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Is the Caprice and OCC grille shorter (up and down) than a roadmaster?

I was looking for an OCC front bumper cover like you installed so I could get some airflow to the intercooler and not have it look like a hack job, but comparing the two it looks like the Buick bumper has a recessed area between the headlights whereas the Caprice/OCC is more/less straight across. Also the chrome/black trim differences.

I'm guessing that if I went with an OCC bumper, I'd need an OCC or Caprice grille instead of a Roadmaster? I wonder how that would look?
Yes, you would need the Chevy/Olds grille. I would leave the Buick grille in place because it is unique to the car.

I'm sure you have the skills to come up with something. I know a guy that made a custom bumper that was half Buick, half Mercury Marauder.
 

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To the 94 - Put it on the hoist to give it a good once over from the underside... Lots of rust but all the important things are pretty solid yet.

Pulled all the wheels, adjusted the rear brakes up about a full turn each (didn't seem to change anything?), front brakes/rotors are very new. It needs a tie rod end at least - need to figure out where to stop with it. Tried to fix the underhood light, power to the fuse and out of the fuse block but nothing to the underhood light - Decided to stop digging into this and use my flashlight if I need more light under the hood :)

To the 96 - Put the 12" rear springs in and raised the shocks up 1.5" in an attempt to get the rear end to drop farther so the wheel/tire can be removed. Discovered that the rear end will just hang there bound up on the control arms when it could drop another 2-3 inches. Now I understand why 95wagon (and others) have spherical joints on one end of the control arms. I need to decide what (if anything) to do about this...

Fixed the right front headlight not working (ground wire not connected to ground)

Mounted the last tire to the last rim - tried to balance them and only got one that would balance. First combination had 9lb of road force (very good), 2nd, 3rd and 4th pair had 80+ pounds so that was a few hours spent with no productive outcome. 4 more new tires will be here this week so will try it again this coming weekend. Wheels measure true within a few thousandths of an inch, so thinking it's the tires. Didn't think to take the tire off the good assembly and try it on one of the other rims to confirm until I was driving home.

Got the rear bumper lowered (and body raised) so the tailgate will open. Yet another thing that moved when I tightened the body mounts.

Clearance the exhaust in 3 places that were hitting. Still have a couple more to fix yet. Will address these when the 2nd muffler goes in - Also got the 2nd muffler laid out and plan for install, need another 4" v band clamp but should otherwise be pretty straight forward.

I usually have a bunch of pictures, but really nothing picture worthy this weekend.
 

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Another decent weekend of progress...

Finally have wheels and tires that balance and road force out at reasonable values - what a PITA that was. Final values were 8, 9, 21 and 23 pounds of road force - the two in the 20's I put on the back and the 8 & 9 went on front. For passenger cars, anything under 25 is considered "good" The initial batch was in the 80's!

I was also able to get the 2nd muffler installed - Same size/make/model as the other. Made a large reduction in whistle (but still some) and really brought the cabin noise down a lot. Still a nice rumble when you get after it, but sounds much like a stock truck now. An an extra v-band clamp was added which actually made it easier to adjust the "mid pipe" so it clears the floor and driveshaft. The muffler inlet/outlet is designed to slip over 4" pipe, so had to be expanded a bit to slide over the outside.







In hind sight, I should have carefully tapered the outlet down to fit inside the flange instead of over the top as it made it really tough to weld and not interfere with the band around the outside.

It's cozy, but fits and doesn't hit anything.







Took it out for a nice drive (~50 miles) - really a lot quieter inside with the 2nd muffler, 3 places where the exhaust was hitting fixed, the transmission isn't hitting the floor anymore, etc. It's not as quiet as the new-to-me, all stock 94 RMW, but much closer than it was! Re-learned the transmission which helped the shift flare in some gears, but made them worse in others.

I believe I also found the source of the driveline vibration. Seems the driveshaft shop might have missed a step (or two) when they modified the driveshaft...


The interesting thing is that the transmission end of the driveshaft shouldn't have been touched. All they had to do was shorten it and put the different yolke on the differential end. Maybe it was this messed up from GM? Maybe they shortened it on this end and fubared the fitup? Maybe they didn't balance it at all? Not sure - it's out of the car and headed back there to see if they'll fix it or not. Otherwise will try somewhere else.



Need to drop the back another 1.5" or so, unfortunately the springs are already at zero preload at full extension. I can go with a 14" spring, but only have ~1.5" of adjustment left on the coilover - would have to drop to 200 lb/in to make up the difference which seems too low of a rate. The 300 lb/in springs really helped the rear harshness over bumps compared to the 450's that were in there. There is a slight tire rub on the left front when turning and breaking that will need to be investigated.

Keep plugging away at all these little details...Will hopefully get a nice chunk of time to work on it over thanksgiving and knock out a bunch of things.
 

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Nice driveshaft!!!
Looks like the mess a local shop did to my 5" Silverado shaft the first go around.

If you are concerned with spring clearance at full droop, Google
Coil over tender springs
 

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As good as any

When are Tender Coils ok to use? | AccuTune Off-Road

My personal experience, is only with the flat soft tenders to keep the stack in place at full droop or in pits on air jacks.
Have not worked with the multiple rate setups .
Some of our springs are near 2000 inch pounds so as you can appreciate , VERY short.
 

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Awesome, that makes perfect sense - so the flat spring goes solid in "normal" conditions, but keeps everything together at full extension. That's what I need.

I may have to go back to a 10" spring since I'm guessing this spring stacked solid with the spacer is a couple inches tall at least.

2000 lb/in - that's short torsion bar territory! Guessing there's a high motion ratio there.
 

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Big aero down force
One of the cars ( rarely run anymore) has sliding skirts' that drag on the ground
One, the ratio is backwards in the front . Spring moves more than wheel.
The giant rate springs rarely used, but there
 

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I put a steering box, and drag link in my 92 OCC (White Elephant) on Thursday, and took it to a shop for toe in, and centering the steering wheel (I do not have a toe gauge that works with the stock aluminum OCC wheels, or I would have done it myself.). The manager tried to tell me the right tierod end was bad because it rotated on the ball. It has no play in it, so I told him that I would take it home and swap it. He decided that he could do the toe-in anyway, so I let them do it. The work was good, but expensive. I find the people who see an older person, and try to sell them a line of BS are fun to put in their place.

The Starship is acting up again. Overheating in 5-7 miles. I have replaced everything except the sender, and radiator. The sender seems to be accurate with my laser temp gun. so I am going to get another radiator.
 

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A bunch more little things...

Got the driveshaft back from the driveshaft shop where they fixed the previous imbalance. Car is now much smoother at speed.

Used a air/oil bottle jack and lifted the car by the body at the driveshaft tunnel right where there is a reinforcing rib under the front seats. This made installing the new driveshaft much easier than the 15 minutes of puling/prying that was done to remove it before. Another consequence of tightening the body mounts after everything fits...

Swapped rear springs again and installed the spring tenders mentioned above. A really nice secondary benefit of the spring tenders is that it makes height adjustments much easier when the suspension is in full droop. You're just working against the 5 lb/in spring instead of 300 lb/in. The rear ride height is about where I want it as shown in the picture below, just need to verify suspension travel is there.

Put a bunch of interior trim pieces on, cleaned a lot more stuff out of the inside. Folded the 2nd row seat up for the first time in almost 7 years!

Put a used set of rear glass struts on so now that stays up on it's own now which is nice.

Replaced the 2012 steering wheel clock spring so now the airbag controller is happy and I have cruise control which is nice. Still have an ABS light and codes for implausible front wheel speed. Front wheels read ~45 MPH while the rear reads 60 MPH. I don't know why the software engineers didn't consider the possibility of a continuous power brake or drifting where the front wheels can be 25% slower than the rears :). The solution to this is likely to have front toothed wheels made with 33% more pulses so it matches the rears.

Still have a small coolant leak dripping off the downpipe so should find/fix that someday. Hoping it's something simple, but likely the heater core?

Drove it another ~50 miles, filled it up with fuel and re-weighed it (both before and after). No mileage numbers yet, but will be able to get some next time I drive it since it's now completely full.

The rear bumper/hitch assembly is ~135 pounds and hangs as far back anything can - that and a full tank of fuel give it a pretty decent weight distribution. I've got stock numbers in another post which I'll edit in later.

Stock (with me, 100lb of stuff in the car and 1/2 tank of gas)
  • Front: 2360 = 47.7%
  • Total: 4940
  • Rear: 2560 = 51.8%

With Duramax/6L90E swap (with me, my 7 year old son, 200lb of stuff in the car and 1/4 tank of gas)
  • Front: 3000 = 56%
  • Total: 5360
  • Rear: 2360 = 44% - Missing rear bumper and hitch which is easily 100lb [edit] 135 pounds per the galvanizing place [\edit] at the very back of the car

With ~1/4 tank of fuel (guessing based on 22 gallon capacity and adding 15 gallons below) and the bumper/hitch all together
  • Front = 2940 = 52.3%
  • Total = 5620
  • Rear = 2680 = 47.7%
I added 15.4 gallons of diesel to get it full
  • Front = 2920 = 51%
  • Total = 5720
  • Rear = 2780 = 49%

Transmission still shifts for crap in some gears, others are just fine. Still have an occasional rub on the left front - nothing obvious, but haven't looked too hard.

Did some really bad painting on some light surface rust on the roof. Just something to keep it from getting worse, nothing to be proud of other than it's white like the rest of the car.

There's still a few vibrations to track down - the $8 motor mounts might not have been the best choice :). There's something in the lower oil pan that makes a nice rattle that I should investigate as well.

Still a lot of little things to do, but it does feel nice to be in the part of this project where I can enjoy the last 6.5 years of work :).

 
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