Dan I'm looking for the part numbers for the cap rotor and the spark plugs not the hei stuff when you upgrade from points to electronic ignitionyou said there was a certain cap A Certain rotor and NGK plugs

Plugs depend on what year head you're running. If you have a '74 or older head (with the spark plug tubes) shoot me a PM; I've got a new set of the premium plugs I'm not going to use and I'd rather have the shelf space so I'll make you a good deal on 'em. If you've got a '75-up head with no spark plug tubes, use NGK UR5GP spark plugs.

Cap: United CC611X

Rotor: Echlin MO-3000.

Plug wires: Magnecor or Aurora.

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Too many people who were born on third base actually believe they've hit a triple.

I have a 66 drool tube head

OK, I'll send you a PM about the spark plugs.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

NGK GR4 for compression < 10:1, otherwise use GR45 or GR5.

Lou

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Home of Slant6-powered fun machines since 1988

I respectfully disagree with Lou; if you're buying NGK plugs off the shelf, use ZFR5N. A "4" plug (in NGK's numbering system) is unnecessarily hot and will limit the amount of ignition advance you can run before you get pinging. A "5" plug is more appropriate, which is probably why that's the original-spec heat range. And the ZFR5N plug design, with its projected extended electrodes, gives a benefit over the standard electrodes on the GR5.

But check your Inbox; I've sent you a PM.

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Too many people who were born on third base actually believe they've hit a triple.

The theory is the extended tip plugs are better. However, the extended tip plugs are highly suspected to have destroyed a couple of high performance turbo Slant 6 motors (hot spot detonation) and caused additional detonation/pinging on others relative to standard plugs, so I do not use them. I have always had good luck with NGK GRs and non-extended plugs. On a 9.5:1 or lower comp, or stock motor, I would use extended tips, sure.

Personally, I think you would be hard pressed to measure any performance increase (mileage or power) with any different brand or style of plugs. You would at least have to do very careful testing. Detonation/pinging difference, you can see a difference. I use the NGKs partly because I think their manufacturing is probably more reliable, although I think I have Autolite 63s (made in Mexico or US) in the turbo Dart.

Probably GR5 is better than GR4 since new ignition systems generate more spark energy than points and a stock coil and you don't need the higher heat range anyway.

FYI, the GR4 is indeed the original heat range (RN13YC or RN14YC). GR5 crosses to something like a 9-11 heat range in an old Champion plug. The current cross references I could find online seem to have the GR4 as being a lower effective heat range than a 5 in an extended tip plug.

I would be curious to know what others have observed when switching to extended tip plugs, in terms of driveability or performance. Please describe your testing and car/engine setup.

Lou

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Home of Slant6-powered fun machines since 1988

Just my 1/2 cent worth. This pertains to a nitroused slant. I have never used the long nose plugs. I have actually had a problem with autolite plugs, the last few years. Ceramic blowing out of the shell. Plus even running the correct heat range for the application, the ground electrode running too hot causing preignition. Went to NGK B7ES or B9ES (depending on the amount of nitrous) and that cured the problem. The NGK has a shorter ground electrode. This is for the "Drool Tube" head. When using the "Peanut" plug head I use the NGK R5673-9 Which also has a short ground strap.
Reminder, this is a over 10-1CR nitroused engine, not a street engine.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Well, um, yeah, they are nowhere near an appropriate spark plug for that kind of engine for reasons having nothing to do with the projected electrodes: their heat range is way too hot for a high-perf turbo motor. That's not the kind being discussed in this thread.
Never been my experience.
NGK 4 is a Champion 14-15.
NGK 5 is a Champion 13-14.
NGK 6 is a Champion 11-12.

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Too many people who were born on third base actually believe they've hit a triple.

Since I gather you have never run a serious performance Slant 6, your observations make sense, so no problem there.

I wonder why the parts stores and lookup books starting 25 yrs ago (and still?) have told me that GR4 crosses over to a RN13YC or RN14YC?

Can you point me to a current and reliable crossover reference, Dan?

Thanks,

Lou

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Home of Slant6-powered fun machines since 1988

I have this one bookmarked from NGK.com's learning center....It's current as of 4 years ago..but was instrumental in picking the correct plugs for my 11:1+ SCR engine builds....

https://www.ngk.com/learning-center/art ... sion-chart

Hopefully Dan has a newer one he could reference, I'd be appreciated.
There used to be one that also had Delco plugs on the chart...I had to go that direction as the delco R-45 plug for the peanut head was a perfect heat range falling right in between the UR5 and 4.

There was a series of posts back in 2002(-ish) about the projected tip plugs at a more modern Dodge Truck board (late model Dodge Trucks) that had discussed the difference in moving the kernel in the combustion chamber and one of their guys did some tests with the "regular plug vs. the projected tip" and determined that the kernel placement was more centered in the combustion chamber, which also had the effect on combustion of adding in about 5 more degrees of timing... if the boosted vehicle is already dialed in on it's max allowable timing adding 5 more degrees would put it into detonation..(unless other measures were taken to help the situation...back off timing, richen up the fuel mix, etc...)
I think I'd be worried more about the projected tip coming apart/getting burned under the exposed ravages of the boosted engine anyway... I know that a few racers have gone to the BPR style of NGK to suit their needs on the very high compression and other builds in our area.

That's just my 2 cents...

-D.Idiot

Correct, I don't race, so I'm not qualified to (and therefore don't) give advice specific to race motors.

My heat range statement comes from the application and heat range detail sections of an NGK master catalogue I no longer have (gave away most of my cattledogs last time I moved -- only kept the ones with info not available online), combined with experience of how the various plugs do in terms of staying clean, aggravating or staving-off ping, showing evidence of running too cold or too hot or just right, etc.

Here's why I do it that way instead of just putting one maker's spark plug number into the cross reference finder and using the result to generalize about heat ranges:

Here's NGK's cross for Champion RN14YC. It shows 4s and 5s. Here's Champion's cross for NGK GR5. It shows RN14YC.

Here's NGK's cross for Champion RN12YC. It shows 4s and 5s. Here's Champion's cross for NGK BPR4ES. It shows RN14YC, too.

Here's NGK's cross for Champion RN11YC. It shows 4s and 5s. Here's Champion's cross for NGK BPR5ES. It shows nothing.

Here's NGK's cross for Champion RV15YC. It shows a 4. Here's Champion's cross for UR4. It shows RV15YC.

So that's one cross out of this collection of spot-checks that gives exactly the same result in both directions. All the others are either different or give several different cross options. And where are the Champion 13s? The 12s? Cross-reference charts can guide us to a plug that will probably fit and probably work, but they can't tell us more detail than that.

It might be nice if spark plug heat ranges and their designations were standardized industry-wide, across all brands like wheel bearing sizes, grease seal sizes, etc, but we don't live in that world.

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Too many people who were born on third base actually believe they've hit a triple.

OK, that is what I was seeing for the different charts online. Yes, unfortunate that heat ranges are not standardized. It seems likely that plugs are assigned a heat range based on factors that are not necessarily just detonation propensity.

Thanks for the input, DI. The idea of the timing advance difference is new to me, but makes some sense.

Lou

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Home of Slant6-powered fun machines since 1988

I don't know for sure, but it wouldn't surprise me to learn that each spark plug company uses its own method to determine heat range ratings. There's an SAE Recommended Practice, but RPs aren't anything like mandatory, they just basically describe industry practices. And this one says right in the header The spark plug preignition ratings obtained with the equipment and procedure specified herein are useful for comparative purposes and are not to be considered as absolute values since different numerical values may be obtained in different laboratories.
Interesting. Anyone fixin' to CC a drool tube head in the near future? I'd be curious to learn the difference made by regular vs. projected-nose spark plugs. On the face of it, it seems to me the projected-nose plug might tend to increase CR slightly, just by occupying more space in the combustion chamber. Maybe enough to equate to a 5° timing bump…?
Agreed. I just can't see using projected-nose plugs in a forced-induction or high-compression motor; they strike me as the wrong tool (plug) for that job. For many years, the go-to plugs for various extreme motors have been the opposite: various recessed-electrode designs.

Back to the world of stock(ish) street motors, and leaving aside any compression ratio change: the projected-nose plug moves the spark out where the fuel/air mix is more consistent, away from the quenchout zone created by the cylinder head metal. That means more reliably complete combustion -- it's why the projected-nose plugs were developed when tightening emissions regs made it extra-crucial that every cylinder lights all the way off every time, and used in motors like the AMC 258 and Chrysler's '81-'83 EFI 318. Chrysler continued using projected-nose plugs like this (not always the exact same plug) in motors like the Jeep 4.0, the 3.2 and 3.5 V6s, etc. IME, using them in a \6 makes an appreciable improvement in how the engine runs: starting's a little easier, idle's a little smoother, driveability's a little better. Not an O-my-gawd, rock-my-world transformation, but a small improvement for no extra money or effort. I'll take it!

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一期一会
Too many people who were born on third base actually believe they've hit a triple.