Technical 500 Caddy ?s

I'm playing with the idea of cleaning the cylinders and polishing the crank. Not so much a money thing as just wonder how it might play out. I bought it for the heads and I have some large chamber heads I could put back on it. I plan to make my own crankshaft polisher as it should be very easy to make. Bought a small HF belt sander to rob the motor and pulleys from. Ordered some belts so I can get the length right. Just want to see how much has to come off to make the crank nice. If its too much, I'll get it ground and then polish it again. Supposed to be a 71 engine. Have you used any of the KB or Egge pistons in a build? I saw some KBs on another site and it looked like the ring spacing was real wide between the lands. They reccomend a large ring gap too. What do you use?

Been married to my "dishwasher" for 53 yrs........don't want to screw it up now! She's too good a cook.....

 

Since the weak point on 472/500 Cads is the rocker arm setup, this may be interesting to builders






This shows a simple and less expensive way to upgrade the rocker arms. You still need to get the rocker positioned correctly and be aware that different rockers have different ratios.....so plan accordingly.
Edit: Some good info on geometry.

 

Got a Question about the trans adapter.
Instructions said double up these spacers with the kit.

the hub of the converter is bottoming out on the hub spacer and additional spacing is needed.
Hard to tell in the pic but the hub and spacer are bottomed out with the flywheel.
the adapter plate is 5/16 thick. These are two 1/8th spacers. Logic would say a 5/16 spacer is needed.
But looks like and additional 1/8th would at least be needed.
Any you guys have any issues with these spacers/adapters?

 

Are you trying to space the flexplate back? Won't that cause the starter not to engage properly? I would think you might need a different flexplate. You probably already know that the torq converter has to be the correct depth in the transmission pump, so you might want to check how far the torq converter is from the transmission face when its properly seated. Measure to the lugs on the converter. Then you know that the flexplate has to be there plus the thickness of the adapter plate............and still line up with the starter. I know some of the UNMENTIONABLE Chevy small blocks had bowed flexplates to accomodate torq converters. Mention that because I don't know if they make something like that for the earlier Chevy trans conversions.

 

A 5/16 thick adapter was used to bolt the Chevy Th400 the the Cadillac block.
Flywheel is in the stock location.
The spacers are for the converter.

 

I may have missed it, but why not just use a Cad TH400 transmission?

 

Those are long shaft and slip joint. Im running a th475 with a Doug Nash over drive unit and 2 piece drive shaft.
I like a 2 piece drive shaft with low vehicles. Helps a lot with angles.

 

I'd have figured that you would have just bought the needed gaskets and seals and pulled the guts out of the trans, swapped tail shafts and put it back together and done.
Years ago I helped a buddy swap out tail shafts when the one he bought used had a long tail shaft and his car needed the short one. If memory serves right we pulled the front pump, sat it on something that supported the whole internal drive setup and lifted the case off it, swapped the tail shaft and sat the case back down on it and put it back together.

I had a BOP turbo 400 behind the 350 in my 71 GMC that now has a Cad 500 in it with one of those 5/16 thick adapters a few years ago and never did like the setup with that adapter. It's got the Cad trans with long tailshaft behind the 500 now.

 

Possible. Could do that if I used the 400. I’m running the 475 due to the weight.
The bus weighs around 6700 pounds empty.
Plans are for a cool camper. Add all the weight for an interior plus gear plus towing something.
I helped a guy with a 472 in a 80s gm truck.
Used the adapter without the converter spacer. This particular adapter was 1/4 inch thick. Used 3 simple spacers for the flywheel and no issues. Just wondering if anyone else had interference issues with the converter spacer.

 

Mine didn't come with a converter spacer and I think that was part of the problem with it. The converter may not have been in the pump as far as it should have been.

It seems like it would be better to take a hole saw and cut three spacers out of 5/16 plate and drill them to 3/8 and match the thickness of the plate and maybe have a bit more contact surface to mate the converter and the flex plate.

 

That’s kinda the plan.
Thought about making the spacer the same size of the face of the lugs on the converter. (Hope that makes sense). Then possibly weld the spacers to the converter.
The 475 converter uses 6 bolts.

 

I see what you are talking about with the spacers now. I think you would be better with some aluminum spacers and keeping them reasonably small so you don't add any imbalance to the conversion. If you need some made, I can make you some once you know the size.

 

Well the worlds longest engine build continues.
Fired it up, took forever to get it primed up.
Removed the pump and filled it with oil, that took care of it.
We played with the timing and had it running great. Stuck a muffler on it and heard an internal tapping. Not good.
Turns out we had a rod bolt just barely tapping the oil pan.
Removed the pan and massaged the area with a shaping mallet.
Got around 3/16 clearance without the gasket now.

Seems the 500 stroke didn’t like the 425 pan.

 

When I put the 368ci Eldo/Seville pan on mine I had to massage that area a bit as well. The front part of those pans is pretty shallow.

Glad it was a fairly simple fix

Bobby

 

And still in the run stand

 

Some info on using a manual trans behind a Cadillac:

https://www.fourwheeler.com/how-to/...qSflTz_AcTOjtRGaOPFaXrnPVOxGC-TcISlq6MqJzouE4

 

Anthony, do you know what years/models had rear sump oil pans on the 368/425s?

 

I always thought it was just Eldorado's. They fit all the engines in this family.

 

Google "Bad Seed Chevette"; enough said. I am Butch/56sedandelivery.

 

The car we robbed parts from was a 77 Deville
RWD 425
It’s technically a mid sump.
I think the front wheel drive cars are the rear sump pans

 

It's the front wheel drive cars that have the rear sump oil pans. The Eldorados and Sevilles. The 368ci in the Eldos and Sevilles ran from 1980-1984 (I think). If you're scrounging the wrecking yards you will also want to grab the oil pick up screen and the dipstick and dipstick tube (note: the dipstick tube gets installed in the other hole in the block)

 

rebuilt the q-jet last week.
Fired it up with the corrected oil pan.
I think we’re good now

 

Cold start up this morning.
The fast idle cam isn’t doing it job.
But not to bad for a 30 degree startup

 

Idles like a supercharged top fueler

 

Sorta does.
Needs idled up a tad and the fast idle cam figured out.
We will get the exhaust manifolds looking better once we see if they work in the chassis.
I’m hoping I have room for headers but will break the engine in with the manifolds. I’ve already learned that lesson.

 

When I was in HS a friend installed a newly built 327 complete with a brand new cam and headers in his Nomad. He was all excited about the initial start and cam break in. He was planning on doing it with open headers. Luckily his dad stepped in and told him that the noise from open headers at 2,000 RPM for 20 minutes would prevent him from hearing any start up problems (as well as pissing off the neighbors). Looking back its funny how smart our fathers could be when we were in HS.

 

Yep. We didn’t notice the rod tapping the oil pan until we installed a muffler.