Satin. But gloss would work too.

4.2L. 253 ended with HQ.

ADR27 came in in about 9/73 so all engines from then until the end of 1974 were the same. They have the stove pipe setup. PCV air is on the 7 o'clock position with the hose going to the front of the driver side rocker cover. The choke fresh air comes from the top of the carb rather than the air cleaner like a 5.0L.

They are a single port. If you can find a copy of the 1980's Scientific Publications volume 147 HQ-HJ V8 it has a really nice glossy picture of a 1974 HJ 4.2 non-A/C engine bay on the cover.

The PCV at the driver side front is a LH Torana and ADR27A thing I believe. I'll check on the 2 port thermostat housing but I'm almost certain that is an ADR27A thing. The HJ has that single port going to the intake manifold on the driver side and then the heater hose goes to the other intake manifold port on the passenger side, from there to the heater tap. I can get you an image of it if need be.

Put up a photo of the engine. Create an ALBUM, add it in there and create a post adding an album image. The tool for adding an album image to a post is not in QUICK REPLY though, you need to click on POST REPLY right at the top.

That's a HX or later LX engine. It has the first ADR27A type intake on it and I assume it has the matching heads.

Unless it has been chopped and changed it will be QR or HR prefix.

That is a HQ engine. It has been rebuilt using HX heads and intake.

Under that plate is a heat exchanger, just a pipe loop, that exhaust gas runs across between the heads. The carby uses manifold vacuum to suck air through the pipe via the heat exchanger. The pipe out the other side should be connected via rubber hose up to the top of the carby for fresh air. The auto choke operator has a bi-metal spring in it that heats up as the car warms up and then pulls the choke off.

The best thing you can do with that engine if its a good runner is:

But a good used or new Edelbrock Performer 4BBL manifold or a KC one,make sure either is the multifit type that suits all red, blue and black heads.
Get a blue 4.2 Quadrajet (CXL coded) and get it rebuilt.
Get a 4BBL air cleaner.
HEI dizzy and coil, and bridge the ignition switch pink and yellow wires. Goss have aftermarket dizzy and coil really cheap.

You can make it all look original if you like.

Whilst the manifold is off inspect the cam for wear. It's a good time to replace it if it is. Good time to replace the oil pump too if the cam is worn.

Those steel pipes are tapered originally to push into the heat exchanger.

Edited by user Thursday, 14 September 2023 6:40:26 AM(UTC)  | Reason: Not specified

GOSS...? major manufacturers of aftermarket fuel system stuff (fuel pumps, injectors etc)
who have also gone into supply of other engine parts - ignition stuff, engine sensors etc
check out their website -
https://www.goss.com.au/products/

Edited by user Friday, 15 September 2023 9:27:59 AM(UTC)  | Reason: Not specified

Here is a whole HEI kit. Allows you to use the original style HT-HZ leads and not use the big ugly HEI cap. I used this exact stuff on my HJ Premier, with Eagle 7mm leads. Just bought WB/VC plugs and set the gaps to original for those models. Pulled the ignition switch out and shorted the START and RUN terminals together by soldering a strand of copper wire across them.