What spark plug for a '65 327ci, 350 hp?

[Stuart F.]

Re: What spark plug for a '65 327ci, 350 hp?

Thanks Joe and Tim. I kinda figured those N plugs were big block, more likely (in my case) a W engine; 348 or 409.

I'm still playing with the 3461S carb and have some issues remaining to work out. Its' WOT is great, but it still wants to lope at low speeds and gears. I just sent my top plate from my 3720SA parts carb out for reconditioning and will use that on the 3461S. The restorer of one on the 3461S left the brass vent tubes in place during bead blasting and the cut off tips are eroded. Also, the guy never did send me the proper fresh air tube (aluminum instead of brass). I won't do any plug change/inspection until I'm satisfied with the carb.

I filled up with 90 octane non-ethanol today so we'll see if there is any improvement. They used to handle 91 octane, but it was recently discontinued.

Stu Fox

[Joe L.]

Re: What spark plug for a '65 327ci, 350 hp?

Thanks Joe and Tim. I kinda figured those N plugs were big block, more likely (in my case) a W engine; 348 or 409.

I'm still playing with the 3461S carb and have some issues remaining to work out. Its' WOT is great, but it still wants to lope at low speeds and gears. I just sent my top plate from my 3720SA parts carb out for reconditioning and will use that on the 3461S. The restorer of one on the 3461S left the brass vent tubes in place during bead blasting and the cut off tips are eroded. Also, the guy never did send me the proper fresh air tube (aluminum instead of brass). I won't do any plug change/inspection until I'm satisfied with the carb.

I filled up with 90 octane non-ethanol today so we'll see if there is any improvement. They used to handle 91 octane, but it was recently discontinued.

Stu Fox

Stu-----


The "W" engines (348, 409 for those not familiar with the term) ARE big blocks. However, they are Mark I big blocks and not the Mark IV big blocks used in 1965-74 Corvettes as well as 1965-75 passenger cars and 1965-91 trucks.

[Edward L.]

Re: What spark plug for a '65 327ci, 350 hp?

Wow, so much info, this is really helpful. When I got the car it had AC 43R in it. The plugs were fouled black, I'm going to try the Denso W14-U plugs. From what I've read here these may be the best choice. Any other options? I'm all ears.
Thanks ED

[Duke W.]

Re: What spark plug for a '65 327ci, 350 hp?

Yeah, as was mentioned before, the NGK B4.

How many choices would you like? You can always grab some spark plug catalogs and look at the interchange data for the AC 45 like I did or look up spark plug interchange data on the Web.

Then we can have a runoff between choices.

Why do some of you guys take something easy and try to make it into something like solving the nuclear arms proliferation problem?

Long time owners have found that AC heat range "5" is the best choice for normal driving in vintage Corvettes, but non-resistor plugs for vintage engines are no longer offered in the Delco brand and cross referencing to other brands is not rocket science.

I'm in a bad mood because the Huskies are getting pounded by the Indians.

Duke

[Edward L.]

Re: What spark plug for a '65 327ci, 350 hp?

Don't take a game so personal and I'm not trying to make this harder than it has to be, just simply asking for advice from fellow members. Hope the Huskies win.

[Stuart F.]

Re: What spark plug for a '65 327ci, 350 hp?

Duke;

Being as you are a Wisconsin Alum too, you really did have a bad day yesterday! The Badgers went down to Spartens.

Stu Fox

[Michael W.]

Re: What spark plug for a '65 327ci, 350 hp?

I'm in a bad mood because the Huskies are getting pounded by the Indians.

Duke

And for those tuning in from foreign lands, I believe Duke is referring to a football game and not some weird program on the Nature or History channels.

[Michael H.]

Re: What spark plug for a '65 327ci, 350 hp?

And for those tuning in from foreign lands, I believe Duke is referring to a football game and not some weird program on the Nature or History channels.

..........

[Duke W.]

Re: What spark plug for a '65 327ci, 350 hp?

Duke;

Being as you are a Wisconsin Alum too, you really did have a bad day yesterday! The Badgers went down to Spartens.

Stu Fox

Ya had to rub it in, didn't ya. But you forgot to mention that my Bruins got mauled by the Wildcats, nothwithstanding the streaker and bench-clearing fight just before half time. Oh, well, at least that was entertaining.

Meanwhile, those evil cross town Trojans beat the Irish.

Now, on to next weekend's schedule and probably more oil questions.

Duke