed? All I can come up with is there is a 6 1/8" difference from full length to compressed length (I assume this is the stroke?) of a front Koni gas shock. There is a 6.3" stroke available for these shock absorbers.

The LA area has lots of freeways which are basically smooth, but 'undulate' to some degree - meaning pea poor leveling out of the concrete. My Alfetta has no poroblem with this and would hate to soften up the front so much it rides like a 50's US car and bounces up and down as it goes along.

Would I be wrong in guessing that the front of an Alfetta GT with A/C (battery in the rear) and all liquids is about 1500 lbs - making it 750 per side?

For $700 I'd prefer not to experimint too much, though since the springs are only $75 each, I wouldn't mind getting a couple of sets to start with.

Any calculations and comments are welcomed.

Biba
 

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try the qa1 site,, i got my shocks there for my spider, rears are coil over,, the front are also coil overs, but useing the stock spring area not enough room for the coil overs in the front.. the rear easy 12" 200 inch/lbs rear springs( my fronts are 1150 inch/lbsmy qa1's $145 ish each.. adjustable at summit raceing..2.5 springs are 35.00 each
 

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Discussion Starter #3
bianchi1, are you saying you've not installed the front coil-overs yet? Or have and modified the upper suspension arm's opening? Also, the eye (believe that's the correct term) upper mounting needs to be resolved. Are the QA1's installed on an Alfetta GT, or?

I'm completely in the dark as to how to proceed. I don't even know how to correctly measure the length of a shock absorber. I would imagine the coil over ones would be from the uncompressed center of the eye to the center of the eye. On the Alfetta front shock the eye has the rod going through it with a post mounting at the top. Does one include the rubber mounting ring or not? And this is only Coil-Over 1A.

I'm surprised you have 200 inch pounds at the rear and 1,150 in the front. Big difference for a car (I'm assuming Alfetta) with close to 50/50 weight distribution.

Did the folks at Summit Racing help on what shock and springs would work best for your application? I found only one front coil over on their website which is close to the Alfetta's 18" uncompressed shock absorber and it is $300.

What I like about the ridetech coil overs is that they're not meant for racing and they list all of the sizes and spring weights in one place.

Thanks for your input,

Biba
 

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sorry, my car is a spider...my mistake,, but the qa1's are very nice and cheap, and you can re-build them at home if you want, parts are very nice:)
 

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I'm surprised you have 200 inch pounds at the rear and 1,150 in the front. Big difference for a car (I'm assuming Alfetta) with close to 50/50 weight distribution.
The massive variation has very little to do with the weight distribution of the car and everything to do with the motion ratio of the front suspension design of the 105 style chassis.

I'm currently trying to figure out how to pick shock/damper specs for a given spring rate because I want to apply off the shelf Bilstein digressive valve dampers to my 75 (Milano to you lot :p).
http://www.pmzracingproducts.com/6_7_8_bilstein_36mm_shocks.html: While a 36mm shock sounds very skinny, that is the piston diameter. The outside tube is the same diameter as a Koni Yellow. The wonderful thing about these Bilsteins, apart from the very reasonable cost and digressive valves, is that they accommodated the 1.875 threaded spring seats that I adapted to my Koni Yellows.
 

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I don't get it. The torsion bar front end, stock, is relatively soft, and has lots of travel. Any banging is going to be via shocks and not the torsion bars, so you need to fix whatever it is (shocks, mounting bushes whatever) that makes it bang. If coilovers fix it it will only be because you end up with a matched shock and spring rate (if you do) and/or have addressed any mount issues (as you say - you need to check that first). You can fix those issues without going to coilovers. The transaxle alfas are great cars for rough roads - there is something wrong with your car's suspension setup (not its design) if it isn't coping.
 

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Biba,
I used to have an Alfetta and Darryl is right -- lots of travel and no banging. Unless you want something really stiff for racing, why don't you think about some stiffer stock torison bars from a GTV/6?
Mike R
 

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The RS racing coilovers are used in conjunction with the torsion bar, you would have to do a heap of reinforcing to convert to a full coilover setup which would be extremly expensive.
My alfetta has a standard setup lowered very slightly with koni shocks and it handles great.
I had a knock in the front on rough roads but it was caused by worn inner tie rod ends and bushes in the steering rack, caused a horrible noise that echoed through the car.
Reconditioned the rack and now its quiet

Cheers
Fetta GTV
 

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The RS racing coilovers are used in conjunction with the torsion bar, you would have to do a heap of reinforcing to convert to a full coilover setup which would be extremly expensive.
My alfetta has a standard setup lowered very slightly with koni shocks and it handles great.
I had a knock in the front on rough roads but it was caused by worn inner tie rod ends and bushes in the steering rack, caused a horrible noise that echoed through the car.
Reconditioned the rack and now its quiet

Cheers
Fetta GTV
Agreed - the first place to check for banging noises on the front of a 116 series car is the steering rack. The end bushes all go eventually, the rack itself wears where it rests on the little pad under the pinion, the rubber wrapped around the passenger side mount comes out....the list goes on.

Another common source of knocking noises is the inner bushes on the lower arm. Really if the steering and suspension are in good condition the front end should be pretty quiet. I've driven many Alfetta's over the years including on some pretty rough roads at speed and the standard setup is really very good in those conditions. You drive the thing on the throttle anyway!
 

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Discussion Starter #12
The steering rack was replaced with one from a low mileage '79 Alfetta GT. It was considerably 'tighter' than the ('75) rack I took off.

The photos above that I pulled from a (I believe) '06 ABB thread show that there is no torsion bar installed. Plus I like the idea of the two springs, the lighter one would dampen initial bumps, with the heavier spring doing the, umm, heavy work. I'm sure it was set-up this way for racing - but I need to go back and try to find that thread, to see if that was the case.

My gut feeling is that torsion bars, by design, are not going to dampen well on initial 'impacts' - whereas a coil spring, especially one with both tightly and loosely wound coils will handle hard bumps much easier. If I could get a set like the one above and both the shock absorber and dual springs come in various ft.lbs., could then find someone who can calculate what is needed, then I'd be more than happy spending a day driving the car, then adjusting a bit untill I'm a happy camper. Quite possibly how I'd set it up might be quite different than how the rest of you would adjust it.

I do accept that since my front has been lowered, the shock absorbers will then be more compressed and most likely less complient than if I'd left it in the US setting - with tons of space betwee the top of the tire and fender edge. It measures 26 1/8" from floor to center edge.

Biba
 

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The tender spring in your photo above is normally collapsed. It merely serves to keep the main spring from coming loose when the suspension is at full droop.

You can stack two springs of different rates which yields the equivalant of a softer linear spring. For example, stacking a 100# spring and a 200# spring would result in a 67# equivalant spring (1/100+1/200=1/67). The resulting spring becomes progressive (i.e. gets stiffer) when the coils in the softer spring start to close up.

Transient handling is mostly about the shocks. Steady state handling is about the springs & sway bars. It is not clear to me which is your primary concern.

Mike R
 

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26 1/8" doesn't sound particularly low. I have an old shell downstairs on standard suspension that has no engine in it, no bonnet and most of the trim stripped - I just measured that and the equivalent measurement is 27 1/2".
 

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I do accept that since my front has been lowered, the shock absorbers will then be more compressed and most likely less complient than if I'd left it in the US setting - with tons of space betwee the top of the tire and fender edge.
Shock absorbers are a force vs velocity device. The faster you make them move, the more they resist that movement (until the shock starts to cavitate and aerate the oil or they have an internal bypass valve that 'blows off' the internal pressure). So lowering the front has changed very little if any of the shocks behavior.

Combining spring rates is also a less than ideal arrangement. Proper damping for a single rate spring is enough of a job to get decent. Trying to dampen a very much varying rate spring set up would be very difficult and time consuming and that's assuming you have a damper that can be configured for such a task. Penske's, anyone? :cool:

Initial suspension movement from a change of direction or braking is low speed damping (up to about 3"/second). Damper movements above 3"/sec to 12-13"/sec would represent decent size road bumps and constitute high speed damping. Above that is off road territory and not the kind of thing you should be doing with your Alfa.
 

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Discussion Starter #16
I don't believe that I've mentioned it here, but I've always felt that I have the front lowered at least reasonably close to where they were designed for - meaning that outside of the US, your Alfetta originally came with the correct height. US Alfetta's were lifted up to pass stupid headlamp height requirements. The same set of requirements that also said that any other type of headlight other than sealed beams were illegal.

To answer Mike R, I'm totally interested in transient handling - or more correctly, feeling. I have no argument whatsoever how my Alfetta handles, but to sum up what I'm looking for is: I want to be totally unaware of what my front suspension is doing (like my rear suspension). I want it to not act like it simply doesn't know what to do when it is introduced to a raised area in the road - let alone a whole series of very uneven surfaces - as opposed to undulating roads which it is fine with.

Mike R, should you ever be heading west on the 10 and are in the one of the farther right lanes and you've just passed over the 605, let me know how your car handles. This is not a typical stretch of concrete, but my Alfetta GT really sounds as if it goes on for much longer, it will disintegrate. It is only about a 1,000 feet but I dread every time I have to cross this no man's land. I'll add that I come from the 605 and have to cross two lanes just to get into the far right lane (you have to be there), so it's not that I purposely drive over this stretch of freeway. Though it is my ultimate suspension testing area.

I completely rebuilt my entire front and rear suspensions - including tie rod ends (using rubber everything) 8K miles ago. I actually have a Shankle sway bar in the rear and it doesn't feel harsh at all.

I restore Alfa's, almost entirely Spiders,for a living and never have this problem with their suspensions - but of course they have (real) springs, not torsion bars.

I have a partially dismantled 2.5 Riley I bought more years ago than all of you combined and it handled great. It has torsion bars front, and leaves rear. You can adjust the front height by turning a bolt on either side of the torsion bars. It also has a 119" wheel base which helps a great deal - but still, this is 1950 design/engineering.

Biba
 

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Re ride height - too true. Even what we got here was too high so what the US got was just, well, daft!
 

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My Alfetta died a sudden and violent death on the Harbor Freeway some years ago. :(

Suggest you replace any worn components that go clunk and bump. Then, seek the advice of other Alfetta owners as to what shocks best meet your needs. Modern digressive shocks would be ideal, but I doubt if any shocks listed for a 35 year old car meet that criteria. Maybe another Alfetta owner has blazed that trail.

Mike R
 

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I had to break the heart of a customer once (a very young 'dude') telling him that "no, I wouldnt lower his Alfetta any more no matter how cool he would think it looked, and if I did it would only result in a cracked windscreen, AGAIN, or his untimley death on a quiet back road somewhere. Yes, the car ended up backwards in a gaurdrail for other reasons and he wasn't hurt, much.
 

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I had to break the heart of a customer once (a very young 'dude') telling him that "no, I wouldnt lower his Alfetta any more no matter how cool he would think it looked, and if I did it would only result in a cracked windscreen, AGAIN, or his untimley death on a quiet back road somewhere. Yes, the car ended up backwards in a gaurdrail for other reasons and he wasn't hurt, much.
Wow, he must have done something really stupid to achieve that. Especially when lowered Alfetta front equals less front grip (understeer).
 
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