[Scarebird]

Originally Posted by eaglesan13

What about non-a/c cars. The battery, alternator, power steering, and starter are all on the drivers side...

One thing I always thought Chevy did better, putting all that heavy stuff on the passenger side.

[njsteve]

Maybe the bodies get torque-twisted over the years? I know when I had Mopars, several of them (440 and Hemi powered Cudas and Chargers) had cracks in the rear, passenger side floor where the twist caused a split in the same place in each car.

Is your spare tire out of the trunk?

[vitamin c]

njsteve,
After recently doing the same rebuild to my 74 SD, I'm faced with the same problem of the left front being considerably higher, like 3/4 inch. After the front and rear springs were replaced I noticed the lean from behind the car and have traced it to the driver front spring. I used replacements #cs5402 from Classic and noticed right away they don't have the same tapered (flat) top coils as the originals. They look identical top to bottom, but they paint a white mark on one end and call that the "top" of the spring, and install "up". What I'm noticing is the driver spring is not sitting vertical in the frame spring pocket. The passenger side installed perfect and sits centered and vertical. Saturday I'm pulling the left front back apart to find the problem. My guess is that the sprint "top" is not siting in the correct groove in the frame. I used a bore scope to see up into the frame and see the spring doesn't look right. I'm assuming that the round replacement coils don't sit correct in the frame as original.

[njsteve]

That is one of the problems with the generic one application-fits-all springs from places like Classic Industries. While not ground to a taper, the company that built my springs bends the lowest section of the coil so that it is touching the next coil at it's tip. The top is regular coil like the original spring. This way the bottom can sit into the pocket in the lower control arm. The upper locating area in the subframe has a circular cage that the spring locates around. I don't think the upper can be out of its spot without major problems in getting the spring to fit into the area. It's kind of a go or no-go situation at the top. Yuo may have the spring siting half on that circular cage, causing the upset height.

[vitamin c]

I agree with the go, no-go installation , but something isn't right as far as I can tell. without the "flat" upper coil, its causing coil bind of sorts. I can see the spring is in its correct location, but I cant tell until I remove it to confirm. I may go through a lot of work to find there is nothing I can do, but the lean is driving me nuts

[njsteve]

Is the bottom coil end sitting in the "pocket" in the control arm? The easy way to check is to insert a drill bit into one of those two small holes. If the drill bit doesn't immediately touch the bottom coil through that hole (and instead has a 1/2" movement upward) then the coil is not in the pocket and needs to be rotated counter clockwise and reset.

[vitamin c]

yes, the bottom sits nicely in the pocket of the control arm. I cleaned and painted mine identical to yours, so no crud or rust causing an issue. The bore scope camera shows the top coil not sitting real level, but its very hard to see what the actual issue is (if there even is one). ill report back after this weekend and let you know what I found.

[njsteve]

I brought the car in for an alignment today and was pleasantly surprised. As assembled, the caster and camber were perfectly in spec and only the toe was out of spec. It was toed in, probably due to the wacky driver's side lower ball joint/spindle wallowing situation. I brought my bag-O-shims with me but the car didn't need a single shim, whatsoever.

She tracks straight and true and the steering wheel is straight. YAY!

Now, on to the rear suspension. The front end is completely silent. But I can hear squeeks from the worn front leaf spring bushings and the squishy Midas shock absorbers and worn sway bar bushings. I had already replaced the rear shackle bushings last year when I replaced the gas tank. The new KYG as shocks arrived yesterday and now I am waiting for the new sway bar bushings that Summit is drop shipping from Prothane. This car has the small 9/16" sway bar which was a little tricky to find bushings for.

https://www.summitracing.com/parts/PTP-7-1116-BL

[vitamin c]

Pulled the driver front spring again, didn't see any problems during disassembly. I decided to grind the ends of the top and bottom coils to stop any contact of the coil ends. after reassembly its better, but still has a lean. I'm going to run it and see if it settles, I'm not pulling it out again. Those coil springs are like a hand grenade!

LF=29 7/8 RF=29 1/8
LR=30 1/4 RR=29 3/4

[njsteve]

I went and did the drill bit in the two inspection holes in the lower control arm. My springs are both located in the correct pocket where the spring end is supposed to sit.

Maybe when I refurbish the rear springs i will swap them side to side to see if it offsets back to normal. It could be that 80,000 miles and 42 years of torque tended to wear a bit more on the passenger side leaf spring. Anyone who has ever seen a pickup truck with right side of the bed noticeable lower than the left, knows what I mean.

[njsteve]

We took Gramma's car out today. It was around 20 degrees and sunny out. The boy needed some driving time for his learners permit so we drove the car around the neighborhood roads. He was plodding along at around 20 mph and eventually felt confortable enough to hit a rollicking 30 mph by the end of the half hour of driving. It was a most entertaining time. His sister's first driving time was in this car, too. Nothing like creating new automotive memories in his Great Grandmother's ancient chariot that was built a quarter century before he was born.

When we got home I decided to swap out the too hot of a heat range plugs for a set of ACDelco R44TSX's. I had NGK UR45s in there but the flame pattern seems a bit close to the base ring.

[Formulabruce]

44 is a great heat range considering that the ethanol makes engines run hotter than the would back in '75

[njsteve]

We shall see when his next driving practice day comes. :-)

[njsteve]

I pulled the spare out of the trunk today and noticed that it is the original spare tire from 1975. Its a B.F. Goodrich Lifesaver Whitewall F78x15 manufactured the 23rd week of 1975. Cool!

[njsteve]

BTW, I guess there must be some type of built-in macho blessing on Firebird drivers from the Patron Saint of Trans Ams: Burt Reynolds.

I looked at my 16 year old son today and he now has the faint beginnings of a mustache that he did not have prior to test driving the car yesterday.

Too cool for school!

[njsteve]

It was around 45 degrees today so I pulled the rear out to start the process of swapping the 3.42 gears for 3.08s. I have a set of GM 3.08s that a PY forum member sent me to trade for the GM 3.42 set currently in the car.

Here's the result after four hours of work.

[OVERULD]

Very cool Steve! We'll soon be swapping the 3.73s in my car for a set of 3.08 gears, so this will be fun and educational for me to follow.

BJ

[njsteve]

I dropped the rear end off today, along with the vintage set of gears. The guys there rolled their eyes a bit that I am re-using original GM gears (it's a race/chassis shop) and indicated that they don't give any gaurantee about how noisy they may be. I told them that my decision was based on prior experience with the quality of modern aftermarket gears and I can live with whatever they sound like.

Plus I dont think they give any kind of gaurantee about how noisy a brand new set might be either. :-)

[77 Canamman]

I have used new "quality" R&P sets, and they have been noisy. I would have done the exact thing you are doing.

[unruhjonny]

I have heard time and again about the quality of currently available r&p sets;
I have also come to understand that used gears are perfectly fine if they are not worn...
and if the r&p are set to match the way they were previously run, you should again be fine...

Curious to hear about the end result, and the thoughts/opinions of the shops tech(s).