I found the bill and checked. The carb was "cleaned, bead blasted, and dipped" by Bowen Automotive (Carbueration) in Bristol, Pa. for $100
It's not paint and definately will not rub off. In the old days IIRC these were chromate dipped, but I've no idea what they use now-days.

Just checked.
They use an ultrasonic cleaner, and dichromate dip. Looks just like new!
https://www.bowencarburetor.com/

 

Cracked the diff open and drained it. No obvious issues (whew). Except for 3 very leaky seals.
Used engine stand to hold it as suggested by GTR1999
No obvious posi unit cracks, loose pinion shafts, etc.
Factory 336 gears look good.
Draining the oil was not even messy using this method!

 

I’m sure Gary suggested it, but while you have it apart, are you planning to install a drain plug?

 

Oh yes! Thanks for reminding me. I cannot imagine trying to change the oil in this without one!

 

Differential housing case all done. Deburred & rounded all rough edges and casting seams inside and out. Derusting was a challenge because I did not want to sand-blast or Evaporust dip. Spent hours with a Dremel tool .

This black oxide layer (Iron II Oxide) was very tough. There was a lot of rust underneath it.


Used Eastwood's tough Chassis Primer


Eastwood Cast Iron Grey Topcoat.

 

Wow I haven't updated this in a while.
Mostly spent a lot of time working on the diff, blue-printing it, and toughening it up for my big block:
https://www.corvetteforum.com/forums...post1603774911
With GTRs help, it's all done now:



It's still the original diff and gears. I needed a new posi case.
To toughen it I used:
ARP ring gear bolts
main cap socket bolts
deburred & polished posi case
cryo treated posi case
deburred ring gear and spiders
tuned posi aka "Tom's diffs"
steel posi discs
blue-printed clearances

I spent a total of $818 in parts and at least 100 hrs of my own labor::
Posi Carrier $300
Ring & Pinion 0
Spiders 0
HD Posi Solid Steel Clutches $190
Timken Bearing& Seal Kit $185
Cryo $100
ARP RG Bolts $35
Cap Screws $8


When I coated the inside of the frame I discovered no less than 12 hidden internal frame "bulkheads" in the main frame that reinforce it's structure. I documented their location here:


Today I loaded the diff crossmember into the frame.
The Van Steel delrin kit was pressed in on my shop press
The crossmember itself also needed a little persuading to load onto the "sombreros" on the frame
If anyone remembers I had a lot of trouble removing this crossmember, one sombrero got damaged, and the welding/dent repair must not have been perfect, but it went together, with a little help:

 

ingenious press...most would have gone to the 10 lb tool.....the HAMMER!!!!!BWAHAHAHAHA.....oh forgive me, my inner Bubba took over for a second. I cant wait to see the rest of it. YOu have any motorr pics yet

 

I tried the 10lb hammer trick. It didn't work! LOL
Turns out the someberos are tapered a little bit and the delrin is .030" too small for a tight fit, it has to be pressed or "squeezed" on.
Since I greased it up, and with the taper fit, it just kept popping/sliding off! PITA! Floor jack would not work since the frame is too light. So I got "creative" with wood so as not to scratch the powder-coat.

The engine build-up goes back a year or so and was done by my buddy Jeff before he passed. He was one of the the best engine builders in Philly:
If you missed it here is the link:
https://www.corvetteforum.com/forums...ls6-build.html

 

Well I was making some progress on assembling the frame...


Then I decided I should double check my newly straightened frame and see if my alignment is any better than it used to be.
Here's how bad my alignment used to be when the frame was bent. (Supposedly the car went in a ditch years ago.)

So that was one of the original clues that all was not right with my frame.
The right side should not have 1/2" of shims while the left side has none right?

So I did a lot of comparing my frame measurements to the frame charts.
Almost all of it checks out good. A lot of things are like 1/8" of an inch off, but that is as good as it got in the 70s.
My frame shop did a great job of straightening my frame. It was 1" off before.
But now that I have hung suspension on it there is one more thing I found that probably got welded on improperly decades ago.

This right lower a-arm mounting bracket is the only one of the 4 arm mounting points that is not exactly 8" from the centerline of the chassis.

Used a laser setup on the chassis centerline. That bad mount pulls the ball joint 1/2" further back than the other side giving the right side 3 degrees negative caster, when I want 4-5 positive!

I see no alternative but to cut that mount off and weld a new one back on 3/8" to the right.
You can tell how bad the welds are, on that mount, those are not factory welds, that thing has been re-welded.

These lower a arm mounting bracket measurements are not even in the frame dimension charts. I took a survey a while back and came up with about 16" ctr-ctr, and parallel.

406 or 408 mm seems to be the common measurement. That is exactly 16" and parallel, (+/- 1/16")

 

Well I have had a hard time making much progress on this lately.

Life got in the way.... medical problems slowed me down, and a few other things.
I started swapping out the brand new rubber front suspension bushings out for Ridetech Delrin bushings and that turned into a nusiance.

Well that is still half done, and I still need to have my frame "adjusted" one more time to correct the alignment numbers that I did not like.
One step forward...two steps back. It'll get there. Eventually.

The good news is I have fully recovered from the stroke I had, and that little experience has convinced me to retire from teaching this spring!
That will give me a lot more time to work on this project.

So ten weeks and counting! Woo-Hoo......

 

So sorry to hear about your health issues and great news on the stroke recovery. Best wishes on the retirement!

 

Really enjoyed reading through this thread! Hope you have a swift recovery, and congrats on retirement!

 

I’ve got you beat!
I’m retiring in three weeks after thirty years in law enforcement and code enforcement.
Enjoy every day, stay healthy, and let’s see who finishes their project first.

 

Well It's been a while, but I have made three big decisions lately. I had to give all three of these a lot of serious thought.

First big decision was my cam.
After much discussion, my new Bullet cam has arrived. I will re-cam my never installed 454 primarily to enable me to run smaller valve springs on my L88 aluminum heads. I was too concerned with their reliability / longevity given the awful casting porosity issues they seem to have. Jebby even said they look like coral inside! LOL
https://www.corvetteforum.com/forums...-al-heads.html

Here are the new cam specs; not too much different from the old solid roller one or an OEM LS6 solid cam.

Once you factor in how much duration you lose with valve lash, this one is just a touch larger @ .050" and it allows me to drop the spring pressures way down from solid roller level to hydraulic roller level. 240/550# down to 160/420#. The new one is a milder hydraulic roller profile vs my original solid roller, but I'll be using my Morel Ultra Pro Solid Roller Lifters with pin oiling. This will not be a show car or a garage queen, I plan to put 20k miles on this thing in road trips during retirement. Lower spring pressure just seemed to make sense, since I can make it run basically the same.

The Second big decision I made was taking a big leap and start cutting on my freshly powder coated frame so I could get the alignment settings I want.

--------------------------------------------------------New Frame brackets from Vette Products of Michigan

I'll be replacing the right lower a-arm mounting bracket, while shifting the rear of it outward 2/8" to move the ball joint on that side forward 3/8" to correct my wheelbase and caster problem.

This was likely welded improperly at the factory in 1972. But the car was also wrecked. The car always had an odd shim stack for alignment. The wheelbase was 3/8" shorter on that side. And I could not get over 3 degrees positive caster on that side vs 8 degrees on the other, when I did my on jack-stand alignment. I also need to go back to the frame shop later on and have them rotate the right frame rail counter clock-wise 3/8" as well. My A-arm tower spread is 26-6/8" and not the 26-3/8" it is supposed to be. Too wide, definately not sagged! Anyway the combination should fix the alignment issues.

Third big decision I made lately was to delay retirement by one more year. My wife was too uncomfortable with the this-year plan. Oh well, school is off for the summer in only 4 weeks!

 

The year will go quickly.
I extended my original retirement date for two years due to the cost of healthcare, but the time flew by.
I’ve been on vacation time for the past six weeks and I’ll exhaust all my vacation time on June 01.
My first official day retired is June 02.

I also kept my camshaft to a somewhat mild grind to be about to keep the motor more street friendly, and add some longevity into the valve train.
Its a hydraulic roller which comes on at 2000 rpm and pulls to 6000 rpm.
I think you made a wise choice.

 

Ok I have been trying to get this old mis-placed lower A-Arm bracket off.
I got two surprises.
One I found a fatigue stress crack under the bracket immediately to the inside of one of the welds. Just one more thing to fix. But know I understand why these things have "torn-off" the frame a few times and why the reinforcement brackets are handy. I guess I'll be adding those as well.

Here is the new bracket next to the fatigue crack next to the old weld.

Next thing I found is grinding is very slow work. Aren't I lucky that I had the welding reinforced before I decided to take this bracket off? LOL Now I have 12 welds to grind off instead of the original six. Yay! So fun!

 

Thanks,
Now I something else to look for during my frame disassembly.

 

I finally got my pro welder acquaintance to stop by to fix my frame bracket, he even brought a buddy. These two guys really know how to weld, just this week they were working in a Nuclear Power plant! Their welds are as smooth as spread butter. I think my lower a-arm will be just fine!


They were literally laughing at how bad the 50 year old factory welds were. Said they would kick a guy that did welds like that back to journeyman status.

They weld 3 foot diameter 2300psi stainless steel steam pipes in electric power plants, 5/8" thick. Their welds frequently get X-Rayed and re-done if their is any porosity (air-pockets). Jim did the welds above left-handed, with 2 broken ribs and a ruptured right shoulder due to a motorcycle accident. Still awfully nice welds, and they were the roughest ones in the bunch. Interesting characters!

My lower brackets are parallel now, as they should be. 16.0" center to center. One end was off almost 3/8" before.

 

Looks like your moving forward.
I'll be watching your progress.
Cheers.

 

Some more slow progress.
Engine went back to the shop for some lighter valve springs. Working with Jeff's sons now after he passed.

Weighed it while I was there, just for fun:


543# with 1 gal oil, engine cradle, and chain.

Pulled and checked a valve-spring. Yep they were solid roller springs, 250# seat, 550# open. I am going to soften them for reliability. That means a cam change too. Going for something closer to 160/400# and a gentler ramped Hydraulic Roller profile.

While I was pulling the roller rockers, I documented how my Poly-Loks that fit under the stock short valve covers. I had a couple of questions lately.


The poly-loks are barely any higher than the stainless rockers.


You can see how my machinist buddy cut them down. 0.80" high. But I believe the Crower short poly-loks are the same height. He just found it quicker to pop them on the lathe rather than wait for the mail.

When we change the springs, we will also change the Titanium retainers. I heard the flat spring dampner will chew into them. OK for a drag motor, but not for my street motor.


We found some pretty "healthy" pushrods inside. Jeff built this strong to last.


Also I completely forgot about the extra head bolt these 074 heads have, but there they are in the bottom of the runner. They go in upside down with a hex wrench.



This is one other mild mod we are going to make. We'll add a valley cover to keep the oil off the intake. The factory one did not fit with the roller lifters and the flat 569 intake.


Now here was a cool custom made tool. Hydraulic powered balancer puller. This balancer came off in like 3 seconds!!! No sweat. You can make stuff like this when you have a full machine shop, and you need it when you do thousands of engines. It began life as a 3 jaw puller from Harbor Freight.