Took the white 70 for some exercise. Developed an exhaust leak (loud). Found the cause....she’s missing a bolt (plug) from her early exhaust manifold. Anyone know the thread size of this item, or better jet do they have one they could spare? 

Thanks

Guy

Is that not the narrow band O2 sensor location from a ZX manifold?  Never seen an early manifold with a need for either an EGR fitting or O2 sensor that would explain that hole. Unless it was a later user added "feature"

Anyway if its O2 bung thread, its M18x 1.5. 

https://www.google.com/search?q=280zx+exhaust+manifold&rlz=1C9BKJA_enCA668CA668&oq=280zx+exhaust+manifold&aqs=chrome..69i57j0l3.6099j1j7&hl=en-US&sourceid=chrome-mobile&ie=UTF-8#imgrc=wbMsjPBtTsxSnM:

Edited March 17, 20196 yr by zKars

Right you are Jim. It’s not an early manifold, it’s a manifold from a ZX with no exhaust tubes......W48. I tried 3/8 and 1/2 inch plugs.....one too small and one too large. I just want to plug it. I’ll order an M18x1.5 plug. Thanks so much for your help.....I am always impressed with your knowledge of Z cars.

Regards

Guy

3 minutes ago, Diseazd said:

Right you are Jim. It’s not an early manifold, it’s a manifold from a ZX with no exhaust tubes......W48. I tried 3/8 and 1/2 inch plugs.....one too small and one too large. I just want to plug it. I’ll order an M18x1.5 plug. Thanks so much for your help.....I am always impressed with your knowledge of Z cars.

Regards

Guy

They will probably have one at your local big box parts store too.

Glad to help.  Speed shops that sell weld in O2 bungs will also have plugs. Some of the bungs I've bought actually came with the plug.

Edited March 18, 20196 yr by zKars

1 hour ago, zKars said:

Glad to help.  Speed shops that sell weld in O2 bungs will also have plugs. Some of the bungs I've bought actually came with the plug.

Great....I just ordered 2 bungs with the M18x1.5 plugs. One for each of the two Stroker Motors (I’ll have them welded in the Dow pipes). Curious as to how the A/F ratio is with the SU’s. Have you ever checked your Stroker with the SU’s? If so, what were your numbers?

I had a great experience with my SU's with the stroker motor. Nearly equal performance in the low/mid range as the Mikuni 44's I had previously, excellent mileage, easy starting etc. AFR's with N47 needles on cruise at 15'ish, 12-13 at WOT

I believe a Spark Plug is M18 x 1.5 if stuck on an island.

 

The Professor.

2 hours ago, zKars said:

I had a great experience with my SU's with the stroker motor. Nearly equal performance in the low/mid range as the Mikuni 44's I had previously, excellent mileage, easy starting etc. AFR's with N47 needles on cruise at 15'ish, 12-13 at WOT

Perfect.....Yes I love the way the strokers pull with the SU’s and their simplicity. Just didn’t know if they were lean at WOT.

Thanks

1 hour ago, 240260280 said:

I believe a Spark Plug is M18 x 1.5 if stuck on an island.

 

The Professor.

You think If I screwed in an NGK I could get it to fire on 7 Blue?

Afterburner ?

My Dad told me when he was younger somehow or another they put plugs in the exhaust and made fireballs come out the pipes. My Dad bullshits me a lot though. Pretty funny  now that he's 80 and nuttier than a squirrel's turd.