Datsun Roadster Forum-311s.org

I have a question. On my 67 1/2 1600 R head there seems to some wholes on the exhaust port wholes, to where the header goes. They are close to where the screws go where the bolts that hold the head to the block go. I dont seem to know what exactly goes there, i have another head and it does not have those wholes. Im guessing it might be one of those smog heads or something? If you guys know what goes there please let me know.

Thanks

If the holes go down into the head at about a 45 degree angle, and actually are drilled into the exhaust port, then yes, that is a smog head.

So if thats the deal, does anyone have whatever goes there that will sell to me or something? Or is sealing those holes an option?

Joaquin

The smog holes can just be plugged. Go to your local hardware store (not home depot, try Battels in Whittier) and get 14mm 1.5 thread bolts. They will fit in the holes. Those are air injection holes that were necessary for the smog devices. I also have the hole device if you're interested in putting the stock smog back on (better off.) You'll also have to plug the 2 holes on top of the intake manifold. Those are actually 1/4 pipe thread. I got some nice allen hex bolts that fit in mine and are level with the top of the manifold.

Ron
whittier,ca
69 1600

DELETED

What was the smog thing for anyways? What was it for? I just want that thing to be normal, and not have any noise problems like Mark said.

I think ill head to the hardware store and just plugg those holes.

Thanks for the help.

Joaquin

Your car should not have had the smog equipment since that was not adopted until 1968. I can tell you how to cheap out on the plugging and NOT get the chirping. Get some allen head cap screws that fit down in the holes. The length should be enough to go into the port. Put pipe plugs on top of them. They will stop the noise.

I did this on a 2000. I did not keep the exact specs though. It was not hard to figure out though.

I just used standard metric bolts and I get no chirping sound. They go into the head about 3/4 of an inch then stop. Where did you get the hex nuts? I couldn't find those, but I'd prefer the flat look.

Ron

so.... my head may not be original? Im sure that the block is because the #s match all around. I have a non smog head, but the head was overheated, and is not straight and may need a cut. So i guess im going to go with the bolts to seal em.

Thanks

Joaquin

You DO have a smog head. I can make you a set of plugs pretty cheap and quick. They will not chirp as I did the same thing for my engine. IM me tomorrow night and I'll get back to you.

Will

OK. I got some pics of a Non-Smog head that I have. But the deal on this one is that the water holes, or whatever seem to not be right. And the head also is not straight (possibly overheated). What do you guys think i should do?





Joaquin

Is it an aluminum head, or a cast iron one. An R16 is a pushrod engine, so you will have a set of holes that goe straight up into the top for the push rods. The holes that will tell you if its a smog head drop down into the exhaust ports not into the combustion chamber area. The will be threaded as well.

Will

The round holes in the bottom of the pictures that are directly under the valves are where the pushrods live. They're machined. The weird shaped holes are the ones for the cooling jacket, and are just cast when the head is made, then the head is surfaced. If it appears that one (or more) is too close to the combustion chamber, I imagine it could be welded and then opened back up, as long as the hole area is the same as stock, but this sounds like a last-resort option to me.

FWIW, in my opinion, the head doesn't look too bad. But what do I know?

So uh? Do you guys think it will still work with no problems like that (after the cut that is)? I was thinking maybe getting that head on my block instead of the smog? What would be better???

Thanks Joaquin

Get it running with what is on there now. You can make it "correct" later. Just get it driving first....