jimbosprint 1972 C20 - the good, the bad, and the ugly

[BB72CHEVKT]

I have the same motor in my burb and do not run the heat shields and the wires have
25k miles on them and they are perfectly fine.

[knomadd]

I don't know for certain, so maybe it's not correct, but it looks like you have the boss for the hole to be drilled in the block. Couldn't the machine shop drill and tap the hole for you, if they don't have the heat shields that can work with the combo as-is?

[no1udknow]

Originally Posted by Xeen

Honestly the metallurgy in the new crate motor is so much better than the old 60's-70's small blocks it's not even funny, you have the better deal with what you have you just need to figure out a solution and trust me it's out there.
You will burn up your spark plug wires very quickly unless you shield and route them properly then you will definitely be unhappy, don't give up so easily.
The local machine shop will know in 2 seconds what heat shields you need with that block/exhaust manifold combination so load up the engine and take it down there, they will probably even have them in stock and sell them to you.

Burn up the wires??? Jimbo, I can't remember an engine that I have had that ever burnt up wires without heat shields. Yes, most of them had headers, but even ones with the OG mani's and no heat shield never burnt up wires. But as far as the heat sbield mount goes, are you afraid to drill and tap it yourself? You may need a special tap to work with the hardness of that block, but you can take a dial caliper and measure the depth of the holes on the old one, and then mark it out on your drill bit so you dont go too deep, then just use a corded variable speed drill, go slow, and use lots of cutting oil. You could do it man, I have faith. Then when you are running the tap, you go 3/4 turn forward, then 1/4 back to remove debris, and keep spraying the cutting oil. Youll be done in no time.

[Xeen]

I'm not talking about burning up the wires with radiating heat I'm talking about the wires touching the exhaust manifolds and burning up, it has happened to me before.
If the wires are properly separated and routed you won't have that problem though.

[boostedc10]

Jimbo worse case if you don't want to drill and tap it, cut the tab off at the bottom weld a small piece to it to make the 90 and use the hole next to it. No1 is right though, if you take your time you can drill and tap it with very little risk.

[jimbosprint]

What heat shields?

Engine is in the truck!

[Saclandman]

Originally Posted by jimbosprint

What heat shields?

Engine is in the truck!

Lookin' good in there. Light the fires!

[boostedc10]

Originally Posted by jimbosprint

What heat shields?

Engine is in the truck!

Lol, problem solved!

[jimbosprint]

Here it was mocked up on the engine stand.

[no1udknow]

Just run straight lead plug wires an you will be fine, if you run the 90° ones, they might get melted.

[jimbosprint]

I'm gonna try to run em down the back and under the manifolds like stock.

[jimbosprint]

So (I hope) everything is hooked up except the transmission kickdown cable. Somehow the Edelbrock "universal" SBC throttle bracket I got is not so universal. I have the stock throttle bracket hooked up temporarily so it will work mostly, but it won't go all the way wide open throttle.

Just need to fill with fluids, prime the oil system, and install the distributor.

Then... first fire!

[Saclandman]

Lookin' sharp in there, Jimbo. Good work.

[Xeen]

Nice work, you are almost there.
Edelbrock probably makes a bracket that will work properly with the cable throttle that you have, now you have me curious, I'm gonna look into it.

Edit:
Ok I found some throttle brackets on Ebay using the search term "edelbrock throttle bracket GM 1972 truck" part # 8031 so give that a shot.
The only other thing I found is a GM Transmission Cable Adapter but that is for the 700R4 and similar transmissions.
Edelbrock has the worst part descriptions ever for accessories!

[jimbosprint]

So I'm pretty sure the radiator leaks. I don't know if it was leaking before. It was full when I bought it. It sat in my yard for most of this time that it was out of the truck, but I did take it up to the transmission shop to have the lines cleaned out.

[jimbosprint]

Strange. I put a pan under the leak and it appears to have stopped.

[jimbosprint]

Turned the key, got it to run smooth and the timing set pretty quick. Noticed quite a bit of smoke and shut it off. Would anyone with experience mind if I called to talk about it? PM me your number. Thank you!

[swamp rat]

Rising off the outside of the engine? That could be the exhaust manifold dressing curing.

Out the exhaust? burning the assembly oil off the rings would be my first guess.

You didn't mention the color of the smoke, white would be water, blue is oil and black is too much gas (to rich)

[jimbosprint]

Super short YouTube video

It's breezy out so I noticed it by the engine, and my first reaction was to look for oil leaking near the exhaust. But it was definitely coming out from the tailpipe (and leaky old exhaust). Smoke smelled lightly of oil burning and was white-ish or light blue-ish, but blew away quick due to the wind. Oil pressure gauge showed near "H" while running.

Before startup I ran an oil priming tool for 3-4 minutes while turning it over manually to put oil throughout the engine. Pressure gauge showed oil pressure while priming. I used Red Line engine break-in additive with zinc in the the oil and topped off the level before startup.

--

Started it up a second time and it didn't smoke right away, but did smoke like the video above within a couple minutes. Smoke increased when engine was revved up (didn't go above 1500).

--

I just don't know what to expect so I shut it off out of caution, and I don't remember this much smoke at first firing when I put a rebuilt 350 into my Nova 15 years ago. Do I need to rev it up higher to seat the rings? Should I do the 20 minute break in at 2000rpm and just let it billow out?

[jimbosprint]

Bump.

New somewhat longer video: http://youtu.be/mCncKo0Ch20

[Xeen]

Jim maybe the guys in the engine & drivetrain section can provide some answers.

[jimbosprint]

Just needed to break it in, or it could have been burning off the old exhuast pipes. Smoke stopped after about 10 minutes. I test-drove it around a little (my first time driving it) with a ear to ear grin.

[Saclandman]

Sweet! Drive it on down to Sac, we'll take it for a spin.

[Xeen]

Originally Posted by jimbosprint

Just needed to break it in, or it could have been burning off the old exhuast pipes. Smoke stopped after about 10 minutes. I test-drove it around a little (my first time driving it) with a ear to ear grin.

HAH I knew it!
I'm glad to hear it Jim, congrats!

[jimbosprint]

Photo gallery update (285 photos).