New Rear A Arm bushings = re-alignment?

What makes you think it's in alignment now?

I would. Anytime you touch the suspension, you should get an alignment. The car will handle better and the tire wear will be less.

 

Replacing worn bushings should, in principle, return the car to stock settings but I too would suggest that you have alignment checked after.

 

Not only should you have it aligned, but first you should have it corner weighted and ride height adjusted. Only then will the alignment put the tires at the proper relationship with the chassis.

 

For those of us that are not that familiar with the alignment procedures would you provide a brief explanation of ride height adjusting and corner weighing.

 

Ride height adjustment: You adjust the spring perches so that the distance to the flat and level surface with tires at normal pressures to be within factory spec of the ride height of that car.

Corner weight adjustment: You adjust the spring perches so that both front and both rear tires carry approximately the same weights, AND such that 50% of the total weight is carried by the sum of the left front and right rear.

These two adjustments (obviously) interact and have a tiny interaction with the camber and toe. So the whole shebang is long drawn out procedure.

When done correctly it gives the car a totally planted feel. To curve to the left/right under acceleration or brakes, takes steering input the same in both directions; in plain language, the car just feel right.

 

Unfortunately, the older models, like 308QV, don't have adjustable spring perches so not possible unless the stock shocks/springs have been replaced/upgraded/modified.

 

Yeah, the procedure on the Hunter alignment machines is quite different than your average car out there. For starters, you look up your car and behold, most of the Ferrari's including older ones are in the system. It shows you photographs of the suspension and where to adjust. It recommends putting 200 pounds of weight inside before aligning. (The ideal is if you the driver were sitting in the car during the process.)

Once we do my suspension work (all new bushings and rebuild rack) we will balance the tires, phase match the rims with the tires and do a fresh alignment. I look forward to this process at the same time as dreading it.

Definitely should get a 4 point alignment after any suspension work for sure. The rear wheels have an effect on the front wheels so it is best to do all 4 wheels at once.

Good luck
David Govett

 

I was under the assumption that this stuff was done to race cars to setup for constant left turns around tracks by biasing these across the front/rear and left/right. Anyway would the ride height spec be in the OM or WM? Would you set it up for one or two people in the car? How about gas weight? Seems like a lot of variables. How would the aftermarket 16" affect the setup?

 

I'd say be all means wait until you've done all work before you have the alignment checked and set. There can be a fair bit of work involved and there's little point in doing it now only to do it all over again in a few months with limited mileage in between.

 

I have read that shimming of the springs can do the adjustment but the tradeoff is that you are no longer in the center of the springs operating range and could, in theory, bottom out the springs.

 

Alfa's, Ferrari's, most decent cars specify placing weights in the seating areas to mimic people on board. Tech Bulletin SB 00-3 states that static load is 2 passengers, full fuel load, spare tire and tool kit.
The 308GT4 WSM has drawings of the front and rear suspension giving ride height etc. They specify the length of the shock extension, which should be the same (I think) regardless of rim size. (Rim size matched with correct tire profile doesn't actually change the rolling radius that much).
I don't have a 308QV WSM so can't vouch for its content.

The most common reason for ride height problems on 308's would be tired springs. When I replaced mine the ride height went back to normal and the handling improved noticeably. And it needed a full alignment of course.

For the carbed cars you can retrieve the 1980 Service Bulletins from my web site.

Gerrit
ex owner of 11966
http://dino308gt4.com

 

I called Hunter headquarters and they sent me to the regional sales manager who referred me to the best local shop with the Hunter system and a good tech to do my suspension. The folks at Hunter are great. Call them for the best referral in your area.

http://www.hunter.com/ then click on local representatives. These guys know who is doing what and who knows what they are doing.

 

The easiest way is to find out what the length of the shock extension at rest is supposed to be from a WSM. Or the height of frame from ground although that is more sensitive to rim/tire ratios. Springs sag over time, mine were original from 1976. The more expensive way is to remove them and use a spring tester to very length and the amount of pressure required to compress them a specific amount. At that point you might as well replace them regardless of result There are aftermarket ones available at reasonable cost.

Gerrit